Solar energy and thermal pollution

A previous post in this blog stated that if 100% of the energy used by man came from solar energy, the Earth would warm up, and although air pollution and the greenhouse effect would decrease, there would still be thermal pollution. Can we give figures? By how much would the Earth's temperature rise in that case?

According to various sources ([1] and [2]), world power consumption by humans is currently about 18.5 Terawatts (18.5 trillion watts). To find the energy consumed during a given period of time, we should just multiply this figure by the given time. For example, the total energy expenditure during a non-leap year, expressed in Terawatt-hours, will be found by multiplying 18.5 by 365 and by 24 (the number of hours in a year), which is equal to about 162,000 Terawatts-hour.

Is solar energy clean?

For decades we have been sold the idea that when we fully harness solar energy, all our problems of getting cheap and abundant energy, air pollution, and global warming will be solved.

For decades I have been warning that this optimistic approach is not true. If we were able to completely replace energy from fossil fuels (coal, oil and natural gas) by solar energy, some of our problems will not go away, they will just take longer to become unsustainable, especially the problem of global warming.

Why do I think this? Because the Earth receives a certain amount of solar energy. A part is used by plants to carry out the chlorophyll function, which transforms inorganic matter into organic matter, thus making life possible for all animals, including us, humans. Another part heats the oceans and the continents, allowing the Earth to maintain an almost constant temperature, despite the heat losses it suffers every day from the side opposite the sun. Finally, another part of the solar energy is reflected or diverted, in the atmosphere or on the surface, and is lost in outer space.