Solar and Wind are not renewable. The energy from solar and from wind is available but not renewable. An oak tree is renewable. A horse is renewable. They reproduce themselves.
But, and a very important but, the human made equipment used to capture solar energy or wind energy is not renewable. In fact, there is considerable fossil fuel energy embedded in this equipment. The glazing on a solar collector of any kind – solar thermal water, solar thermal air, and solar electric – requires energy to manufacture. Aluminum comes from bauxite. It takes considerable energy to refine the bauxite. When I was fourteen, I worked loading trucks in an aluminum extrusion plant. The ingots of aluminum would be heated, pushed through a die to shape, then cut and put on carts. We would take these carts and move them into a small room heated to around 400 degrees F where they were baked. Because this was Florida, we would be fairly dripping with sweat when we would go into the room to remove the cart. By the end of the day, our shirts were caked with our own salt.
Copper also requires considerable energy to process. I saw a documentary on the History Channel show “Modern Miracles” that followed the mining of copper and the production of products. Mining, refining with both energy and chemicals, drawing the wire, and winding the wire goes into making both alternators for wind machines and motors for solar. There are unintended consequences to the manufacture of solar and wind equipment; including serious air and water pollution, release of deadly chemicals into the environment as well as misuse of humans in mining and processing applications. Besides these unintended consequences, which are critical to a future humane and livable world, there is an accounting method that is important to making energy choices.
There is an important accounting system connected to energy decisions. Any system must give more energy than it takes to create/generate. This accounting system is Energy Invested on Energy Returned (EroEI). When it costs more to pull oil from the ground than we get back, then it is over for that well. On any technology, this has to be a main consideration. Many have heard that it takes as much energy to make ethanol as it provides. This makes it a dead end street.
How many units of energy does it take to make a hot air solar collector or a hot water solar collector or a wind generator or a solar electric panel? Each of the components (aluminum, glass, insulation, wires, pumps, blowers, solar cells, etc.) needs to be computed for the accumulated energy cost of the particular technology. This must be compared to life span energy output of the technology. It is important to realize we are talking about the ENERGY output. The financial payback cost is actually secondary in this perspective. Perhaps these energy devices need an energy content label like food has a calorie label. If a system requires a 1000 units of energy to manufacture and it returns 50 units per year than it takes 20 years for the ENERGY payback. It could take considerably more years for the energy payback. Most “renewable” systems are heavily underwritten by fossil fuels. And many of the auxiliary parts of various “renewable” technologies (the batteries, the high tech control systems) are the weak link for long-term use.
Energy conservation by insulating, weather stripping, and cutting back are the first line of defense toward energy independence and self-reliance. It is important for the future of energy use to be clear on these matters.
These technologies (solar air panels, solar electric panels, wind, etc.) can be looked at as transitional. This means they can help this generation and maybe the next generation ease down the slope to minimal fossil fuels. I am not saying don’t use these devices. I am suggesting we use them wisely. One approach to the use of solar and wind capturing equipment is to realize they can be constructed now while fossil fuel energy is available and relatively cheap. This is a way of creating a bank account of energy by using the existent energy to build equipment that can provide energy in the future. John Michael Greer explores this idea well in The Long Descent. As I indicate above, these technologies can help us ease down the slope towards a world of minimal or no fossil fuels.
As fossil fuels become less available, judicious use of the remaining reserves becomes even more important. We must come to realize that fossil fuels (as well as concentrated sources of minerals) are a gift from the earth and previous to life. To mistakenly call solar or wind energy renewable and include the capturing mechanisms leads to both false hopes and perhaps poor allocation of limited fossil fuels and funds.
