Start-stop system
Encyclopedia
In automobile
s, a start-stop system or stop-start system automatically shuts down and restarts the internal combustion engine
to reduce the amount of time the engine spends idling
, thereby improving fuel economy
and reducing emissions. This is most advantageous for vehicles which spend significant amounts of time waiting at traffic lights or frequently come to a stop in traffic jams. This feature is present in hybrid electric vehicle
s, but has also appeared in vehicles which lack a hybrid electric powertrain
. For non-electric vehicles (called micro-hybrids,) fuel economy
gains from this technology are typically in the range of 5 to 10 percent.
Since automobile accessories like air conditioners and water pumps have typically been designed to run off a serpentine belt
on the engine, those systems must be redesigned to function properly when the engine is turned off. Typically, an electric motor is used to power these devices instead.
This technology has also been used on Honda Motor scooters in Asian markets for the last decade. Their PCX 125cc model was released in 2010 to be sold in Europe with this technology, though their North American model does not feature it.
Some of the earliest production vehicles to use this technology were the Volkswagen Polo
"Formel E" and Fiat Regata
"ES" models of the 1980s. The Volkswagen Group
also adopted it in the Golf
Ecomatic in 1994 and in the Volkswagen Lupo "3L" and the Audi A2 "3L" in 1999. Though these early implementations were considered rather disconcerting by many drivers, and high pricing failed to yield these cars much commercial success, both the Volkswagen Lupo and the Audi A2 (in their "3 litre" leverage) still hold the world record for most fuel efficient production car to date.
Citroën
introduced a more refined system in its C2
and C3
models by 2006, named "Stop and Start". The Citroën implementation combines a SensoDrive automated gearbox and an electronically controlled reversible alternator or integrated starter-generator (ISG). An ISG, also known as "integrated starter-alternator", combines the role of the starter
and alternator into one unit;
manufacturers include Valeo
and Denso
.
BMW
is including the technology across many of its cars and the MINI
line for 2008 as part of its Efficient Dynamics brand. BMW has been interested in ways to reduce parasitic loss
es on engines, so the company took the technology a step further. Instead of using an integrated starter generator, BMW has used an enhanced-starter which is nothing more than a conventional starter, developed by Robert Bosch GmbH
, that can withstand the increased number of engine-starts in a stop-start vehicle. BMW has developed the system such that the alternator is not activated most of the time. This means that electrical components in the vehicle are normally running on battery
power. When the battery needs to be charged or when decelerating or braking, the alternator is activated to recharge the battery (regenerative braking). Since this battery experiences very different load characteristics than a normal car battery, BMW used an absorptive glass mat type instead. Due to the use of regenerative braking, some have started calling this type of system a micro hybrid, a step below a mild hybrid
system where the ISG can be used to assist the engine or even drive the vehicle.
Toyota has been selling cars with start-stop system for several years in Japan. Both Toyota and Mazda
will be introducing stop-start technology available also outside of Japan in some of their 2009 model year vehicles, and Renault will introduce the technology in all of its European models by 2010.
The i-Stop system, Mazda
’s first start stop system, detects which piston is in the best position to restart quickest, which is the one in the combustion stroke phase, where air and fuel are in the cylinder, ready to be ignited. The mixture in this cylinder is ignited by the spark plug, forcing that piston down, resulting in a near instantaneous engine start time of 0.35 seconds.
In 2011, Mazda has announced i-ELOOP, a system which uses a variable-voltage alternator
to convert kinetic energy to electric power during deceleration. The energy stored in a double-layer capacitor, is used to supply power needed by vehicle electrical systems. When used in conjunction with Mazda’s start-stop system, i-Stop, the company claims fuel savings of up to 10%.
Honda
has been using this technology for over a decade. This was seen on the first gen Insight models sold in the Japanese domestic market (JDM) since 1999.
Fiat introduced the Robert Bosch GmbH made system in the end of 2008 in Fiat 500
, while Volvo introduced it in 2009 in its DRIVe models.
Starting September 2009, Alfa Romeo
also introduced this system in its Alfa Romeo Mito
series utilising Fiat Powertrain Technologies' (FPT) 1.4 L Turbo petrol MultiAir engines.
Mahindra's were the first in India to launch Stop Start based Micro Hybrid system. This involves home-grown technology and first of its kind component development like Hall sensor based neutral and clutch pedal sensors. Mahindra & Mahindra introduced the stop start based Micro Hybrid system to Indian Automotive market. This involved home grown technology for vehicles with mechanical fuel injection and later JV with BOSCH for common rail based vehicles.
Tata Motors has later introduced this system on their LCV Tata Ace
.
