[clairity]

it's not even that surprising when you consider that basically all of earth's energy through its lifetime derives from the sun in some form.

the main exceptions--radiative exchange with the rest of the universe and energy from earth's core--are relatively insignificant sources compared to the solar influx of energy.

fossil fuels are just solar energy captured and (inefficiently) transformed over hundreds of millions of years through plant and animal intermediaries. wind and hydro (weather-based energy) are also intermediated forms of solar energy.

the sun is effectively unlimited energy for billions of years, mostly being radiated away right now, so the closer we get to transforming it directly into useful forms, the better off we are.