District heating
Encyclopedia
Space heating
A space heater is a self-contained device for heating an enclosed area. Space heating is generally employed to warm a small space, and is usually held in contrast with central heating, which warms many connected spaces at once...
and water heating
Water heating
Water heating is a thermodynamic process using an energy source to heat water above its initial temperature. Typical domestic uses of hot water are for cooking, cleaning, bathing, and space heating...
. The heat is often obtained from a cogeneration
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....
plant burning fossil fuels but increasingly biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
, although heat-only boiler station
Heat-only boiler station
A heat-only boiler station generates thermal energy in the form of hot water for use in district heating applications. Unlike combined heat and power installations which produce thermal energy as a by-product of electricity generation, heat-only boiler stations are dedicated to generating heat.The...
s, geothermal heating
Geothermal heating
Geothermal heating is the direct use of geothermal energy for heating applications. Humans have taken advantage of geothermal heat this way since the Paleolithic era. Approximately seventy countries made direct use of a total of 270 PJ of geothermal heating in 2004...
and central solar heating
Central solar heating
Central solar heating is the provision of central heating and hot water from solar energy by a system in which the water is heated centrally by arrays of solar thermal collectors and distributed through district heating pipe networks .For block systems, the solar collectors are...
are also used, as well as nuclear power
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...
. District heating plants can provide higher efficiencies and better pollution control than localized boilers. According to some research, District Heating with Combined Heat and Power (CHPDH) is the cheapest method of cutting carbon, and has one of the lowest carbon footprints of all fossil generation plants.
Heat generation
The core element of a district heating system is as a minimum a heat-only boiler stationHeat-only boiler station
A heat-only boiler station generates thermal energy in the form of hot water for use in district heating applications. Unlike combined heat and power installations which produce thermal energy as a by-product of electricity generation, heat-only boiler stations are dedicated to generating heat.The...
. Additionally a cogeneration
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....
plant (also called combined heat and power
Combined Heat and Power
Combined Heat and Power may refer to:* Cogeneration* Combined Heat and Power Solar...
, CHP) is often added in parallel with the boilers. Both have in common that they are typically based on combustion of primary energy carriers. The difference between the two systems is that, in a cogeneration plant, heat and electricity are generated simultaneously, whereas in heat-only boiler stations - as the name suggests - only heat is generated.
In the case of a fossil fueled cogeneration plant, the heat output is typically sized to meet half of the peak heat load but over the year will provide 90% of the heat supplied. The boiler capacity will be able to meet the entire heat demand unaided and can cover for breakdowns in the cogeneration plant. It is not economic to size the cogeneration plant alone to be able to meet the full heat load.
The combination of cogeneration and district heating is very energy efficient
Efficient energy use
Efficient energy use, sometimes simply called energy efficiency, is the goal of efforts to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve and maintain a comfortable temperature...
. A simple thermal power station
Thermal power station
A thermal power station is a power plant in which the prime mover is steam driven. Water is heated, turns into steam and spins a steam turbine which drives an electrical generator. After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was heated; this...
can be 20-35% efficient, whereas a more advanced facility with the ability to recover waste heat can reach total energy efficiency of nearly 80%.
Other heat sources for district heating systems can be geothermal heat, solar heat, surplus heat from industrial processes, and nuclear power.
Nuclear energy can be used for district heating. The principles for a conventional combination of cogeneration and district heating applies the same for nuclear as it does for a thermal power station
Thermal power station
A thermal power station is a power plant in which the prime mover is steam driven. Water is heated, turns into steam and spins a steam turbine which drives an electrical generator. After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was heated; this...
. Russia has several cogeneration nuclear plants which together provided 11.4 PJ of district heat in 2005. Russian nuclear district heating is planned to nearly triple within a decade as new plants are built.
Other nuclear powered heating from cogeneration plants are in the Ukraine, the Czech Republic, Slovakia, Hungary, Bulgaria, and Switzerland, producing up to about 100 MW per power station. One use of nuclear heat (now closed) generation was with the Ågesta Nuclear Power Plant
Ågesta Nuclear Power Plant
The nuclear power station Ågesta was the first Swedish commercial nuclear power plant. Construction started in 1957 and ended in 1962, operations began in 1964 and continued until 1974. The station primarily provided district heating for the Stockholm suburb Farsta, as well as a small amount of...
in Sweden.
In Switzerland, the Beznau Nuclear Power Plant
Beznau Nuclear Power Plant
The Beznau Nuclear Power Plant is located in the municipality Döttingen on an artificial island in the Aar river...
provides heat to about 20,000 people.
Heat distribution
Insulated pipes
Insulated pipes are widely used for district heating and hot water supply in Europe. They consist of a steel pipe, an insulating layer, and an outer casing. The main purpose of such pipes is to maintain the temperature of the fluid in the pipes. A common application is the hot water from district...
. District heating systems consists of feed and return lines. Usually the pipes are installed underground but there are also systems with overground pipes. Within the system heat storage
Thermal energy storage
Thermal energy storage comprises a number of technologies that store thermal energy in energy storage reservoirs for later use. They can be employed to balance energy demand between day time and night time. The thermal reservoir may be maintained at a temperature above or below that of the...
s may be installed to even out peak load demands.
The common medium used for heat distribution is water, but also steam
Steam
Steam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...
is used. The advantage of steam is that in addition to heating purposes it can be used in industrial process
Industrial process
Industrial processes are procedures involving chemical or mechanical steps to aid in the manufacture of an item or items, usually carried out on a very large scale. Industrial processes are the key components of heavy industry....
es due to its higher temperature. The disadvantage of steam is a higher heat loss due to the high temperature. Also, the thermal efficiency
Thermal efficiency
In thermodynamics, the thermal efficiency is a dimensionless performance measure of a device that uses thermal energy, such as an internal combustion engine, a boiler, a furnace, or a refrigerator for example.-Overview:...
of cogeneration plants is significantly lower if the cooling medium is high temperature steam, causing smaller electric power
Electric power
Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt.-Circuits:Electric power, like mechanical power, is represented by the letter P in electrical equations...
generation. Heat transfer oils are generally not used for district heating, although they have higher heat capacities than water, as they are expensive, and have environmental issues.
At customer level the heat network is usually connected to the central heating
Central heating
A central heating system provides warmth to the whole interior of a building from one point to multiple rooms. When combined with other systems in order to control the building climate, the whole system may be a HVAC system.Central heating differs from local heating in that the heat generation...
of the dwellings by heat exchanger
Heat exchanger
A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...
s (heat substations
District heating substation
thumb|right|A district heating substation in a residential neighborhood with a thermal capacity of 300 kW. Two components of the heat meter are visible: the metering electronics unit on the right , and the ultrasonic flow meter in the center .A district heating substation is a component in a...
