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Swiss Federal Lab Claims New World Record For Solar Cell Efficiency
Zothecula writes "Scientists based at Empa, the Swiss Federal Laboratories for Materials Science and Technology, have set a new efficiency record for thin-film copper indium gallium (di)selenid (or CIGS) based solar cells on flexible polymer foils, reaching an efficiency of 20.4 percent. This is an increase from a previous record of 18.7 percent set by the team back in 2011."
Before somebody brings up 40% efficient cells, this efficiency is for a single layer. The 40%+ efficiencies are for so called multiple junction cells which are basically several solar cells stacked on top of one another. This record is for a single layer, for which 20% is really good.
Also, comparisons with petrol engines efficiency are kinda pointless since the advantages and disadvantages of solar is environmental impact and cost respectively. Nobody really cares if it is more or less efficient than petrol. What people are concerned about is environmental impact and cost, which are not easily compared by looking at the efficiency.
Please stop perpetuating the myth that "most" of our electricity - at least in the US - comes from coal. Coal has been the source for less than 50% of our electrical supply for nearly a decade now and is still declining (Currently around 40%). Even in the worst-case scenario (Colorado, where the local electricity mix is the "dirtiest" in the country) an EV like the Nissan LEAF has the same carbon footprint as a Toyota Prius. It only improves from there.
Also, electricity is fungible. Putting solar panels on your roof to generate electricity during the daytime peak hours even if your car isn't home charging more than offsets the electricity you consume during off-peak hours at night, both in quantity and quality. If anything you are doing more good by putting PV power into the grid than by using it, since you are offsetting peak-generating capacity which is virtually always fossil-fuel based and adding load to soak up off-peak spinning reserve, improving efficiency and reducing energy waste.
=Smidge=
The fukushima evacuation zone has a 19km radius. Half of which is sea, so this gives around 500km2 of evacuated area.
The Golmud Solar Park in China with a similar latitude produces 317GWh per year on 5.64km2 and costed around 500 million dollars.
So on 500km2 you would produce 28'000 GWh per year and it would cost 44 billion dollars.
Fukushima produced according to wikipedia 29'891 GWh in the year 2009. Building a 4'800 MW nuclear reactor would cost you around 15 billion dollars. But if you include insurance, waste dispossal, dismanteling and opperating costs, you double or tripple this cost.
So your correct it would produce less energy per year, but only slightly. And the overall cost would probably be higher but also only slightly.