At the most basic level, our car engines produce power through thermal expansion. The greater the difference in heat, the more power we are able to produce. However, extremely cold temperatures can also increase fuel consumption and tailpipe emissions. Knowing this, BMW has begun a series of tests to try and reduce both by keeping the engine warm even after being turned off.
The idea is based on research that has shown just how much of an effect cold temperatures have on fuel efficiency. According to these studies, every degree Celsius the engine is above the outside ambient temperature increases fuel economy by about 0.2%.
To combat this, BMW is planning on encapsulating the engine and many of the engines components in an insulated shell made of the same components typically used to insulate a vehicles floor. In doing so, it will allow the powerplant to heat up much more quickly as well as sustain its temperature longer. Initial testing has shown that the insulated shell is able to keep the temperature of the engine up around 104 degrees Fahrenheit after 12 hours of not being run.
This would not only help to reduce the amount of fuel consumed during cold starts, but cut back tailpipe emissions during cold starts as well.
Testing is expected to continue through next year.Motor Authority