The heat from the exhaust pipe is a waste of energy. Now, however, researchers have found a way to use that energy. Namely as electricity for the battery.
When it comes to harnessing the energy in gasoline or diesel, the internal combustion engine is in many ways a hopeless invention. Up to 60 percent of the energy disappears in the exhaust as pure heat.
But now a team of American researchers has developed a method that can convert some of the heat from the exhaust pipe into electricity, which can be used to charge a battery.
This is stated in a scientific article published in ACS Publications .
It is well known that the internal combustion engine is not very efficient. A large part of the energy in the fuel is converted into waste heat instead of propulsion.
Not everything is wasted. Some of the heat is used to heat the cabin, but most of it disappears through the exhaust pipe.
American researchers have developed a technique that can utilize this waste heat from the exhaust. They have placed a cylindrical carbon fin around the exhaust pipe. The carbon fin collects the heat and converts it into electricity.
The process is carried out using a thermoelectric generator. The generator exploits the temperature difference between the hot exhaust gases and the colder air around the exhaust pipe to produce electricity.
In experiments, the researchers have managed to generate 40 watts. In computer simulations, they reached as much as 56 watts with a regular car engine and a whopping 146 watts with a helicopter engine.
Although researchers have succeeded in converting waste heat from emissions into electricity, there are still challenges. The amount of electricity generated is not sufficient to charge a high-voltage battery in an electric car.
In a regular car with an internal combustion engine, however, the system can help relieve the load on the generator and thus reduce the car's fuel consumption. It can also be exchanged for fewer harmful substances from the exhaust pipe.
However, the researchers do not deny that the system can be improved. That is, become more efficient. In fact, they are continuing to work on improving the technology so that it can play a greater role in the cars of the future.
Even small improvements in fuel efficiency can have a significant impact on overall fuel consumption and thus also on the emission of harmful substances from exhaust.
This new method of utilizing waste heat from exhaust is a step in the right direction. However, it is important to remember that there is still some way to go before the technology is efficient enough to be used in electric cars.
Until then, it may be a relevant solution to reduce fuel consumption and emissions in cars with internal combustion engines.
The Chinese, despite a greater focus on electric cars, are actually quite far along in this regard. In April 2024, a team of Chinese researchers was able to demonstrate a diesel engine that utilizes 53.09 percent of the energy.
Even the German TUV had to admit that no other combustion engine for passenger cars has managed to do that. Read more about the engine here.