). The water (or the steam) used in the district heating system is not mixed with the water of the central heating system of the dwelling. In the Odense system direct connection is used.
Typical annual loss of thermal energy through distribution is around 10%, as seen in Norway's district heating network.
Heat metering
Often heat is metered to customers using a Heat meterHeat meter
thumb|right|Heat meter in a [[District heating substation]] in a residential neighborhood. Right in whit-blue: the calculator; in the center in bronze: the ultrasonic flow meter...
, to encourage economy and maximise the number of customers which can be served, but these are expensive. Many communist-era systems were not metered, leading to great innefficiencies - users simply opened windows when too hot - wasting energy and minimising the numbers of connectable customers. Due to the expense of heat metering, an alternative approach is simply to meter the water - water meters are much cheaper than heat meters, and have the advantage of encouraging consumers to extract as much heat as possible, leading to a very low return temperature, which increases the efficiency of power generation.
Size of systems
District heating systems can vary in size from covering entire cities such as Stockholm or Flensburg with a network of Large meter diameter primary pipes linked to secondary pipes - 200 mm diameter perhaps, which in turn link to tertiary pipes of perhaps 25 mm diameter which might connect 10s to 50 houses.Some district heating schemes might only be sized to meet the needs of a small village or area of a city in which case only the secondary and tertiary pipes will be needed.
Some schemes may be designed to serve only a limited number of dwellings - 20 - 50 - in which case only tertiary sized pipes are needed.
Pros and cons
District heating has various advantages compared to individual heating systems. Usually district heating is more energy efficient, due to simultaneous production of heat and electricity in combined heat and power generation plants. The larger combustion units also have a more advanced flue gasFlue gas
Flue gas is the gas exiting to the atmosphere via a flue, which is a pipe or channel for conveying exhaust gases from a fireplace, oven, furnace, boiler or steam generator. Quite often, the flue gas refers to the combustion exhaust gas produced at power plants...
cleaning than single boiler systems. In the case of surplus heat from industries, district heating systems do not use additional fuel because they use heat (termed heat recovery) which would be dispersed to the environment.
District heating is a long-term commitment that fits poorly with a focus on short-term returns on investment. Benefits to the community include avoided costs of energy, through the use of surplus and wasted heat energy, and reduced investment in individual household or building heating equipment. District heating networks, heat-only boiler stations, and cogeneration plants require high initial capital expenditure and financing. Only if considered as long-term investments will these translate into profitable operations for the owners of district heating systems, or combined heat and power plant operators. District heating is less attractive for areas with low population densities, as the investment per household is considerably higher. Also it is less attractive in areas of many small buildings; e.g. detached houses than in areas with a few much larger buildings; e.g. blocks of flats, because each connection to a single-family house is quite expensive.
Ownership, monopoly issues and charging structures
In many cases large combined heat and power district heating schemes are owned by a single entity. This was typically the case in the old Eastern bloc countries. However the majority of schemes the ownership of the cogeneration plant is separate from the heat using part.Examples are Warsaw which has such split ownership with Vattenfall owning the cogeneration unit, and the municipality the heat distribution. Similarly all the large chp/ch schemes in Denmark are of split ownership.
Carbon footprint and cost of reduction
One study shows that District Heating with Combined Heat and Power has the lowest carbon footprint of any heating system, and it rapidly competes with extra insulation.National variation
Since conditions from city to city differ, every district heating system is uniquely constructed. In addition, nations have different access to primary energy carriers and so they have a different approach how to address the heating market within their borders.This leads not only to a different degree of diffusion but also to different district heating systems in general throughout the world.
Europe
Since 1954, district heating has been promoted in EuropeEurope
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
by Euroheat & Power. They have compiled an analysis of district heating and cooling markets in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
within their Ecoheatcool
Ecoheatcool
Launched at the beginning of 2005 with support from the , the ECOHEATCOOL project carried out by Euroheat & Power, in cooperation with 13 partners across Europe was concluded at the end of December 2006....
project supported by the European Commission
European Commission
The European Commission is the executive body of the European Union. The body is responsible for proposing legislation, implementing decisions, upholding the Union's treaties and the general day-to-day running of the Union....
. The legal framework in the member states of the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
is currently influenced by the EU-CHP Directive
CHP Directive
This refers to the Directive on the promotion of cogeneration based on a useful heat demand in the internal energy market and amending Directive 92/62/EEC, officially 2004/8/EC and popularly better known as the 'Combined Heat and Power Directive'...
.
Cogeneration in Europe
CHP Directive
This refers to the Directive on the promotion of cogeneration based on a useful heat demand in the internal energy market and amending Directive 92/62/EEC, officially 2004/8/EC and popularly better known as the 'Combined Heat and Power Directive'...
. In September 2008 at a hearing of the European Parliament’s Urban Lodgment Intergroup, Energy Commissioner Andris Piebalgs is quoted as saying, "security of supply really starts with energy efficiency." Energy efficiency and cogeneration are recognized in the opening paragraphs of the European Union’s Cogeneration Directive 2004/08/EC. This directive intends to support cogeneration and establish a method for calculating cogeneration abilities per country. The development of cogeneration has been very uneven over the years and has been dominated throughout the last decades by national circumstances.
As a whole, the European Union currently generates 11% of its electricity using cogeneration, saving Europe an estimated 35Mtoe per annum a day. However, there is large difference between Member States with variations of the energy savings between 2% and 60%. Europe has the three countries with the world’s most intensive cogeneration economies: Denmark, the Netherlands and Finland.
Other European countries are also making great efforts to increase their efficiency. Germany reported that at present, over 50% of the country’s total electricity demand could be provided through cogeneration. So far Germany has set the target to double its electricity cogeneration from 12.5% of the country’s electricity to 25% of the country’s electricity by 2020 and has passed supporting legislation accordingly in “Federal Ministry of Economics and Technology, (BMWi), Germany, August 2007. The UK is also actively supporting combined heat and power. In light of UK’s goal to achieve a 60% reduction in carbon dioxide emissions by 2050, the government has set the target to source at least 15% of its government electricity use from CHP by 2010. Other UK measures to encourage CHP growth are financial incentives, grant support, a greater regulatory framework, and government leadership and partnership.
