Nikola Tesla once said, “electric power is everywhere present in unlimited quantities and can drive the world’s machinery without the need of coal, oil, gas, or any other of the common fuels.” He was referring to research he was doing on what he called “cosmic rays” but his words can be interpreted today to support the use of the energy supplied by solar radiation. According to NASA, our nearest and dearest star, the sun, emits approximately 3.8 x 1033 ergs/second, or about 5 x 1023 horsepower/second or 3,814,254.84 watts/second. Enough, according to NASA, to “melt a bridge of ice 2 miles wide, 1 mile thick, and extending the entire way from the Earth to the Sun, in one second.” To put it in a more Earthly perspective, we humans with our ipods, boob-tubes, magic finger mattresses and other electric must-haves consumed a mere 1,523.552 watts in the year 2008. The sun is an astoundingly bountiful source of free energy that literally rains down from the heavens every second of every day and the great thing about it is that harnessing that energy is so easy and so “low-tech” that even a grade-schooler can do it. Why isn’t our entire civilization doing it? Instead of diving down the political, conspiracy rabbit hole that inevitably ends in rants about reptilian overlords and illuminati puppet-masters, I will simply lay out the beauty and simplicity of solar thermal energy production technology. I’ll look at the pros of it in contrast to the cons of other sources of power and review where it is being utilized in our world and what plans there are for its future.
When I was in elementary school in the early 1990s, I was fortunate enough to live near the Shenandoah Environment and Education Center in Newnan, Georgia. My class was treated to what I remember as fairly regular field trips to the center where our young, fertile minds were enriched with all sorts of activities designed to foster environmental awareness, activism and technological curiosity. One of these activities I remember vividly as it not only sated my hunger for knowledge but my literal hunger as well. It was a solar hot dog cooker. Using only household items like a shoe box and tin foil, I learned it was possible to harness the power of the sun to actually cook a hotdog. This was a watershed for me that eventually led to the demise of hundreds of innocent insects by way of solar death ray in mine and my friends’ backyards but I digress. This simple technology can actually be used to create very large amounts of power–enough to energize entire cities. Plus, the footprint for this energy production might as well be non-existent when compared to those of nuclear, coal, gas and oil because there is no non-renewable fuel to mine, there are no waste products and there are even imaginable scenarios in which there need not even be an actual single-use facility campus taking up valuable real estate.
The concept behind generating electricity is remarkably simple. I think most ordinary people probably imagine that the power coming through the outlets on their walls comes from some magical place beyond the realm of the average person’s understanding. This my friends, is not the case. Power plants, though obviously complicated systems as a whole, are simply a means of turning a turbine generator. Even the most complicated nuclear power plants simply provide a heat source that generates steam to turn a turbine generator. The sad part of this is that, as mentioned previously, the environmental cost of these plants is just too high. Especially when we consider the alternative, solar thermal plants. Coal and nuclear require strip mining mountain tops, a non-renewable process that creates toxic slurry that seeps into drinking water, endangers the lives of miners and their families and leaves irreparable scars on the landscape.
Once refined and taken to the plant, some coal gets converted into energy but the rest gets burned off into gases and particulates that pollute the air, water, wildlife, etc. and nuclear produces un-usable, toxic nuclear waste that has to be buried and stored for thousands of years before it becomes benign enough to be assimilated into the ecosystem again. None of this even addresses the fact that the actual plant campuses, in addition to the millions of acres of mines required to keep them functioning, monopolize hundreds of acres in their own right. To paraphrase writer Ted Nace, “overall, based on figures compiled by the U.S. Army Corps of Engineers for the years prior to the Surface Mining Control and Reclamation Act (1977) and by the Office of Surface Mining for the subsequent years, approximately 8.4 million acres of land have been surface mined in the US alone. Continuing the current rate of surface mining for the next half-century would require approximately 7 million more acres to be surface or longwall mined. That estimate is based on the presumption that the quality of coal and the thickness of ore veins will not decline over time. Realistically, such a decline is unavoidable, based on the “good business” practice of mining the best and most accessible coal first. So 7 million acres is a conservative estimate and does not take into account land used for the construction of new coal-powered plants.”
Solar thermal power plants require only heliostat mirrors, some fancy plumbing and the acreage required for said mirrors and plumbing. The obvious joke to be made here by any witty (unlikely) critic of solar thermal power is that it’s just a bunch of “smoke and mirrors,” but anyone making that claim simply has their facts wrong. Reality emphatically invalidates them. To borrow from Nace again, “Based on the current mix of mining techniques, a solar thermal plant like Blythe [The Blythe Solar Power Project is a solar power station under construction in Riverside County, California.] will produce 18 GWh per acre of land over a 60-year period. In contrast, a coal-fired power plant will produce 15 GWh per acre of mined land. In other words, the land footprint of coal is about 20 percent bigger than the land footprint of solar thermal.”
In the country of Spain, just on the outskirts of the city of Seville, lies the PS10 Solar Power Station, Europe’s first commercial solar power plant. Rising up out of the countryside as “Top Gear” host James May puts it, “like a modern cathedral for the worship of some forgotten deity,” is a series of aesthetically-pleasing towers and mirrors, which are part of a larger project set to produce enough green energy for 180,000 homes, or most of the city of Seville. The completed project will produce over 300MW, will include towers, two more of which are under construction, photovoltaic power plants and a mixture of newer parabolic solar collectors which will be installed at a later date. The entire power project will be fully operational by 2013 and will generate zero greenhouse gas emissions.
It’s incredible that this will be accomplished using the same principles behind frying an ant with a magnifying glass or cooking a hotdog with tin foil on a hot day. I imagine that if our ancient ancestors in Egypt and Babylon had mastered the unassumingly important
technology to produce good mirrors, our civilization might be more advanced by more than a millenium (the first modern silvered-glass mirror is credited to German chemist Justus von Liebig in 1835). Of course that’s only my conjecture.
To continue on my course of conjecture, I can imagine a design scenario in which this amazing technology could be utilized to power our cities while sacrificing zero real estate for the purpose. The answer is rooftops. These solar towers and mirror arrays could be built in cities atop already existing buildings and would not only give us all the green energy we need and utilize currently useless rooftop real estate, but would reflect sweltering solar radiation away from our streets and buildings effectively putting it to use powering our lives.
Speaking of un-used or un-useable real estate, some estimates put desert as comprising approximately a third of the Earth’s land surface. This land is not arable, it is uninhabitable for humans and it is bombarded daily by sweltering sunlight with zero obstruction. Why not build solar thermal plants on it? It’s sitting there right now doing nothing but providing habitat for scorpions and pit vipers. Why not put it to work? That idea is precisely what is behind a large portion of the European Union’s plan to overhaul European energy consumption over the next 40 years. Current estimates state that only 0.3 percent (approximately 6500 square miles) of the Sahara desert would need to be covered by solar energy production plants in order to power the whole of the European continent in addition to Africa and the Middle East.
Of course there are hurdles to switching to this technology but I believe they all can be overcome and that the benefits both fiscally and environmentally are well worth the trouble. We should rid ourselves of the insanely complex infrastructure inhabited by the fossil fuel industry and trade it for a simple, clean technology that takes advantage of the renewable, ubiquitous power source that the sun provides our planet 24 hours a day, seven days a week.