What happens to all the heat generated by cars, trucks and industrial plants?

Answer 1

That is an interesting question. It just goes into the surroundings. Compared to the amount of energy delivered by the sun everyday it is a very tiny amount of energy so it has almost no impact. The sun delivers about the same amount of energy in 45 minutes that the entire human race uses in one year.

There are a few exceptions where local impacts are important. Some power plants use river water for cooling and they can heat up a river enough to have impacts on fish in the river for one example.

The total energy from the Sun that hits the Earth in one hour is about 6,200 quatrillion J.

The total energy consumed by the world in one year (2001) is about 4,260 quatrillion J.

The very considerable amount of energy delivered by the sun is the reason that solar energy is the alternative energy source of choice for the long term. I like to think of it as wireless nuclear power.

Answer 2

Global Warming

Answer 3

It ends up in a giant heat sink called the atmosphere. Everything humans do creates heat - transportation, industries, homes, recreation, even refrigeration. It all ends up in the atmosphere and contributes to global warming.