According to the IEA 2008 modelling of cogeneration expansion for the G8 countries, expansion of cogeneration in France, Germany, Italy and the UK alone would effectively double the existing primary fuel savings by 2030. This would increase Europe’s savings from today’s155.69 Twh to 465 Twh in 2030. It would also result in a 16% to 29% increase in each country’s total cogenerated electricity by 2030.
Governments are being assisted in their CHP endeavors by organizations like COGEN Europe
COGEN Europe
COGEN Europe is a Brussels-based advocacy group that promotes the use of cogeneration . The organisation currently encompasses over 75 members from over 25 countries across Europe...
who serve as an information hub for the most recent updates within Europe’s energy policy. COGEN is Europe’s umbrella organization representing the interests of the cogeneration industry, users of the technology and promoting its benefits in the EU and the wider Europe. The association is backed by the key players in the industry including gas and electricity companies, ESCOs, equipment suppliers, consultancies, national promotion organisations, financial and other service companies.
Austria
The largest district heating system in AustriaAustria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
is in Vienna
Vienna
Vienna is the capital and largest city of the Republic of Austria and one of the nine states of Austria. Vienna is Austria's primary city, with a population of about 1.723 million , and is by far the largest city in Austria, as well as its cultural, economic, and political centre...
(Fernwärme Wien) - with many smaller systems distributed over the whole country.
District heating in Vienna is run by Wien Energie. In the business year of 2004/2005 a total of 5.163 GWh was sold, 1.602 GWh to 251.224 private apartments and houses and 3.561 GWh to 5211 major customers. The three large municipal waste incinerators
Incineration
Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into ash, flue gas, and...
provide 22 % of the total in producing 116 GWh electric power and 1.220 GWh heat. Waste heat from municipal power plants and large industrial plants account for 72 % of the total. The remaining 6 % is produced by peak heating boilers from fossil fuel. In the year 2006 the started the heat production also with a biomass fired power plant.
In the rest of Austria the newer district heating plants are constructed as biomass plant or as CHP-biomass plants like biomass district heating Mödling or the biomass district heating Baden.
The most older fossil fired district heating systems have a district heating accumulator, so that it is possible to produce the thermal district heating power only at that time where the electric power price is high.
Czech Republic
The largest district heating system in the Czech RepublicCzech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
is in Prague owned and operated by Prazska teplarenska, serving 265 thousands households and selling ca. 13 PJ of heat annually. There are many smaller central heating systems spread around the country. More information can be found at website of Association for the District Heating of the Czech Republic.
Denmark
In DenmarkDenmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
, district heating covers more than 60% of space heating
Space heating
A space heater is a self-contained device for heating an enclosed area. Space heating is generally employed to warm a small space, and is usually held in contrast with central heating, which warms many connected spaces at once...
and water heating
Water heating
Water heating is a thermodynamic process using an energy source to heat water above its initial temperature. Typical domestic uses of hot water are for cooking, cleaning, bathing, and space heating...
. In 2007, 80.5% of this heat was produced on combined heat and power
Combined Heat and Power
Combined Heat and Power may refer to:* Cogeneration* Combined Heat and Power Solar...
plants. Heat recovered from waste incineration
Incineration
Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into ash, flue gas, and...
accounted for 20.4% of the total Danish district heat production. Most major cities in Denmark have big district heating networks including transmission networks operation with up to 125°C and 25 bar pressure and distribution networks operating with up to 95°C and between 6 and 10 bar pressure. The largest district heating system in Denmark is in the Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...
area operated by CTR I/S and VEKS I/S. In central Copenhagen, the CTR network serves 275,000 households (90-95% of the area's population) through one network of 54-kilometer double district heating distribution pipes providing a peak capacity of 663 MW. The consumer price of heat from CTR is approximately €49 per MWh plus taxes (2009).
Finland
In Finland district heating accounts for about 50 per cent of the total heating market, 4/5 of which being produced from combined heat and powerCombined Heat and Power
Combined Heat and Power may refer to:* Cogeneration* Combined Heat and Power Solar...
plants. Over 90 per cent of apartment blocks, more than half of all terraced houses, and the bulk of public buildings and business premises are connected to a district heating network. Natural Gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
is mostly used in areas to the south east gas pipeline network, imported coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
is used in areas close to ports, and peat
Peat
Peat is an accumulation of partially decayed vegetation matter or histosol. Peat forms in wetland bogs, moors, muskegs, pocosins, mires, and peat swamp forests. Peat is harvested as an important source of fuel in certain parts of the world...
is used in northern areas where peat is a natural resource. However, other renewables such as wood chips and other paper industry combustible by-products are also used, as is the energy recovered by the incineration
Incineration
Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into ash, flue gas, and...
of municipal solid waste
Municipal solid waste
Municipal solid waste , commonly known as trash or garbage , refuse or rubbish is a waste type consisting of everyday items we consume and discard. It predominantly includes food wastes, yard wastes, containers and product packaging, and other miscellaneous inorganic wastes from residential,...
. Industrial units which generate heat as an industrial by-product may sell otherwise waste heat to the network rather than release it to the environment. In some towns, waste incineration can contribute as much as 8% of the district heating heat requirement. Availability
Availability
In telecommunications and reliability theory, the term availability has the following meanings:* The degree to which a system, subsystem, or equipment is in a specified operable and committable state at the start of a mission, when the mission is called for at an unknown, i.e., a random, time...
is 99.98% and disruptions when they do occur usually reduce temperatures by only a few degrees.
In Helsinki, an underground datacenter under the Uspenski Cathedral will release the excess heat into the homes of the neighbours, producing enough heat to heat approximately 500 large houses.
Germany
In GermanyGermany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
district heating has a market share of around 14 % in the residential buildings sector. The connected heat load is around 52.729 MW. The heat comes mainly from cogeneration plants (83 %). Heat-only boilers supply 16 % and 1 % is surplus heat from industry. The cogeneration plants use natural gas (42 %), coal (39 %), lignite (12 %) and waste/others (7 %) as fuel.
The largest district heating network is located in Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
whereas the highest diffusion of district heating occurs in Flensburg
Flensburg
Flensburg is an independent town in the north of the German state of Schleswig-Holstein. Flensburg is the centre of the region of Southern Schleswig...
with around 90% market share.
District heating has rather little legal framework in Germany. There is no law on it as most elements of district heating are regulated in governmental or regional orders. There is no governmental support for district heating networks but a law to support cogeneration plants. As in the European Union the CHP Directive
CHP Directive
This refers to the Directive on the promotion of cogeneration based on a useful heat demand in the internal energy market and amending Directive 92/62/EEC, officially 2004/8/EC and popularly better known as the 'Combined Heat and Power Directive'...
will come effective, this law probably needs some adjustment.
