Zero emission refers to an engine

Engine

An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...

, motor

Electric motor

An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

, or other energy source, that emits no waste products that pollutes the environment or disrupts the climate.

Zero emission engines

Vehicles and other mobile machinery used for transport (over land, sea, air, rail) and for other uses (agricultural, mobile power generation, etc) contribute heavily to climate change and pollution, so zero emission engines are an area of active research. These technologies almost in all cases include an electric engine

Electric motor

An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

 powered by an energy source compact enough to be installed in the vehicle. These sources include hydrogen fuel cells, batteries, supercapacitors, and flywheel energy storage

Flywheel energy storage

Flywheel energy storage works by accelerating a rotor to a very high speed and maintaining the energy in the system as rotational energy...

 devices.

In some cases, such as compressed air engines, the engine may be mechanical rather than electrical. This mechanical engine is then powered by a passive energy source like compressed air

Compressed air

Compressed air is air which is kept under a certain pressure, usually greater than that of the atmosphere. In Europe, 10 percent of all electricity used by industry is used to produce compressed air, amounting to 80 terawatt hours consumption per year....

, or a combustible non-polluting gas like hydrogen

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

.

The above engines can be used in all vehicles, from cars to boats to propeller airplanes. For boats, energy sources such 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...

 and solar panels

Photovoltaics

Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material...

 can also be a viable option, in addition to traditional sail

Sail

A sail is any type of surface intended to move a vessel, vehicle or rotor by being placed in a wind—in essence a propulsion wing. Sails are used in sailing.-History of sails:...

s and turbosail

Turbosail

-Concept:In 1980, Jacques Cousteau dreamed of creating a ship with a modern engine that would be powered, at least in part, by the wind, a clean, free, renewable energy source...

s.

A concept like vegetable oil economy

Vegetable oil economy

Vegetable oil economy deals with the potential of vegetable oil to replace fossil fuels in the economy and how it compares to other potential replacements, including renewable electricity. Vegetable oils are the basis of biodiesel, which can be used like conventional diesel...

 produces emissions; however, the only emissions are things that were first taken out of the atmosphere when the plants were growing. So there is no net emission.

See also

• Air engine
• Carbon neutrality
• Zero emission project
• Zero Emissions Research and Initiatives
  Zero Emissions Research and Initiatives
  Zero Emissions Research and Initiatives was established by Gunter Pauli in 1994 at the United Nations University with the support of the Japanese Government...
  
  
• Zero-emissions vehicle
  Zero-emissions vehicle
  A zero-emissions vehicle, or ZEV, is a vehicle that emits no tailpipe pollutants from the onboard source of power. Harmful pollutants to the health and the environment include particulates , hydrocarbons, carbon monoxide, ozone, lead, and various oxides of nitrogen. Although not considered emission...
  
  

External links

• A special issue of the Journal of Cleaner Production that focuses specifically on Zero Emissions
• Description of what 'zero emission' means