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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."
As opposed to the really efficient gasoline engine. Oh wait - that's only 25% to 30% efficient, and doesn't fuck up the air you breath.
Not only are gasoline engines inefficient, they require fuel be trucked to stations wasting even more fuel.
Transmission losses like that just make it even worse.
Right, because we all know that power plants use gasoline engines to generate electricity? Yeah, no.
Oh and natural gas plants have near 60% efficiency. Coal and oil are in the mid 40s and nuclear in the lower 40s. So yeah, it's still at less than half the efficiency of other generation.
The fossil fuels burned in those power plants are nothing but stored solar energy. Given how much solar energy has had to shine on this planet for half a billion years in order to store enough coal or gas to run those generators, the overall efficiency of fossil fuel generation is absolutely abysmal.
I calculated that my daily commute would requite 3 kWp of panels if the end-to-end efficiency was 75% - which is what Tesla claims for the Model S. 3 kW of panels is 12 panels. That easily fits on my garage roof. This isn't as insane as it sounds.
If the input is virtually inexhaustible (sunlight), it doesn't matter how efficient it is. If you have half the efficiency, just double the solar panel area. Total cost per kW and per kWh becomes is more important. Mind you, the panels *don't* need to be on the car.
Ezekiel 23:20
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.
You forgot one little thing, a solar powered car does not have to have the solar panels on it. The solar energy can be captured somewhere else and then the car can be recharged with this power.
Much like your current gasoline powered car does not have to drill a well every time you can to fill up.
It's the cost that matters more than efficiency. I don't need a 20% efficient panel that costs 10 times what a 10% efficient panel costs. Really I just want some inexpensive but durable panels. Something where I can recoup my costs in 3 or 4 years not a decade or so.
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=
If you actually sit down and DO the math, even if you covered the US with solar panels you cannot cover US yearly electrical requirements.
Assuming your numbers are correct, lets say our solar radiation conditions are 10% of the best case. Then to provide all the electricity the U.S. needs, we'd have to cover 1.3333% of the total surface area.
Of course, we can choose the best available locations for each additional panel, so we can do a whole lot better than 10% of the best case. If we can only do half as well on average, the number comes down to .267%. And we can use at least some surfaces for their original use and for solar energy production (rooftop panels).
There are lots of difficulties between here and full solar power. I doubt we'd ever want all our electricity coming from solar power. And even .267% of the surface area of the U.S. is an enormous amount, and acquiring rights to that land would probably be impractical. But if we did need to do it, space wouldn't become the limiting factor for a long time. And if we could solve all of the other logistical problems--storage, distribution, manufacture, maintenance--we would have enough surface area to provide for the U.S.'s energy needs via solar. It just wouldn't be the best way to go about providing electricity.
Something that is fungible means any one instance of it can be swapped with any other instance of it without changing its effects - electricity is electricity, whether it comes from a solar panel on your roof or a nuclear power plant via the grid. http://en.wikipedia.org/wiki/Fungibility
There are two places were putting solar would give the best bang for the buck.
One more: parking lots. Here in San Jose, we have solar panels over several large parking lots. No additional land is needed, and you get the side benefit of shade for the parked cars.
It is what? I am not a native English speaker, and I have looked for this word in my dictionaries.
In that case, it means "tastes good with mushrooms". :)
Ezekiel 23:20
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.
Ok, let's do the math. Total electrical consumption (not all energy usage, just electrical) for the US is about 480 gigawatts. Average insolation is about 1 kw per square meter. At 10% efficiency, that means about 100 watts for every square meter of panel. That means you need 4.8 billion square meters of panels. 4.8 billion square meters can fit into a square 69.282 kilometers on a side. That's somewhere between the size of Rhode Island and Delaware.
Even if you expand that to all energy usage, not just electrical, you're talking approximately 3 terrawatts. So, that's about 30 billion square meters of panels. That's a square about 173.2 kilometers on a side. That's somewhere between the size of Maryland and Hawaii.
So, if you actually sit down and DO the math, you can easily cover US electrical requirements and, in fact the total US energy usage (not counting food energy and not considering the fact that much of that energy usage can't currently be converted to electrical) without coming remotely close to covering the US with solar panels.
Of course, if you'd actually done the math on your own claims, you would have realized that, when you claimed that you could "optimistically" supply 7.5% of the US's electrical supply with 0.01% of the surface area, that would mean that you could "optimistically" supply 100% of the electrical supply with 0.133334% of the surface area, or even pessimistically (let's pretend that the difference between "optimistic" and pessimistic is an order of magnitude) with 1.33334% of the surface area.
So, it's pretty clear that you either didn't do the math yourself, or you just decide to bluff. If you meant something else, like that there are logistical problems in covering that much area, then say so.