Iceland
With 95% of all housing (mostly in the capital of ReykjavikReykjavík
Reykjavík is the capital and largest city in Iceland.Its latitude at 64°08' N makes it the world's northernmost capital of a sovereign state. It is located in southwestern Iceland, on the southern shore of Faxaflói Bay...
) enjoying district heating services - mainly from geothermal energy, Iceland is the country with the highest penetration of district heating.
Most of the district heating in Iceland comes from three main geothermal power plants, producing over 800 MWth:
- Svartsengi combined heat and power plant (CHP)
- Nesjavellir CHP plant
- Hellisheiði CHP plant
Italy
In ItalyItaly
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, district heating is used in some cities (Bergamo
Bergamo
Bergamo is a town and comune in Lombardy, Italy, about 40 km northeast of Milan. The comune is home to over 120,000 inhabitants. It is served by the Orio al Serio Airport, which also serves the Province of Bergamo, and to a lesser extent the metropolitan area of Milan...
, Brescia
Brescia
Brescia is a city and comune in the region of Lombardy in northern Italy. It is situated at the foot of the Alps, between the Mella and the Naviglio, with a population of around 197,000. It is the second largest city in Lombardy, after the capital, Milan...
, Bolzano, Ferrara
Ferrara
Ferrara is a city and comune in Emilia-Romagna, northern Italy, capital city of the Province of Ferrara. It is situated 50 km north-northeast of Bologna, on the Po di Volano, a branch channel of the main stream of the Po River, located 5 km north...
, Reggio Emilia
Reggio Emilia
Reggio Emilia is an affluent city in northern Italy, in the Emilia-Romagna region. It has about 170,000 inhabitants and is the main comune of the Province of Reggio Emilia....
, Terlan
Terlan
Terlan is a comune in South Tyrol in the Italian region Trentino-Alto Adige/Südtirol, located about 50 km north of the city of Trento and about 9 km northwest of the city of Bolzano.-Geography:...
, Turin
Turin
Turin is a city and major business and cultural centre in northern Italy, capital of the Piedmont region, located mainly on the left bank of the Po River and surrounded by the Alpine arch. The population of the city proper is 909,193 while the population of the urban area is estimated by Eurostat...
, Lodi and now Milan
Milan
Milan is the second-largest city in Italy and the capital city of the region of Lombardy and of the province of Milan. The city proper has a population of about 1.3 million, while its urban area, roughly coinciding with its administrative province and the bordering Province of Monza and Brianza ,...
). The district heating of Turin is the biggest of the country and it supplies 550.000 people (55% of the whole city population).
Norway
In NorwayNorway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
district heating only constitutes approx. 2 % of energy needs for heating. This is a very low number compared to similar countries. One of the main reasons district heating has a low penetration in Norway is access to cheap hydro based electricity. However, there is district heating in the major cities.
Poland
The largest district heating system in PolandPoland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
is in Warsaw owned and operated by SPEC distributing approx. 34 PJ annually.
Romania
The largest district heating system in RomaniaRomania
Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...
is in Bucharest owned and operated by RADET distributing approx. 24 PJ annually, serving 570 thousands households. Central heating system of RADET provides 72% of the heat in Bucharest (68% by the means of centralized heating system, 4% from block heating plants).
Russia
In most RussiaRussia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
n cities, district-level combined heat and power
Combined Heat and Power
Combined Heat and Power may refer to:* Cogeneration* Combined Heat and Power Solar...
plants produce more than 50 % of the nation's electricity and simultaneously provide hot water for neighbouring city blocks. They mostly use coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
and oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
-powered steam turbine
Steam turbine
A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884....
s for cogeneration of heat. Now, gas turbine
Gas turbine
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between....
s and combined cycle
Combined cycle
In electric power generation a combined cycle is an assembly of heat engines that work in tandem off the same source of heat, converting it into mechanical energy, which in turn usually drives electrical generators...
designs are beginning to be widely used as well. A Soviet-era approach of using very large central stations to heat large districts of a big city or entire small cities is fading away as due to inefficiency, much heat is lost in the piping network because of leakage
Leakage
Leakage may refer to:*Leakage *Memory leak, in computer science*Leakage *Leakage *Leakage *Leakage...
s and lack of proper thermal insulation
Thermal insulation
Thermal insulation is the reduction of the effects of the various processes of heat transfer between objects in thermal contact or in range of radiative influence. Heat transfer is the transfer of thermal energy between objects of differing temperature...
.
Serbia
In SerbiaSerbia
Serbia , officially the Republic of Serbia , is a landlocked country located at the crossroads of Central and Southeast Europe, covering the southern part of the Carpathian basin and the central part of the Balkans...
, district heating is used throughout the main cities, particularly in the capital, Belgrade
Belgrade
Belgrade is the capital and largest city of Serbia. It is located at the confluence of the Sava and Danube rivers, where the Pannonian Plain meets the Balkans. According to official results of Census 2011, the city has a population of 1,639,121. It is one of the 15 largest cities in Europe...
.
The first district heating plant was built in 1961 as a means to provide effective heating to the newly built suburbs of Novi Beograd
Novi Beograd
Novi Beograd or New Belgrade is the most populous municipality that constitutes the City of Belgrade, the capital of Serbia. It is a planned city, built in 1947 on the left bank of the Sava river which was previously an uninhabited area, opposite of the old Belgrade...
.Since then numerous plants were built to heat the ever growing city.As fuel they use natural gas,because it has less of an effect on the environment.The district heating system of Belgrade possesses 112 heat sources of 2,454 MW capacity and by pipelines more than 500 km long and 4365 connection stations, providing district heating to 240,000 apartments and 7,500 office/commercial buildings of total floor area exceeding 17,000,000 square meters.
Sweden
SwedenSweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
has a long tradition for using district heating in urban areas.
The city of Växjö
Växjö
Växjö is a city and the seat of Växjö Municipality, Kronoberg County, Sweden with 64 200 inhabitants in 2010. It is the administrative, cultural and industrial centre of Kronoberg County. Furthermore it is the episcopal see of the Diocese of Växjö. It has a population of about 64 200, out of a...
has reduced its fossil fuel consumption by 30% in 1993-2006 and aims at 50% reduction in 2010. This is to a large extent to be achieved by way of biomass fired district heating
90% of the energy in Swedish district heating system are usually produced with renewable sources . The remaining 10 % are only used when the weather is really cold and there is a very high energy demand. Because of the law forbidding landfill , waste is commonly used as a fuel.
