Pete C. wrote:

Rather similar to hybrid
cars getting lousy MPG in areas with high speed roads and little stop
and go traffic, the savings opportunities just don't exist.

The only hybrid I have read very detailed info on is the Prius. The EPA
mileage is 48 city, 45 highway (EPA gives an idea what mileage is like).
Consumer Reports *tests* had a higher highway mileage than city with
44mpg overall. (That is for the old Prius - there is a new 2010 model
out - haven't seen much info except mileage is higher.)

The Prius does not get "lousy" highway mileage.

The Prius gets high highway mileage because:
- I has a relatively small engine. You don't need high end power often
and when it is needed both the gas engine and electric motors are used.
The engine operates in a more efficient band.
- The gas engine is a more efficient Atkinson cycle - the intake valves
stay open part of the compression stroke making the compression stroke,
in effect, shorter than the power stroke. More of the energy is captured
on the power stroke. The engine can change the valve timing. I have not
seen it explained, but I believe the engine shifts toward a conventional
engine when high power is needed.

A Ford Fusion hybrid coming out has the features above - haven't seen
details.

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bud--