Ultimately, all energy on Earth comes from one of two sources: Thermal reactions within the Earth itself, or, more often, the Sun. Since the industrial revolution, humanity has harnessed this energy indirectly in the form of fossil fuels, to the detriment of every ecosystem on Earth. With severe climate change looming, it seems necessary that humanity pivot towards other energy sources, a fact which has not escaped several lawmakers, in the U.S and abroad. Multiple American congressmen have championed the idea of a “Green New Deal”; a massive government-funded push for renewable energy. But even an optimist can’t help but wonder about the feasibility of all this.
So let’s consider solar energy, which is probably the most discussed renewable source. The sun produces all the energy that humanity could possibly want, but in the process of converting this energy into a usable form, some of it may be lost. Currently, the best solar panels on the market have an efficiency of around 35%. Now, a 2013 report states that it usually takes around 3.4 acres of panels to produce 1 million kilowatts a year. To power America, we need around 4 trillion kilowatts, so obviously one acre of solar panels isn’t going to do much good. (4 trillion/1 million x 3.4)/630 gives us 21,587 square miles needed to power the entire U.S. IS that a lot? Yes. Is it infeasible? Given that this is only 3,000 more square miles than is currently allotted for coal mining, I would give an emphatic no. The sunniest parts of America, New Mexico, West Texas, Arizona, and Nevada, are also among the most sparsely populated. Now, to install 1 acre of solar panels costs around half a million dollars. 21,587 square miles would cost around 7 trillion dollars, or a little over a third of America’s yearly GDP. Is this possible? Within one year, no. Within 10-25 years? Quite possibly. Over 2 decades, this correlates to $300 billion/year. That’s around half the current military budget. In other words, the U.S does have the money.
But let’s think bigger. What if we wanted to power the entire world? Well, the entire world consumes around 22 trillion kilowatts of electricity every year. By 2050, we’ll be close to 40 trillion. To meet this energy demand, humanity needs to install 215,000 square miles of panels, or around 75 trillion dollars worth. Using the same pricing as before (though the cost of solar panels will doubtlessly fall significantly in coming years), it would take around 2.5 of the world’s annual GDP every year from 2020 to meet this goal by 2050. Economics then, are clearly the biggest obstacle to an all-solar world. This might seem disheartening, but unlike the physics of energy-generation, the laws of economics are in human hands. If the will to create an all-solar world truly exists, science says it can be done.