United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, district heating also became popular after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, but on a restricted scale, to heat the large residential estates that replaced areas devastated by the Blitz
The Blitz
The Blitz was the sustained strategic bombing of Britain by Nazi Germany between 7 September 1940 and 10 May 1941, during the Second World War. The city of London was bombed by the Luftwaffe for 76 consecutive nights and many towns and cities across the country followed...
. The photo (right) shows the accumulator at the Pimlico District Heating Undertaking (PDHU), just north of the River Thames
River Thames
The River Thames flows through southern England. It is the longest river entirely in England and the second longest in the United Kingdom. While it is best known because its lower reaches flow through central London, the river flows alongside several other towns and cities, including Oxford,...
. The PDHU first became operational in 1950 and continues to expand to this day. The PDHU once relied on waste heat from the now-disused Battersea Power Station
Battersea Power Station
Battersea Power Station is a decommissioned coal-fired power station located on the south bank of the River Thames, in Battersea, South London. The station comprises two individual power stations, built in two stages in the form of a single building. Battersea A Power Station was built first in the...
on the South side of the River Thames
River Thames
The River Thames flows through southern England. It is the longest river entirely in England and the second longest in the United Kingdom. While it is best known because its lower reaches flow through central London, the river flows alongside several other towns and cities, including Oxford,...
. It is still in operation, the water now being heated locally by a new energy centre which incorporates 3.1 MWe /4.0 MWTh of gas fired CHP engines and 3 x 8 MW gas fired boilers.
One of the United Kingdom's largest district heating schemes is EnviroEnergy in Nottingham
Nottingham
Nottingham is a city and unitary authority in the East Midlands of England. It is located in the ceremonial county of Nottinghamshire and represents one of eight members of the English Core Cities Group...
. Plant initially built by Boots is now used to heat 4,600 homes, and a wide variety of business premises, including the Concert Hall
Nottingham Royal Concert Hall
The Royal Concert Hall in the English city of Nottingham, is part of the city's Royal Centre, which also incorporates the Victorian Theatre Royal...
, the Nottingham Arena, the Victoria Baths, the Broadmarsh Shopping Centre
Broadmarsh Shopping Centre
Westfield Broadmarsh is a shopping centre in Nottingham, England, owned by the Australian company The Westfield Group. The centre has 86 stores and a total retail floor space of 45,000 m² . The main retailers are Argos, Bhs, Boots, H&M, with other stores such as JD Sports, Wilkinson...
, the Victoria Centre and others. The heat source is a Waste-to-energy
Waste-to-energy
Waste-to-energy or energy-from-waste is the process of creating energy in the form of electricity or heat from the incineration of waste source. WtE is a form of energy recovery...
incinerator.http://www.enviroenergy.co.uk/ Scotland has several district heating systems with the first in the UK being installed at Aviemore and others following at Lochgilphead, Fort William and Forfar.
Another significant scheme is in Southampton
Southampton
Southampton is the largest city in the county of Hampshire on the south coast of England, and is situated south-west of London and north-west of Portsmouth. Southampton is a major port and the closest city to the New Forest...
. It was originally built to use geothermal
Geothermal heating
Geothermal heating is the direct use of geothermal energy for heating applications. Humans have taken advantage of geothermal heat this way since the Paleolithic era. Approximately seventy countries made direct use of a total of 270 PJ of geothermal heating in 2004...
energy, but now also uses the heat from a gas fired CHP generator. It supplies heat to many large premises in the city, including the WestQuay shopping centre, the De Vere Grand Harbour hotel, the Royal South Hants Hospital and several housing schemes.
Many other such heating plants still operate on estates across Britain. Though they are said to be efficient, a frequent complaint of residents is that the heating levels are often set too high - the original designs did not allow for individual users to have their own thermostat
Thermostat
A thermostat is the component of a control system which regulates the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature. The thermostat does this by switching heating or cooling devices on or off, or regulating the flow of a heat transfer...
s.
Spain
The largest District Heating System in Spain is located in Soria. Is called 'Ciudad del Medio Ambiente' (Environmental Town) and it will have 41MW from a biomass power plant.North America
In North AmericaNorth America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, district heating systems fall into two general categories. Those that are owned by and serve the buildings of a single entity are considered institutional systems. All others fall into the commercial category.
Canada
District Heating is becoming a growing industry in Canadian cities, with many new systems being built in the last ten years. Some of the major systems in Canada include:- Montreal, QC has a district heating and cooling system in the downtown core.
- Toronto, ON - EnwaveEnwaveEnwave is a private corporation jointly owned by the City of Toronto and the Ontario Municipal Employees Retirement System and is one of the largest district energy systems in North America...
provides district heating and cooling within the downtown core of TorontoTorontoToronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
, including deep lake cooling technology, which circulates cold water from Lake Ontario through heat exchangers to provide cooling for many buildings in the city. - Calgary, AB: ENMAXENMAXENMAX Corporation is a vertically integrated utility that provides electricity, natural gas, renewable energy and value-added services to its customers.-Overview:...
is currently building its Calgary Downtown District Energy Centre which will provide heating to up to 10000000 square feet (929,030.4 m²) of new and existing residential and commercial buildings. Construction of the Calgary Downtown District Energy Centre has begun with commercial operation anticipated for March 2010. - Vancouver, BC:
- Central Heat Distribution Ltd.Central Heat DistributionCentral Heat Distribution Ltd. is a private district heating company located at 720 Beatty Street in Vancouver, Canada that provides heat to the Downtown Core including the Vancouver Public Library Central Branch, B.C...
operates a central heating plant in the downtown core of VancouverVancouverVancouver is a coastal seaport city on the mainland of British Columbia, Canada. It is the hub of Greater Vancouver, which, with over 2.3 million residents, is the third most populous metropolitan area in the country,...
, British ColumbiaBritish ColumbiaBritish Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
. In addition to building heating, the Central Heat Distribution network also drives a steam clockSteam clockA steam clock is a clock which is fully or partially powered by a steam engine. Only a few functioning steam clocks exist, most designed and built by Canadian horologist Raymond Saunders for display in urban public spaces...
. - A large scale district heating system known as the Neighbourhood Energy Utility in the South East False Creek area is in initial operations with natural gas boilers and serves the 2010 Olympic Village. The commissioning of an innovative untreated sewage heat recovery system anticipated for January 2010 is expected to supply 70% of annual energy demands and reduce greenhouse gas emissions.
