At highway speeds yes, in city driving no.
Window units are more efficient than Split-Acs. Not the other way round.
Brands that make cellular shades are more energy efficient window blinds.
You can only get gas heating and air conditioning. The gas heating and air conditioning is less because it uses less gas then how much water you would be using. The electricity for the heater and AC can be fairly cheep.
Window fans are cheaper to run electricity wise in the summer. Air conditioning will cost more but it's much more effective if it's really hot.
The engine was cleaner and more efficient.
Access window
Window air conditioner units are cheap to put in but not so efficient. There are some very good Energy Star efficient window air conditioners but they cost more to install.
Depends on where you live. If you live far enough north, you won't use the a/ c enough for a more efficient central air system to pay off the investment. In general window and casement units are the lowest efficiency, then the split systems, and the central a/c systems are the most efficient. All but the central air let you cool only the rooms you are using, so there is a potential savings if you are only using a few rooms in a large house.
Generally speaking vinyl windows will be more energy efficient than other window typs Make sure you choose a quality vinyl window,it ill help with your energy cost.
Gas central heating is more efficient than electric.Open cast mining can be more efficient than deep mines.
Putting new windows in the home will not make the house more energy efficient. There would have to be a specific type of glass in the window.
No, it is less fuel efficient.