There are two basic uses of solar energy - heat and generating electricity. Sunlight is captured and converted into either usable heat or usable electrical power. Light is composed of individual photons, each with a wavelength and an energy, and all travelling at the same velocity.
During World War II, the United States launched the Manhattan project, which produced the first atomic bombs. With technological advancements based on this fundamental research, in December 1942 the first nuclear reactor was tested in an abandoned handball court at the University of Chicago. This test proved the viability of large scale nuclear power reactors for utility scale use.
Under huge pressures and amidst the Earth’s core heat, decayed and decaying organic materials formed complex compounds primarily composed of hydrogen and carbon atoms. These complex, carbon-based compounds are more commonly referred to as fossil fuels. The three most commonly available fossil fuels are coal, petroleum, and natural gas.
Energy is a critical component of your lives and economy as a whole. You use energy in virtually every endeavor. Humans have evolved in step with the energy consumption. Human populations, quality of life, and life expectancy have increased as energy sources have become more sophisticated.