Late in 2010, Ford announced that its start-stop system, already used in its hybrids as well as several mainstream models in Europe, would be introduced in North America with the 2012 models, initially with 4-cylinder engines and later proliferating into V6s and V8s. Eventually the system will be available in all Ford vehicles.
The redesigned 2012 Kia Rio and Rio5 (hatchback) debuted at the 2011 New York Auto Show was announced with their Idle Stop and Go (ISG) feature, or stop-start technology. Kia claims the combination of direct fuel injection and stop-start will offer 30MPG City/40MPG on the highway in both 6 speed manual and automatic transmissions. While both the Kia Rio and Rio5 share the same new direct-injected four-cylinder 1.6L engine with it's cousin Hyundai Accent/Verna (also newly redesigned for 2012), Hyundai made no mention of this feature in their Accent line.
Hybrid/electric assist vehicles experience almost no delay in power from a stop, due to the instant availability of power from the traction battery to the electric motor(s). Gasoline/microhybrids on the other hand generally experience slight delays (albeit fractions of a sec).
Many people think that long term use may wear the components in Start-Stop implementations which require a starter motor, but this is not true. Mazda
i-stop used in their Mazda3/Axela line (in Europe and JDM) uses combustion to restart their engine by sensing the position of the piston in the cylinder. They claim quieter and quicker engine restart within 0.35 seconds.
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
s, a start-stop system or stop-start system automatically shuts down and restarts the internal combustion engine
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
to reduce the amount of time the engine spends idling
Idle speed
Idle speed is the rotational speed the engine runs on when the engine is uncoupled to the drivetrain and the throttle pedal isn't depressed of a combustion engine...
, thereby improving fuel economy
Fuel economy in automobiles
Fuel usage in automobiles refers to the fuel efficiency relationship between distance traveled by an automobile and the amount of fuel consumed....
and reducing emissions. This is most advantageous for vehicles which spend significant amounts of time waiting at traffic lights or frequently come to a stop in traffic jams. This feature is present in hybrid electric vehicle
Hybrid electric vehicle
A hybrid electric vehicle is a type of hybrid vehicle and electric vehicle which combines a conventional internal combustion engine propulsion system with an electric propulsion system. The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional...
s, but has also appeared in vehicles which lack a hybrid electric powertrain
Powertrain
In a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...
. For non-electric vehicles (called micro-hybrids,) fuel economy
Fuel economy in automobiles
Fuel usage in automobiles refers to the fuel efficiency relationship between distance traveled by an automobile and the amount of fuel consumed....
gains from this technology are typically in the range of 5 to 10 percent.
Since automobile accessories like air conditioners and water pumps have typically been designed to run off a serpentine belt
Serpentine belt
A serpentine belt, also known as a multi-vee, poly-v, or multi-rib belt, is a single, continuous belt used to drive multiple peripheral devices in an automotive engine, such as an alternator, power steering pump, water pump, A/C compressor, air pump, etc. The belt may also be guided by an idler...
on the engine, those systems must be redesigned to function properly when the engine is turned off. Typically, an electric motor is used to power these devices instead.
This technology has also been used on Honda Motor scooters in Asian markets for the last decade. Their PCX 125cc model was released in 2010 to be sold in Europe with this technology, though their North American model does not feature it.
Carmakers and models
Devices of this type have been tested since the mid-1970s, when the Toyota corporation fitted a Crown sedan with a electronic device that would automatically switch off the engine after sitting stationary for 1.5 seconds. Testing showed about a 10% improvement in fuel economy in Tokyo traffic.Some of the earliest production vehicles to use this technology were the Volkswagen Polo
Volkswagen Polo
The Volkswagen Polo is a supermini car manufactured by Volkswagen. It is sold in Europe and other markets worldwide in hatchback, saloon, coupé and estate variants....
"Formel E" and Fiat Regata
Fiat Regata
The Fiat Regata is the saloon version of the Fiat Ritmo small family car, produced by Italian automaker Fiat. It was produced from 1983 to 1990, corresponding to the post-facelift Ritmo. The Regata had a choice of three gasoline and two diesel engines...
"ES" models of the 1980s. The Volkswagen Group
Volkswagen Group
Volkswagen Group is a German multinational automobile manufacturing group. , Volkswagen was ranked as the world’s third largest motor vehicle manufacturer and Europe's largest....
also adopted it in the Golf
Volkswagen Golf
The Volkswagen Golf is a small family car manufactured by Volkswagen since 1974 and marketed worldwide across six generations, in various body configurations and under various nameplates – as the Volkswagen Rabbit in the United States and Canada , and as the Volkswagen Caribe in Mexico .The...
