As far as I’m concerned, this is the defining issue of my generation, and I’m excited to be part of the conversation. There have been a number of exciting conversations taking place regarding the magnitude of the problem, and ways to impact the public policy dialectic, conserve, and live greener. While conservation is an integral part of a comprehensive energy policy, developing energy alternatives to fossil fuels is indispensable if we’re going to maintain our standard of living while averting resource wars in the future. Hence, I’m going to tackle a subject I’m really excited about – the development of commercial solar power utilities.Why am I excited about it? If you think about it, solar power is our only long term viable bet. Fossil fuels will eventually decline in production to the point of not being feasible eventually. Wind and geothermal are fantastic sources of energy, but their power density is limited. Coal is dirty, and will run out eventually too. Nuclear energy is awesome, but expensive; besides, once again we’ll run out. We’ll eventually deplete Uranium (for fission) and Hydrogen sources (for fusion). Most importantly, most of the earth is drowning in sunlight – the sun drops 8 kilowatts of power per square meter in the American southwest, for example.
Besides, solar is finally near commercial feasibility. The US Department of Energy, several states, and several countries have been quietly tinkering with the development of commercial solar power. Their findings, in a nutshell, are that solar can be a high power density energy source and solar collectors can put barren desert land to productive use. The 10 megawatt Seville, Spain PS10 and the 64 megawatt Nevada Solar One plants are among the first photovoltaic power plants to go online for commercial purposes. The Nevada plant uses parabolic trough solar power concentrators, which hold the promise of even higher higher power density than standard photovoltaic panel installations used for home water heating. The massive SEGS (Solar Energy Generating Systems) installation is a collection of nine plants in San Bernadino using parabolic troughs producing 354 MW of power (about 5% of total peak power required in Los Angeles).The 11 Megawatt PS10 Solar Generator in Seville, Spain
There are two exciting developments to surface recently. The first is audacious goal to provide 100% of the U.S.’s power needs via compact linear fresnel technology (CLFR) , which is commercially feasible according to Palo Alto-based Ausra’s Chief Scientific Officer, David Mills. From Scientific American’s coverage of CLFRs:”Ausra will rely on a different type of concentrating solar power plant to deliver on this promise. French physicist Augustin Fresnel showed in the 19th century that a large lens, like the parabolic troughs of the existing solar-thermal plants, can be broken down into smaller sections that deliver the same focus.” Mills goes on to say “The maximum you can get into the grid is about 25 percent from solar,” including photovoltaics, but once you have storage, it changes from this niche thing to something that could be the big gorilla on the grid equivalent to coal.” That’s critical to switching over use of solar – not as an intermittent, niche product but as a mass market product which replaces rather than supplements non-renewable energy sources.
Further research on a longer time scale involves bypassing the limitations of inclement weather altogether by collecting solar radiation in space using geostationary satellites. Space-based solar power would use a roughly half mile-wide solar panel arrays to gather sunlight in orbit. The idea is to beam power down to Earth in the form of microwaves or a laser, then converted to electricity. Sounds like science fiction more than science, right? To be fair the U.S. abandoned the idea in the 1970s as economically unfeasible. The tide seems to be turning, and increasingly mainstream science is embracing the idea. However the economics of photovoltaics has changed radically since then, making the mathematics work according to the U.S. National Security Space Office. The recent Pentagon agency report is a shot in the arm to an idea considered ingenious but commercially unfeasible. While any such technology is more than a decade away from any proof of concept, what’s exciting about this is the change in thinking.
The key take-away here is that we’re starting to apply “sustainability” (fail-over) to sustainable power. Executed properly, there is the potential to turn the U.S. from the world’s biggest energy importer to possibly one of the world’s biggest energy exporters. It’s a win-win scenario: not only are we getting cleaner air, lower environmental impact, more reliable locally produced power, and refuge from oil price instability, but we’re also shifting from outsourced job to locally supplied jobs. Wouldn’t that be neat?