They are more environmentally-friendly than traditional internal combustion engine vehicles because they generally provide greater fuel economy
A gas-electric hybrid engine is a combination of a gasoline/petrol or diesel internal combustion engine with an electric motor to power a vehicle. Various designs exist for how the motor and engine interact with the drive train. Because the engine recharges the battery smaller batteries are required than in an electric vehicle.
A standard combustion engine is required to operate over a range of speed and power, yet its highest efficiency is in a narrow range of operation. Also, an engine designed for a reduced operating range can be more efficient than a standard engine. The battery storage and electric motor allows the engine to operate at its point of maximum efficiency, to be of a higher efficiency design, and to be smaller than non-hybrid applications.
The gas-electric hybrid uses less gasoline than conventional internal combustion engines and does not have the limitations in range that have been a problem for traditional electric vehicles. This type of piston engine is used in hybrid electric vehicles which have begun to enter the market as of 2002.
Insurance Tips:
Get quotes from different types of insurance companies. Some sell through their own agents. These agencies have the same name as the insurance company. Some sell through independent agents who offer policies from several insurance companies. Others do not use agents. They sell directly to consumers over the phone or via the Internet.
Many insurers will give you a break if you buy two or more types of insurance. You may also get a reduction if you have more than one vehicle insured with the same company. Some insurers reduce the rates for long-time customers. But it still makes sense to shop around. You may save money buying from different insurance companies, compared with a multi-policy discount.
Some companies offer reductions to drivers who get insurance through a group plan from their employers, through professional, business and alumni groups, or other associations. Ask your employer and inquire with groups or clubs you are a member of to see if this is possible.
PBS is looking for input from its audience for an upcoming Nova episode called 
Under the current federal 