- Central Heat Distribution Ltd.
- Windsor, ON has a district heating and cooling system in the downtown core.
- Drake Landing, AB, is small in size (52 homes) but notable for having the only central solar heatingCentral solar heatingCentral solar heating is the provision of central heating and hot water from solar energy by a system in which the water is heated centrally by arrays of solar thermal collectors and distributed through district heating pipe networks .For block systems, the solar collectors are...
system in North America. - London, Ontario and Charlottetown, PEI have district heating co-generation systems owned and operated by Fort Chicago Energy Partners L.P.
- Sudbury, Ontario has a district heating cogeneration system in its downtown core, as well as a standalone cogeneration plant for the Sudbury Regional HospitalSudbury Regional HospitalHealth Sciences North is a hospital located on 41 Ramsey Lake Road in the city of Sudbury, Ontario, Canada.The HSN, formerly the Sudbury Regional Hospital , was established in the 1990s as part of provincial health care restructuring program by the Mike Harris government...
. In addition, Naneff Gardens, a new residential subdivision off Donnelly Drive in the city's Garson neighbourhood, features a geothermal district heating system using technology developed by a local company, Renewable Resource Recovery Corporation.
Many Canadian universities operate central campus heating plants.
United States
Consolidated EdisonConsolidated Edison
Consolidated Edison, Inc. is one of the largest investor-owned energy companies in the United States, with approximately $14 billion in annual revenues and $36 billion in assets...
of New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
(Con Ed) operates the New York City steam system
New York City steam system
The New York City steam system is a district heating system which takes steam produced by steam generating stations and carries it under the streets of Manhattan to heat, cool, or supply power to high rise buildings and businesses...
, the largest commercial district heating system in the United States. The system has operated continuously since March 1882 and serves Manhattan Island from the Battery through 96th Street. In addition to providing space- and water-heating, steam from the system is used in numerous restaurants for food preparation, for process heat in laundries and dry cleaners, and to power absorption chillers for air conditioning
Air conditioning
An air conditioner is a home appliance, system, or mechanism designed to dehumidify and extract heat from an area. The cooling is done using a simple refrigeration cycle...
.
On July 18, 2007, one person was killed and numerous others injured when a steam pipe exploded
2007 New York City steam explosion
The July 18, 2007 New York City steam explosion sent a geyser of hot steam up from beneath a busy intersection, with a 40-story-high shower of mud and flying debris raining down on the crowded streets of Midtown Manhattan in New York City, New York, United States.It was caused by the failure of a...
on 41st Street at Lexington. On August 19, 1989, three people were killed in an explosion in Gramercy Park.
- Denver's district steam system is the oldest continuously operated commercial district heating system in the world. It began service November 5, 1880 and continues to serve 135 customers. The system is partially powered by the Xcel EnergyXcel EnergyXcel Energy, Inc. is a public utility company based in Minneapolis, Minnesota, serving customers in Colorado, Michigan, Minnesota, New Mexico, North Dakota, South Dakota, Texas, and Wisconsin. Primary services are electricity and natural gas...
Zuni CogenerationCogenerationCogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....
Station, which was originally built in 1900. - NRG EnergyNRG EnergyNRG Energy, Inc. is an American energy company headquartered in West Windsor Township, New Jersey, near Princeton.-Electrical Power Generation Operations:...
operates district systems in the cities of San Francisco, Harrisburg, Minneapolis, Pittsburgh and San Diego. - Seattle Steam CompanySeattle Steam CompanyThe Seattle Steam Company is a privately owned district heating public utility that provides steam to over 175 business in downtown Seattle and on First Hill via 18 miles of steam pipeline...
operates a district system in Seattle. - Detroit EdisonDetroit EdisonThe Detroit Edison Company, founded in 1903, is an investor-owned electric utility which serves most of Southeast Michigan. Its parent company, DTE Energy , provides energy services to a variety of clients beyond Detroit Edison's service area.- History :...
operates a district system in Detroit that started operation at the Willis Avenue Station in 1903. - Lansing Board of Water and Light, a municipal utility system in Lansing, MI operates a heated and chilled water system from their existing coal plant. They have announced their new natural gas cogeneration plant will continue to provide this service.
- Cleveland Thermal operates a district steam (since 1894) from the Canal Road plant near The Flats and district cooling system (since 1993) from Hamilton Avenue plant on the bluffs east of downtown.
- Fort Chicago Energy Partners L.P. operate district heating/co-generation plants in Ripon, CaliforniaRipon, CaliforniaRipon is a city located in . The population was 14,297 at the 2010 census.-History:Ripon, on the site previously known as Murphy's Ferry, Stanislaus City, & Stanislaus Station, was renamed for , which was itself named for a city in Yorkshire, England...
and San Gabriel, CaliforniaSan Gabriel, CaliforniaSan Gabriel is a city in Los Angeles County, California, United States. It is named after the Mission San Gabriel Arcángel, founded by Junipero Serra. The city grew outward from the mission and in 1852 became the original township of Los Angeles County. San Gabriel was incorporated in 1913...
. - Veolia Energy, a successor of the 1887 Boston Heating Company, operates a 26 miles (41.8 km) district system in BostonBostonBoston is the capital of and largest city in Massachusetts, and is one of the oldest cities in the United States. The largest city in New England, Boston is regarded as the unofficial "Capital of New England" for its economic and cultural impact on the entire New England region. The city proper had...
and CambridgeCambridge, MassachusettsCambridge is a city in Middlesex County, Massachusetts, United States, in the Greater Boston area. It was named in honor of the University of Cambridge in England, an important center of the Puritan theology embraced by the town's founders. Cambridge is home to two of the world's most prominent...
, MassachusettsMassachusettsThe Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
and also operates systems in Philadelphia PA, Baltimore MD, Kansas City KS, Tulsa OK, Houston TX and other cities. - District Energy St. Paul operates the largest hot water district heating system in North America and generates the majority of its energy from an adjacent biomass-fueled combined heat and power plant. In March 2011, a 1 MWh thermal solar array was integrated into the system, consisting of 144 20' x 8' solar panels installed on the roof of a customer building, RiverCentre.
District heating is also used on many college campuses, Including the University of Texas at Austin, which also provides district cooling and can generate all of the electricity used on campus, the University of Notre Dame
University of Notre Dame
The University of Notre Dame du Lac is a Catholic research university located in Notre Dame, an unincorporated community north of the city of South Bend, in St. Joseph County, Indiana, United States...
