"John Williamson" wrote in message
...
Doctor Drivel wrote:
John Williamson wrote:
Doctor Drivel wrote:

"Dave Plowman (News)" wrote in message
...
In article ,
tony sayer wrote:
The same reason we will have highly inefficient piston engines.
Corporations run matters.


What corporations and why then?..

More conspiracy theory. Dribble wants to replace a highly
inefficient piston engine

This proves this person senile. Piston engines are approx 20%
efficient. 80% of the energy in the tank is wasted.

The US government say 30% for petrol, 45% for diesel.

Running constantly at optimum conditions. In real world driving 20% for
petrol and a little more for the soot emitting crap engines. Diesels are
a waste of time in vehicles. Heavy and dirty and more complex than petrol
engines. Petrol engines in hybrid buses are far better and also in
hybrid trucks.

Some large, low speed, turbocharged two stroke diesels manage over 50%.

http://www1.eere.energy.gov/vehicles...sel_engine.pdf

My God! It says 45 percent and "further advances are possible". The 45%
is a static constant peed job like in a ship or generator.

Slow speed marine diesels have been doing slightly better than 50% since
the 1950s.

Thank you. The average is 20% to 25% in road use.