Ecomatic in 1994 and in the Volkswagen Lupo "3L" and the Audi A2 "3L" in 1999. Though these early implementations were considered rather disconcerting by many drivers, and high pricing failed to yield these cars much commercial success, both the Volkswagen Lupo and the Audi A2 (in their "3 litre" leverage) still hold the world record for most fuel efficient production car to date.
Citroën
Citroën
Citroën is a major French automobile manufacturer, part of the PSA Peugeot Citroën group.Founded in 1919 by French industrialist André-Gustave Citroën , Citroën was the first mass-production car company outside the USA and pioneered the modern concept of creating a sales and services network that...
introduced a more refined system in its C2
Citroën C2
The Citroën C2 is a supermini-class car produced by the French manufacturer Citroën since autumn of 2003, replacing the Citroën Saxo, it was built at the Aulnay plant on the outskirts of Paris. A different model, based on the Peugeot 206, is sold in China as the C2...
and C3
Citroën C3
The Citroën C3 is a supermini car equipped with a range of inline-four engines that has been produced by the French automaker Citroën since 2002. It was designed by Donato Coco and Jean-Pierre Ploué, previously known for designing the first generation Renault Twingo; the former has been the head of...
models by 2006, named "Stop and Start". The Citroën implementation combines a SensoDrive automated gearbox and an electronically controlled reversible alternator or integrated starter-generator (ISG). An ISG, also known as "integrated starter-alternator", combines the role of the starter
Automobile self starter
A starter motor is an electric motor for rotating an internal-combustion engine so as to initiate the engine's operation under its own power.- History :...
and alternator into one unit;
manufacturers include Valeo
Valeo
Valeo is a French automotive components manufacturer.-History:The Société Anonyme Française du Ferodo was founded in 1923 in Saint-Ouen, a suburb of Paris...
and Denso
DENSO
is a global automotive components manufacturer headquartered in the city of Kariya, Aichi Prefecture, Japan. Established December 16, 1949 as , in 1996 the company became DENSO Corporation worldwide...
.
BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...
is including the technology across many of its cars and the MINI
MINI (BMW)
Mini is a British automotive marque owned by BMW which specialises in small cars.Mini originated as a specific vehicle, a small car originally known as the Morris Mini-Minor and the Austin Seven, launched by the British Motor Corporation in 1959, and developed into a brand encompassing a range of...
line for 2008 as part of its Efficient Dynamics brand. BMW has been interested in ways to reduce parasitic loss
Parasitic loss
Parasitic loss is that which a parasite consumes from its host, for whom the loss may or may not be beneficial.- Parasitic loss in internal combustion engines :...
es on engines, so the company took the technology a step further. Instead of using an integrated starter generator, BMW has used an enhanced-starter which is nothing more than a conventional starter, developed by Robert Bosch GmbH
Robert Bosch GmbH
Robert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
, that can withstand the increased number of engine-starts in a stop-start vehicle. BMW has developed the system such that the alternator is not activated most of the time. This means that electrical components in the vehicle are normally running on battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
power. When the battery needs to be charged or when decelerating or braking, the alternator is activated to recharge the battery (regenerative braking). Since this battery experiences very different load characteristics than a normal car battery, BMW used an absorptive glass mat type instead. Due to the use of regenerative braking, some have started calling this type of system a micro hybrid, a step below a mild hybrid
Mild Hybrid
Mild hybrids are essentially conventional fossil-fuel vehicles equipped with a large electric machine allowing the engine to be turned off whenever the car is coasting, braking, or stopped, yet restart quickly...
system where the ISG can be used to assist the engine or even drive the vehicle.
Toyota has been selling cars with start-stop system for several years in Japan. Both Toyota and Mazda
Mazda
is a Japanese automotive manufacturer based in Fuchū, Aki District, Hiroshima Prefecture, Japan.In 2007, Mazda produced almost 1.3 million vehicles for global sales...
will be introducing stop-start technology available also outside of Japan in some of their 2009 model year vehicles, and Renault will introduce the technology in all of its European models by 2010.
The i-Stop system, Mazda
Mazda
is a Japanese automotive manufacturer based in Fuchū, Aki District, Hiroshima Prefecture, Japan.In 2007, Mazda produced almost 1.3 million vehicles for global sales...
’s first start stop system, detects which piston is in the best position to restart quickest, which is the one in the combustion stroke phase, where air and fuel are in the cylinder, ready to be ignited. The mixture in this cylinder is ignited by the spark plug, forcing that piston down, resulting in a near instantaneous engine start time of 0.35 seconds.
