July 09: By cleverly combining an internal combustion engine with something
similar to a steam engine, BMW have given us a new type of hybrid. The new
technology is called a
turbosteamer and could herald a
further jump in
fuel efficient vehicles. Internal combustion
engines by their nature get very hot and emit hot gases. All this heat is
wasted energy and is not used (apart from keeping you warm in winter!).
If this heat energy could be recaptured and reused it would make the whole
process a lot more fuel efficient. This is exactly what the turbosteamer
does.
The boffins at BMW think they can reduce heat energy loss by as much as
80 per cent through this technology. Obviously they won't tell us too much
about how a turbosteamer works but they do say it uses engine exhaust gases
to heat fluid stored in a heat exchanger. The heated fluid becomes so hot
it turns into steam. This steam is then able to turn the engine's crankshaft
through the use of expansion units attached to the crankshaft.
BMW tested a prototype turbosteamer on a 3-series with a 1.8 litre engine.
They improved the vehicle's fuel economy by approximately 15 per cent. An
added bonus of the technology was an extra 14 horsepower for the 3-series
engine.
Turbosteamers can be fitted to all types of vehicle and certainly all those
in the BMW fleet. However... not yet. This technology has much work still
to be done to make it commercially viable. At its present size there's only
space for the turbosteamer in the engine bay of BMW's 1.8 litre four cylinder
engine. BMW need to make the turbosteamer's parts smaller. They additionally
need to make the turbosteamer simpler and cheaper. Don't expect this technology
to hit the market any time soon. BMW say they hope to have fuel-efficient
vehicles for sale fitted with turbosteamers in around 10 years time. Lets
hope they manage to get it out quicker than that.