Almost all of the energy we use in our everyday lives ultimately comes from the Sun: the energy from the food we eat, the electricity powering our homes and workplaces, and the fuel used by the vehicles we use to move around.
Most of this energy comes from ancient sunlight. Unfortunately, we have now come to realize that harnessing ancient sunlight creates threats to our civilization’s continued existence. The secret to our survival on this planet lies in our ability to live to shift away from ancient sunlight, and to power our civilization using mostly recently sunlight.
Allow me to expound.
There are two main sources of energy that power things here on Earth. The first is the energy coming from deep inside the Earth: the heat of the Earth’s core. This energy can do things that are both slow and sudden. On the side of the slow, the energy from the Earth’s core moves continents and raises mountains. On the side of the sudden, this energy leads to earthquakes and volcanic eruptions.
The second main source of energy is the Sun.
There are many things that are obviously powered by the Sun. For example, we learned from grade school that all the energy in the food chain came from the Sun. Plants convert sunlight (light and heat energy) to food (chemical energy), which then goes up the food chain until it reaches our tables and mouths.
There is also the water cycle, the process by which the Sun moves water around the face of the Earth. It supplies the heat that evaporates water. The water vapor forms clouds and rains down, usually somewhere else.
But there are many other things that derive their energy from the Sun. For example, the wind gets its energy from the Sun. The Sun heats up different parts of the Earth’s atmosphere in different ways. This results in differences in the air pressure, which makes the wind blow.
In fact, our civilization is almost entirely powered by energy from the Sun, from the generation of electricity to the fuels we use to power our vehicles. The only exceptions would be the geothermal energy (it comes from deep inside the Earth) and nuclear (which comes from the energy of splitting atoms).
By now the astute reader would be saying hold on, are we not mostly powered by fossil fuels? Are not most of the electricity we use generated using coal, oil, ang gas? And are not almost all vehicles out there running, floating, or flying powered by oil?
Well, yes. But all these fossil fuels—coal, oil, and gas—ultimately derive their energy from the Sun.
Fossil fuels are, as the name suggests, fossils. They are the remains of organisms that lived on Earth millions of years ago.
For example, coal, the so-called “king” of energy sources, is the fossilized remains of plants that lived more than 200 millions years ago. This means all the energy contained in coal ultimately came from the Sun. A lump of coal is thus a bundle of compressed ancient sunlight.
By the same token, the energy of oil is ancient sunlight in liquid form, whereas natural gas is ancient sunlight in gaseous form.
Given how most of our electricity is produced using fossil fuels, and how almost all of our vehicles are fueled by them, we can say that the modern world runs on the energy of ancient sunlight.
A lot of great things were built using the energy of ancient sunlight. However, we cannot keep on relying on ancient sunlight forever, or even for very long.
First, because it will eventually run out. The amount of oil, gas, and coal in the ground is not unlimited. Sunlight, on the other hand, will be around for another billion years and more.
Second, because using the energy of ancient sunlight releases the ghost of ancient living things in the form of carbon dioxide. And these ghosts were not happy to have been awaken from their eons of slumber, and they haunt our atmosphere by trapping excess heat, giving the Earth a fever that wrecks that delicate balance that made our civilization possible in the first place.
Third, because we now have found a way to power our civilization using recently sunlight. We have found a way to harness the power of the wind, waves, and water, all of which ultimately derive their energy from recent sunlight. We even have learned how to directly harness the energy of sunlight itself.
Our generation it at a crossroads. One road leads to the destruction of the climate that has allowed civilization to flourish. The other leads to a world where we leave the ghosts of ancient life forms on the ground and, like a sunflower, flourish on power of recent sunlight.