Ah, you mean an ICE gasoline engine adds more heat to the atmosphere than an electric car. Yes, because it uses more primary energy. Even if the electric car is powered by an inefficient coal plant, it still uses less energy and produces less CO2 than gasoline. Nowadays most electricity comes from natural gas, wind, nukes or solar.
The heat added by combustion (or a nuclear plant) causes heat island problems, and it heats up rivers, but it does not cause much damage. It leaves the earth in about a half hour. It is not the cause of global warming. That's CO2.
Hybrid cars are much more efficient than ordinary ICE cars. They were a good solution around 2000. But I think they are rapidly becoming obsolete. Fully electric cars will replace them, once the range is long enough and the price falls. I think that is why Toyota has decided to license its patents for free. They want to sell parts to other companies, and they think the window for such sales will close soon. That's what I read.
The final generation of ICE cars is here, and it is the most efficient and probably the best quality in the 130 year history of that technology. It often happens that a technology improves rapidly just before it goes extinct, because it is competing with the new technology which will soon replace it. For example, the last generation of sailing ships, around 1900, were mainly schooners, because you can raise and lower the sails from the deck with machinery. They required fewer sailors, and the sailors were safer. By 1900, not many people were willing to climb up masts to set square sails. The hybrid automobile "borrows" battery and motor technology from the electric car which will soon replace it. The last generation of large propeller driven passenger airplanes were mainly turboprops (prop-jets), with a jet engine turning a large propeller, like the Lockheed Electra. This was a sort of intermediate technology, after jet engines were invented but before they were ready for large passenger planes.
A bicycle is the most efficient means of transportation per passenger mile. A person walks at about 3 mph. When you pedal a bicycle with about the same exertion as walking, you go 6 or 8 mph. An electric bicycle is even more efficient because the conversion from fossil fuel => electricity => vehicle propulsion has better Carnot efficiency than human metabolism. Granted, fossil fuel is not renewable, whereas food is.
