With oecumenical reserves of fossil fuel gradually diminishing and air pollution increase , automotive engineers are constantly on the lookout for way to make cars more fuel effective and to reduce their carbon emissions . One of the most surprising places they ’ve get wasted energy is in the railroad car ’s exhaust . Actually , automotive designer have been tapping the hidden power of automobile fumes since the early 1970s . Because this technology recycles the fumes before it can pop off the vehicle , it also helps trim the emanation produced by a car and assist fight melodic phrase defilement .
technology made to maximize the efficiency of a vehicle ’s exhaust are known collectively asexhaust heating plant recovery and recirculation . There are several ways to apply a fomite ’s fumes to increase its fuel efficiency and make it draw with few emanation . For example , the heat of the car ’s exhaust can be used to warm the engine coolant to keep the locomotive melt warm , even when the motor has been turned off for a pregnant length of time . The interior of the car can also be warm using exhaust heat , even in very cold weather . The amount of nitrous oxide ( N2O ) emissions can be reduced , and a fomite ’s exhaust can actually be used to get electricity . The termexhaust heat recoveryis used for the procedure by which the fumes ’s heat energy is recycled through both the car and the locomotive engine , so it ’s a part of all of these technologies .
Although these technology can be used in any car , truck or SUV with an national burning engine , they ’re especially authoritative to hybrid vehicles , which need to bring on maximum fuel efficiency and minimum discharge . Some of the most advanced carrying out of this engineering can be find in the 2010 Toyota Prius . In the next few pages , we ’ll look at how self-propelled engineer have made this engineering possible .
Nitrous Oxide Emissions
The internal combustion engine in cars , trucks and other vehicles bring forth several kinds of defilement . One of the most common is C dioxide emissions , which play a meaning function in global warming . cut back carbon emissions has become one of the most important goals facing self-propelling engineers . However , car engine produce other emission as well . One of the major components of smogginess is N2O –nitrous oxide– and these emission are also bring forth by inner combustion engines .
Like carbon dioxide , nitric oxide is agreenhouse gasoline . This means that it ensnare the heat in solar radiation – sun – within our aura and uses it to heat the Earth ’s surface . Without the heating system trapped by greenhouse gases , the Earth’s surface of the earth would be too insensate to abide lifetime . However , the good Libra the Balance is important . While too little would rick the terra firma into a frozen snowball , too much would turn it into a sweltering jungle or desert . Human beingness and our engineering have evolved to require a certain clime . Anything that change that mood may affect the way we live , dramatically altering agrarian radiation pattern and melt down the polar icecaps .
It ’s clear that reducing nitric oxide emissions from cars is just as important as reducing atomic number 6 emission , but how can the emissions be reduced ? Nitrous oxide is produced at very high temperature , so anything that glower the operating temperature of an internal combustion locomotive would cut N2O emissions . That ’s where fumes heat recirculation comes in . We ’ll speak about this in more point on the next page .
Exhaust Heat Recirculation
The key to tire heat recirculation is a machine called anexhaust gasolene recirculation(EGR ) valve . The EGR valve opens when it encounters back pressure from the car ’s exhaust and channels it back into the burning chamber . You might wonder what good this does , since the strain in the bedchamber is assorted with gasolene to make it combustible . Well , one thing it does is to make the fuel warmer . Warm fuel heats up more efficiently and therefore produces more nautical mile per gallon . Once the EGR valve senses that the engine is warm enough , it redirect the exhaust elsewhere to forestall the engine from overheat .
Warming the coolant and the fuel not only helps the engine attain its optimal temperature faster when the railway locomotive is first started , but it also has a specific welfare for loanblend . Most hybrid are contrive so that the inner combustion engine turns off when the fomite is stopped . If it remains off for too long , the engine can get cold . EGR help keep the locomotive engine from cooling down too quickly .
How does exhaust gas recirculation reduce pollution ? The emissions direct by EGR hail from nitrous oxide that are produced at very high temperature . By mixing the machine ’s exhaust with the intake aura , the amount of atomic number 8 in the mixture is reduced and its combustibility is also decreased , which causes the fuel to burn at a lower temperature . In most EGR arrangement , the exhaust is also cooled before it ’s mixed with the gas . Therefore , fuel merge with exhaust burns cooler and less likely to bring forth N2O. The low temperatures also aid fuel economy . With fuel less prone to detonation , the programmers who compose the software package timing subprogram for modern engine have more control over the precision of the engine ’s timing . The lower temperature also serve to debar estrus conveyance vitality losses , meaning that more of the car ’s energy goes into providing power for its wheel .
As we ’ve seen , recirculating exhaust can both increase fuel efficiency and reduce pollution . But did you jazz that it may also be able-bodied to acquire electrical energy ? We ’ll research that concept on the next page .
Electricity from Exhaust
thermoelectrical material , as the name implies , can produce heat from electrical energy . These material were discovered in 1821 by the German physicist Thomas Seebeck . They ’ve generally been too expensive and inefficient to be of any use to self-propelled engineers , but this has started to change : The U.S. Department of Energy has expressed pursuit in funding the maturation of a virtual thermoelectric organisation that could be used in elevator car .
There are many sources of wasted heat in cars , including the radiator and the engine , but the gravid source is belike the exhaust system . Given that most elevator car already recirculate exhaust in an EGR loop and that this technology will be even more important in the time to come , this provides an idealistic opportunity to ensnare this otherwise wasted hotness and utilise thermoelectric devices to commute it into electrical energy . This electrical energy could be used to power the machine ’s electrical systems , reload the assault and battery , and perhaps most importantly , launch the electric motor in hybrid andplug - in batteryelectric vehicle . This would be a nearly unadulterated meeting of several engineering , and would have the side effect of helping to deoxidize azotic oxide emissions by further cooling the exhaust fumes before it ’s mixed with fuel .
Any type of automobile could benefit from this thermoelectric boost , but once again , it would be most useful when applied to hybrid vehicles . It would extend their reach by supplementing thebatteriesthat start the electric motor and reduce the amount of time ask to reload those batteries .
The development of fuel - efficient and humbled pollution technology like exhaust fumes recirculation and thermoelectric power will make the elevator car of the future – which will have slight or no utilisation for fossil fuel – potential . It ’s significant that we develop these technologies now , before fossil fuels move out and befoulment does significant damage to the Earth ’s atmosphere and climate .