In 2011, Mazda has announced i-ELOOP, a system which uses a variable-voltage alternator
Alternator
An alternator is an electromechanical device that converts mechanical energy to electrical energy in the form of alternating current.Most alternators use a rotating magnetic field but linear alternators are occasionally used...
to convert kinetic energy to electric power during deceleration. The energy stored in a double-layer capacitor, is used to supply power needed by vehicle electrical systems. When used in conjunction with Mazda’s start-stop system, i-Stop, the company claims fuel savings of up to 10%.
Honda
Honda
is a Japanese public multinational corporation primarily known as a manufacturer of automobiles and motorcycles.Honda has been the world's largest motorcycle manufacturer since 1959, as well as the world's largest manufacturer of internal combustion engines measured by volume, producing more than...
has been using this technology for over a decade. This was seen on the first gen Insight models sold in the Japanese domestic market (JDM) since 1999.
Fiat introduced the Robert Bosch GmbH made system in the end of 2008 in Fiat 500
Fiat Nuova 500
The Fiat 500 or Fiat Nuova 500 is a city car built by Italian automaker Fiat since 2007. The car is currently produced in Tychy, Poland by Fiat Auto Poland S.A. and in Toluca, Mexico, by Chrysler Group LLC. The four-seater, three-door hatchback 500 is almost identical to the retro concept car...
, while Volvo introduced it in 2009 in its DRIVe models.
Starting September 2009, Alfa Romeo
Alfa Romeo
Alfa Romeo Automobiles S.p.A. is an Italian manufacturer of cars. Founded as A.L.F.A. on June 24, 1910, in Milan, the company has been involved in car racing since 1911, and has a reputation for building expensive sports cars...
also introduced this system in its Alfa Romeo Mito
Alfa Romeo MiTo
The Alfa Romeo MiTo is a three door sporty supermini officially introduced on June 19, 2008, at Castello Sforzesco in Milan, with an international introduction at the British Motor Show in 2008. The car was available in all Alfa's major markets in stages from July...
series utilising Fiat Powertrain Technologies' (FPT) 1.4 L Turbo petrol MultiAir engines.
Mahindra's were the first in India to launch Stop Start based Micro Hybrid system. This involves home-grown technology and first of its kind component development like Hall sensor based neutral and clutch pedal sensors. Mahindra & Mahindra introduced the stop start based Micro Hybrid system to Indian Automotive market. This involved home grown technology for vehicles with mechanical fuel injection and later JV with BOSCH for common rail based vehicles.
Tata Motors has later introduced this system on their LCV Tata Ace
Tata Ace
The Tata Ace is a mini-truck launched in May 2005 by Tata Motors in India. It is in competition with the prevalent three-wheeled goods carriers from Bajaj Auto, Piaggio, Mahindra and Force Motors.-History:...
.
Late in 2010, Ford announced that its start-stop system, already used in its hybrids as well as several mainstream models in Europe, would be introduced in North America with the 2012 models, initially with 4-cylinder engines and later proliferating into V6s and V8s. Eventually the system will be available in all Ford vehicles.
The redesigned 2012 Kia Rio and Rio5 (hatchback) debuted at the 2011 New York Auto Show was announced with their Idle Stop and Go (ISG) feature, or stop-start technology. Kia claims the combination of direct fuel injection and stop-start will offer 30MPG City/40MPG on the highway in both 6 speed manual and automatic transmissions. While both the Kia Rio and Rio5 share the same new direct-injected four-cylinder 1.6L engine with it's cousin Hyundai Accent/Verna (also newly redesigned for 2012), Hyundai made no mention of this feature in their Accent line.
Concerns
The National Highway Traffic Safety Administration (NHTSA) in the US raised questions about non-hybrid Honda vehicles equipped with the company's 'Idle Stop' transmissions in February 2001 due to concerns over the "sudden lurching forward of a vehicle in an automatic restart" – rather than the "gradual creeping forward found in current transmission designs."Hybrid/electric assist vehicles experience almost no delay in power from a stop, due to the instant availability of power from the traction battery to the electric motor(s). Gasoline/microhybrids on the other hand generally experience slight delays (albeit fractions of a sec).
Many people think that long term use may wear the components in Start-Stop implementations which require a starter motor, but this is not true. Mazda
Mazda
is a Japanese automotive manufacturer based in Fuchū, Aki District, Hiroshima Prefecture, Japan.In 2007, Mazda produced almost 1.3 million vehicles for global sales...
i-stop used in their Mazda3/Axela line (in Europe and JDM) uses combustion to restart their engine by sensing the position of the piston in the cylinder. They claim quieter and quicker engine restart within 0.35 seconds.