This came up at Class-M, in relation to Moore’s Law. Moore, a co-counder of Intel, discovered a trend in the increase in speed of computer processors. Basically, the number of transistors in a chip doubles every two years. This trend is expected to increase until at least 2020 and maybe longer.
So, someone suggested that solar power may follow this same law and we can be completely solar in less than 20 years.
I tend to disagree for a couple of reasons . On the other hand, there are some interesting developments in solar power efficiency that have been recently discovered. These developments may take a few years to go from the lab to the real world, but when they do, the effectiveness of solar power will increase dramatically (probably with a similar increase in cost.)
So, here’s a brief survey of recent advances in solar power.
An Irish company has produced a material that can increase the efficiency of solar cells by 1%. Now that doesn’t sound like much, but 1% adds up when you consider the amount of solar power panels constructed each year. The United States alone had almost 1,256 Megawatts of grid connected photovoltaics panels in 2009. A 1% increase in these systems would result in an additional 12 Megawatts of available power (enough to run about 9,000 homes).
That’s a 1% increase, what about a 30% increase? Researchers at Micro- and Nanotechnology Research Group of the Universitat Politècnica de Catalunya in Spain have created silicon solar cells with 20% conversion rate. Normal solar cells have about a 15% conversion rate. The conversion rate refers to the amount of electricity created from the sunlight that hits the panel. Of course, a group in New South Wales has hit 24% conversion efficiency. That’s almost double the amount of energy from solar panels currently in use. Now, they are trying to figure out how to make these comercially available.
This one is slightly different thandirect conversion of light to electricity. Instead, what about converting light directly into hydrogen to make fuel for fuel-celled vehicles? Researchers at Oak Ridge National Laboratory claim to have developed a system for converting sunlight and water, directly into oxygen and hydrogen. This one is very cool, with organic proteins reacting with synthetic polymers. Very advanced stuff.
Stanford reports that using organic materials can result in a 3 fold increase in efficiency. This system has a maximum efficincy of about 31%, double what we’re currently getting with solar panels. And keep in mind, these are some of the first results, research is continuing.
This is just a brief couple of advances. Keep an eye on sciencedaily and you’ll see lots of advancements. The trick, of course, is making them commerically viable, which means cheap to build. If subsidies to fossil fuels were spent in research on alternative fuels (the subsidy money is about 50% of the entire US federal research budget.)
 I do agree that we could be completely based on renewable power within 20-30 years. This includes the change from fossil fueled vehicles to mostly battery vehicles, with fossil fuel for long distance travel only… although (idea!!!).
Solar however, I don’t think can do it by itself. But combined with wind power, I think it’s easily doable with today’s technology, given the political will to make the leap.