Humans and the animal kingdom in general eat food for energy. You may choose to get that energy by eating say a T-bone steak with a side salad. The steak came from a mammal that got its energy from grass, which got its energy from the sun through the miracle of photosynthesis. Same goes for the salad.
We drive to work in an automobile, which of course needs gasoline. Gasoline is a petroleum product that was formerly massive amounts of dead plants and animals that through geological processes decomposed into underground pools of oil. As mentioned plants got their energy to grow from the sun, and therefore oil is merely stored solar energy.
Flip on a light switch. The illuminated bulb gets its energy from a power plant that uses steam generators powered by burning coal. Coal is another fossil fuel that started out as living plants that used the sun for energy. So again coal is merely stored solar energy. If your light bulb gets its electricity from a hydroelectric power plant, it’s still solar produced. The water held back by the dam started out at the ocean, where sun heating evaporates some of the water, which floats up into the atmosphere. The water vapor may travel from the Gulf of Mexico, across Texas and Louisiana, and finally over Tennessee, where it falls as rain. Some of that rain enters a stream that carries it to Powell or Clinch River, and ends up in Norris Lake, where some of it pushes through a concrete pipe to turn a turbine that powers your home. Again, the origin is the sun.
Natural gas, firewood, every energy source I can think of ultimately comes from the sun, except two: nuclear and geothermal. It strikes me that since nature uses solar power perhaps we should follow suit and use it more directly than we presently are. Burning fossil fuels tends to cause a lot of problems that converting sunlight directly into electricity would solve. Solar heated homes are getting to be more common, and ought to be given serious consideration by homebuyers.