, Michigan State University
Michigan State University
Michigan State University is a public research university in East Lansing, Michigan, USA. Founded in 1855, it was the pioneer land-grant institution and served as a model for future land-grant colleges in the United States under the 1862 Morrill Act.MSU pioneered the studies of packaging,...
, University of Maryland, College Park
University of Maryland, College Park
The University of Maryland, College Park is a top-ranked public research university located in the city of College Park in Prince George's County, Maryland, just outside Washington, D.C...
, which produce over half their own electricity and all of their heating needs from a single plant on their respective campuses. MIT installed a cogeneration system in 1995 that provides electricity, heating and cooling to 80% of its campus buildings. The University of New Hampshire
University of New Hampshire
The University of New Hampshire is a public university in the University System of New Hampshire , United States. The main campus is in Durham, New Hampshire. An additional campus is located in Manchester. With over 15,000 students, UNH is the largest university in New Hampshire. The university is...
has a cogeneration plant run on methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
from an adjacent landfill, providing the University with 100% of its heat and power needs without burning oil or natural gas.
Japan
87 district heating enterprises are operating in JapanJapan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, serving 148 districts.
Many companies operate district cogeneration facilities that provide steam and/or hot water to many of the office buildings. Also, most operators in the Greater Tokyo serve district cooling.
History
District heating traces its roots to the hot water-heated baths and greenhouses of the ancient Roman EmpireRoman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....
. District systems gained prominence in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
during the Middle Ages
Middle Ages
The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...
and Renaissance
Renaissance
The Renaissance was a cultural movement that spanned roughly the 14th to the 17th century, beginning in Italy in the Late Middle Ages and later spreading to the rest of Europe. The term is also used more loosely to refer to the historical era, but since the changes of the Renaissance were not...
, with one system in France in continuous operation since the 14th century. The U.S. Naval Academy in Annapolis began steam
Steam
Steam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...
district heating service in 1853.
Although these and numerous other systems have operated over the centuries, the first commercially successful district heating system was launched in Lockport
Lockport
- Places :In Canada:* Lockport, Manitoba* Lockeport, Nova ScotiaIn the United States of America:* Lockport, Illinois* Lockport, Indiana* Lockport, Kentucky in Henry County, Kentucky* Lockport, Louisiana* Lockport , New York...
, New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
, in 1877 by American hydraulic engineer Birdsill Holly
Birdsill Holly
Birdsill Holly was an inventor. Holly was born in Auburn, New York. He spent his early years in Seneca Falls, New York, a major center of water powered industries. His first patented invention was a rotary water pump.-Life:...
, considered the founder of modern district heating.
Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
has been using geothermal heating
Geothermal heating
Geothermal heating is the direct use of geothermal energy for heating applications. Humans have taken advantage of geothermal heat this way since the Paleolithic era. Approximately seventy countries made direct use of a total of 270 PJ of geothermal heating in 2004...
from a 55-70 °C source 1–2 km below the surface since the 1970s for domestic heating.
In the 1980s Southampton
Southampton
Southampton is the largest city in the county of Hampshire on the south coast of England, and is situated south-west of London and north-west of Portsmouth. Southampton is a major port and the closest city to the New Forest...
began utilising combined heat and power district heating, taking advantage of geothermal heat "trapped" in the area. The geothermal heat provided by the well works in conjunction with the Combined Heat and Power scheme. Geothermal energy provides 15-20 %, fuel oil
Fuel oil
Fuel oil is a fraction obtained from petroleum distillation, either as a distillate or a residue. Broadly speaking, fuel oil is any liquid petroleum product that is burned in a furnace or boiler for the generation of heat or used in an engine for the generation of power, except oils having a flash...
10 %, and natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
70 % of the total heat input for this scheme and the combined heat and power generators use conventional fuels to make electricity. "Waste heat" from this process is recovered for distribution through the 11 km mains network.
The future of many of these systems are in doubt. The same kind of problems many district heating operations in former Soviet Union and Eastern Europe have today, many North American steam district heating systems began to experience in the 1960s and 1970s. In North America, the owners (in many cases power utilities) lost interest in the district heating business and provided insufficient funding for maintenance, and the systems and service to customers started to deteriorate. The result was that the systems started losing customers. The reliability decreased and finally the whole system closed down. For example, in Minnesota in the 1950s there were about 40 district steam systems, but today only a few remain.
Market penetration of district heating
Penetration of district heating (DH) into the heat market varies by country. Penetration is influenced by different factors, including environmental conditions, availability of heat sources, economics, and economic and legal framework.In the year 2000 the percentage of houses supplied by district heat in some European countries was as follows:
| Country | Penetration (2000) |
|---|---|
| Iceland | 95% |
| Denmark | 60% (2005) |
| Estonia | 52% |
| Poland | 52% |
| Sweden | 50% |
| Czech Rep. | 49% |
| Finland | 49% |
| Slovakia | 40% |
| Hungary | 16% |
| Austria | 12.5% |
| Germany | 12% |
| Netherlands | 3% |
| UK | 1% |
In Iceland the prevailing positive influence on DH is availability of easily captured geothermal heat. In most East European countries energy planning included development of cogeneration
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....
and district heating. Negative influence in The Netherlands and UK can be attributed partially to milder climate and also competition from natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
supply.
Energy consumption
According to Helsingin Energia, consumption of energy by district heating in Helsinki since 1970 peaked in 1971, at 67 kWh/m³/year, falling to 43 kWh/m³/year in 1997, since when it has not fluctuated greatly.Figures for Sweden suggest that the average Swede using district heating receives 4500 kWh/year from the system.
District cooling
The opposite of district heating is district cooling. Working on broadly similar principles to district heating, district cooling delivers chilled water to buildings like offices and factories needing cooling. In winter, the source for the cooling can often be sea water, so it is a cheaper resource than using electricity to run compressors for cooling.The Helsinki district cooling system uses otherwise wasted heat from summer time CHP power generation units to run absorption refrigerator
Absorption refrigerator
An absorption refrigerator is a refrigerator that uses a heat source to provide the energy needed to drive the cooling system...
s for cooling during summer time, greatly reducing electricity usage. In winter time, cooling is achieved more directly using sea water. The adoption of district cooling is estimated to reduce the consumption of electricity for cooling purposes by as much as 90 per cent and an exponential growth in usage is forecast. The idea is now being adopted in other Finnish cities. The use of district cooling grow also rapidly in Sweden in a similar way.
