Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electricity from the exhaust pipe

04.06.2008
Researchers are working on a thermoelectric generator that converts the heat from car exhaust fumes into electricity. The module feeds the energy into the car’s electronic systems. This cuts fuel consumption and helps reduce the CO2 emissions from motor vehicles.

In an age of dwindling natural resources, energy-saving is the order of the day. However, many technical processes use less than one-third of the energy they employ. This is particularly true of automobiles, where two-thirds of the fuel is emitted unused in the form of heat.

About 30 percent is lost through the engine block, and a further 30 to 35 percent as exhaust fumes. Scientists all over the world are developing ways of harnessing the unused waste heat from cars, machines and power stations, in order to lower their fuel consumption.

There is clearly a great need for thermoelectric generators, or TEGs for short. These devices convert heat into electrical energy by making use of a temperature gradient. The greater the temperature difference, the more current TEGs can produce. Researchers at the Fraunhofer Institute for Physical Measurement Techniques IPM are developing thermoelectric materials, modules and systems to harness the residual heat in automobiles.

“The temperatures in the exhaust pipe can reach 700 degrees Celsius or more,” says Dr. Harald Böttner, head of the Thermoelectric Systems department. “The temperature difference between the exhaust pipe and a pipe carrying engine cooling fluid can thus be several hundred degrees Celsius.” The thermoelectric converter makes use of this huge differential: Driven by the flow of heat between the hot exhaust fumes and the cold side of a coolant pipe, the charge carriers pass through special semiconductors, thus producing an electric current similar to a batterie.

The long-term objective is to make the alternator superfluous and to supply energy to the constantly rising number of power consumers in the car. TEGs could cover a significant proportion of a car’s power requirements: “This would make it possible to cut gas consumption by between five and seven percent,” says Böttner.

A simple calculation will illustrate how important it is to increase the energy efficiency of cars: There are about 50 million licensed motor vehicles in Germany, each of which is – as a basis for an estimation – on the road for an average of 200 hours a year.

If their waste heat was utilized by TEGs during that time, with an output of one kilowatt sufficient to power parts of vehicle electronics, this would add up to ten terawatt hours of energy per annum – a significant contribution. The researchers are still in the experimentation phase at present, but they plan to build the first prototypes very soon.

Press Office | alfa
Further information:
http://www.fraunhofer.de/EN

More articles from Power and Electrical Engineering:

nachricht The world's most powerful acoustic tractor beam could pave the way for levitating humans
22.01.2018 | University of Bristol

nachricht Siberian scientists learned how to reduce harmful emissions from HPPs
22.01.2018 | Siberian Federal University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Optical Nanoscope Allows Imaging of Quantum Dots

Physicists have developed a technique based on optical microscopy that can be used to create images of atoms on the nanoscale. In particular, the new method allows the imaging of quantum dots in a semiconductor chip. Together with colleagues from the University of Bochum, scientists from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute reported the findings in the journal Nature Photonics.

Microscopes allow us to see structures that are otherwise invisible to the human eye. However, conventional optical microscopes cannot be used to image...

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Rutgers scientists discover 'Legos of life'

23.01.2018 | Life Sciences

Seabed mining could destroy ecosystems

23.01.2018 | Earth Sciences

Transportable laser

23.01.2018 | Physics and Astronomy

VideoLinks Science & Research
Overview of more VideoLinks >>>