MIT Sees the Light: Eliminate Alternators

mit sees the light eliminate alternators

Car engines generate plenty of heat. According to Technology Review, researchers at MIT have a bright idea: use “thermophotovoltaics” to convert heat into light, then convert the light into electricity. The prototype system uses gasoline to heat tungsten to illuminate a photovoltaic cell to generate electricity. The hope is that systems based on this research could eventually replace the current gas-wasting alternators and air conditioning compressors. Of course, this technology hasn’t escaped the attention of the Department of Defence. "The military has had a lot of interest in it for portable power supplies in the field. Because there are no moving parts, there wouldn't be any noise, so you couldn't detect it," says NASA researcher Donald Chubb. It’ll be a few years before we see any practical applications, but as one of the key research sponsors, Toyota would be the first automaker in line.

Comments
Join the conversation
4 of 13 comments
  • NeonCat93 NeonCat93 on Aug 17, 2007

    I know it is probably a dumb, inefficient idea, but could you mount a small Stirling cycle engine on the exhaust manifold and use it to generate electricity? What about a small turbine in the exhaust flow? Would it create too much back pressure for the engine?

  • Akitadog Akitadog on Aug 17, 2007

    I appreciate MIT's research into these types of projects, but really, this reminds me of NASA's project to make a space pen. Seems some people make things harder than they need to be. Along the same lines of NeonCat93's thinking,I was thinking add a turbine in the exhaust that spins a magnet inside a coil. Instant free electricity. Low-tech, but proven concept and low maintenance. Or is that too easy?

  • Miked Miked on Aug 17, 2007
    I know it is probably a dumb, inefficient idea, but could you mount a small Stirling cycle engine on the exhaust manifold and use it to generate electricity? Just like shaker's idea and bolhuijo's responce, for a Stirling engine (or any engine) to work, you need to have a hot side and a cold side. In an IC engine, the hot side is the explosion the pushed the piston down, and the cold side is the exhaust. What you're trying to do is use the exhaust as your hot side and the atmosphere as your cold side. There's just not much of a temperature difference there to actually get any useful work. Along the same lines of NeonCat93’s thinking,I was thinking add a turbine in the exhaust that spins a magnet inside a coil. Instant free electricity. It ain't free. That would increase back pressure which would make the engine work harder. You never get anything for free. Even taking heat out of the exhaust to run a Stirling engine would not be free. The fact that the exhaust gasses are hot makes them flow easier and have less back pressure, cooling the gasses would put more strain on the motor. One thing people don't realize is that (most) engineers and scientists are actually pretty smart and have thought of most of these ideas. The reason that many of the ideas are not in place is because they don't actually help. Believe me, especially with such high gas prices, if any car company could instantly increase efficiency with "simple" ideas, you better bet they'd be doing it. These problems are actually quite hard, that's why it takes teams of smart people to solve them.

  • Fallout11 Fallout11 on Aug 20, 2007

    Beautifully said, miked. "There is no free lunch." - Robert Heinlein

Next