Cornell University
Cornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
's Lake Source Cooling System uses Cayuga Lake
Cayuga Lake
Cayuga Lake is the longest of central New York's glacial Finger Lakes, and is the second largest in surface area and second largest in volume. It is just under 40 miles long. Its average width is 1.7 miles , and it is at its widest point near Aurora...
as a heat sink to operate the central chilled water system for its campus and to also provide cooling to the Ithaca City School District. The system has operated since the summer of 2000 and was built at a cost of $55–60 million. It cools a 14,500 tons load.
In August 2004, Enwave Energy Corporation, a district energy company based in Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, started operating a system that uses water from Lake Ontario
Lake Ontario
Lake Ontario is one of the five Great Lakes of North America. It is bounded on the north and southwest by the Canadian province of Ontario, and on the south by the American state of New York. Ontario, Canada's most populous province, was named for the lake. In the Wyandot language, ontarío means...
to cool downtown buildings, including office towers, the Metro Toronto Convention Centre, a small brewery and a telecommunications centre. The process has become known as Deep Lake Water Cooling
Deep lake water cooling
Deep lake water cooling uses cold water pumped from the bottom of a lake as a heat sink for climate control systems. Because heat pump efficiency improves as the heat sink gets colder, deep lake water cooling can reduce the electrical demands of large cooling systems where it is available...
(DLWC). It will provide for over 40,000 tons (140 megawatts) of cooling—a significantly larger system than has been installed elsewhere. Another feature of the Enwave system is that it is integrated with Toronto’s drinking water supply. The Toronto drinking water supply required a new intake location that would be further from shore and deeper in the lake. This posed two problems for the utility that managed the city's drinking water supply: 1. the capital cost of moving the water intake location and additionally, the new location would supply water that was so cold it would require heating before it could be distributed. The cooperation of the district cooling agency, Enwave, solved both problems: Enwave paid for the cost of moving the water intake and also supplied the heat to warm the drinking water supply to acceptable levels by effectively extracting the heat from the buildings it served. Contact between drinking water and the Enwave cooling system is restricted to thermal contact in a heat exchanger. Drinking water does not circulate through the Enwave cooling systems.
In January 2006, PAL technology is one of the emerging project management companies in UAE involved in the diversified business of desalination, sewage treatment and district cooling system. More than 400,000 Tons of district cooling projects are planned. The Palm Jumeirah utilises district cooling to provide air conditioning.
In 2006, a district cooling system came online in Amsterdam's Zuidas, drawing water from the Nieuwe Meer
On the 10th of November 2010, The world's largest district cooling plant opened at The Pearl-Qatar. It is capable of cooling a load of 130,000 tons.
If the other renewable alternatives are too warm during the summer or too expensive, cold storage can be investigated. In large scale applications underground and snow storage are the most likely alternatives. In an underground storage the winter cold is heat exchanged from the air and loaded into the bedrock or an aquifer by one or more bore holes. In a snow storage frozen water (snow and/or ice) is saved in some kind of storage (pile, pit, cavern etc). The cold is utilized by pumping melt water to the cooling object, directly in a district cooling system or indirect by a heat exchanger. The luke warm melt water is then pumped back to the snow where it gets cooled and mixed with new melt water. Snow cooling works as a single cold source but can also be used for peak cooling since there is no relevant cooling limit. In Sweden there is one snow cooling plant in Sundsvall, built and owned by the county. The cooling load in Sundsvall is about 2000 kW (570 000 tons of refrigeration) and 1500 MWh/year.
See also
- Central solar heatingCentral solar heatingCentral solar heating is the provision of central heating and hot water from solar energy by a system in which the water is heated centrally by arrays of solar thermal collectors and distributed through district heating pipe networks .For block systems, the solar collectors are...
- CHP DirectiveCHP DirectiveThis refers to the Directive on the promotion of cogeneration based on a useful heat demand in the internal energy market and amending Directive 92/62/EEC, officially 2004/8/EC and popularly better known as the 'Combined Heat and Power Directive'...
- Geothermal heatingGeothermal heatingGeothermal heating is the direct use of geothermal energy for heating applications. Humans have taken advantage of geothermal heat this way since the Paleolithic era. Approximately seventy countries made direct use of a total of 270 PJ of geothermal heating in 2004...
- Lists of public utilities
- List of district heating systems
- New York City steam systemNew York City steam systemThe New York City steam system is a district heating system which takes steam produced by steam generating stations and carries it under the streets of Manhattan to heat, cool, or supply power to high rise buildings and businesses...
- Public utilityPublic utilityA public utility is an organization that maintains the infrastructure for a public service . Public utilities are subject to forms of public control and regulation ranging from local community-based groups to state-wide government monopolies...
- Seasonal thermal storeSeasonal thermal storeA seasonal thermal store is a store designed to retain heat deposited during the hot summer months for use during colder winter weather...
- Thermal energy storageThermal energy storageThermal energy storage comprises a number of technologies that store thermal energy in energy storage reservoirs for later use. They can be employed to balance energy demand between day time and night time. The thermal reservoir may be maintained at a temperature above or below that of the...
- Deep lake water coolingDeep lake water coolingDeep lake water cooling uses cold water pumped from the bottom of a lake as a heat sink for climate control systems. Because heat pump efficiency improves as the heat sink gets colder, deep lake water cooling can reduce the electrical demands of large cooling systems where it is available...
- Energy policy of the European UnionEnergy policy of the European UnionAlthough the European Union has legislated in the area of energy policy for many years, and evolved out of the European Coal and Steel Community, the concept of introducing a mandatory and comprehensive European energy policy was only approved at the meeting of the European Council on 27 October...
- Euroheat & powerEuroheat & PowerEuroheat & Power is a pan-European trade association of district heating operators and related companies and associations.Euroheat & Power unites the combined heat and power, district heating and cooling sector throughout Europe and beyond, with members from over thirty countries: including...
- Relative cost of electricity generated by different sources
- CogenerationCogenerationCogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....
External links
- The Combined Heat & Power Association
- The UK District Energy Association
- UK's Information Portal on Decentralised and District Energy
- Euroheat & Power: European District Heating & Cooling Association
- District Energy Library
- Technical description of district heating and district cooling at Munich Airport, Germany
- Helsinki district cooling system
- Danish Board of District Heating: Denmark's District Heating & Cooling Organisation
- Concord Steam Company, Concord, NH, USA
- Geothermal District Heating, Iceland
- Future Challenges for CHP in the UK and Continental Europe, Feb 2010 by F.Starr
- Euroheat - The international association of district heating & cooling
- COGEN Europe - The European trade association for the promotion of cogeneration
- Large Scale Solar Heating in Denmark