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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.
And typically get most of their power from coal.
You could stick a couple of square meters of solar panels on a typical car, which at 20% efficiency would give you about 240W on a sunny day. For a half-hour commute (fifteen minutes each way) and eight hours in the car park, that would give you about five horsepower if the battery is 100% efficient and you didn't need to use any other electrical items, like AC or headlights.
So it's potentially possible, but would be a really crappy drive.
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
Even if it is 100% coal power, it is still cleaner and more efficient than gasoline.
There is no need to put the solar panels on the car. You can put them on your garage, or buy solar power from the grid.
Which would be great, if you leave your car in the garage all day. Most of us drive around, so if the panels aren't on the car to keep it charged they're utterly useless to us.
I can't decide whether this was a joke or not. For the benefit of those who might not take it that way, I'll point out that these cars have batteries that allow them to collect energy from their garages and (gasp!) drive around with it.
"I zero-index my hamsters" - Willtor (147206)
Right. The current record for all solar cells is 44%. 27% has been achieved without rare materials.
When you see indium and gallium in the materials list, it's not going to be a high-volume product.
Quite the opposite. See: http://en.wikipedia.org/wiki/Copper_indium_gallium_selenide_solar_cells
"I zero-index my hamsters" - Willtor (147206)
This will revolutionise electricity generation in such diverse fields as, uh... space craft and... um... space stations.
Aerospace uses non-flexible crystalline at about twice the power output, because what matters is more or less watts/Kg. For non-panel satellites with cells mounted right on the satellite body, what really matters is watts/sq meter.
Now you need flexible cells for ... um...
Easy of manufacturing, for one, but more importantly the cost of manufacture (watts/$) is very, very low.
"I zero-index my hamsters" - Willtor (147206)
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.
At about 3" thick, and 3' x 5', I estimate I can get about 20 panels in my minivan. Should be plenty.
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.
I saw an interesting comparison made by a professor: If you covered the entire area that was evacuated because of the Fukushima incident with solar cells, they would produce less power than the nuclear reactor did (not to mention how much more it would cost).
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Eventually you have to buy more power plants too.
25 years is the normal estimated panel life, but I know of panels from the 80s that still work.
And typically get most of their power from coal.
You could stick a couple of square meters of solar panels on a typical car, which at 20% efficiency would give you about 240W on a sunny day. For a half-hour commute (fifteen minutes each way) and eight hours in the car park, that would give you about five horsepower if the battery is 100% efficient and you didn't need to use any other electrical items, like AC or headlights.
So it's potentially possible, but would be a really crappy drive.
Nissan Leaf gets 4.5 miles per kWh. So every hour of charging would get about 1 mile, assuming your math is correct.
my karma will be here long after I'm gone
Do the math on a solar powered car.....
Assume you could cover the entire top surface(s) of a small car with solar panels and let them charge batteries all day while the car is parked at work. Assume battery charging is 100% efficient: Panel Area ~4 m^2 (liberal, but I'm trying to make a point) Panel Efficiency 20.4% Time in sun 8 hours Sun angle derate 50% Solar input ~1kw/m^2
Then the batteries get charged with 1*4*8*0.5*0.204 ==> ~3.26 KWH A small car engine is rated at ~200 KW (i.e. Ford Focus Spec at 223 KW) If you average using only 1/4 the available power ===> 50 KW The saved energy in the battery will move you for 60min*3.26/50 ===> ~4 minutes
So, you run out of juice about the time you hit the on-ramp of the freeway.
The point being, this isn't going to work unless you have more efficient cells, more efficient vehicles, more solar panel area, or a combination of all three.
Actually the Nissan Leaf gets about 4.5 miles per KWH. So if the panels on the car really can generate 3.26 KWH in only 8 hours that's 4.5 miles * 3.26 KWH = 14.67 miles just on solar power. That's pretty significant IMHO, that would be worth adding solar panels to the car, even if you have a place to park and charge it at night. For example, let's say your daily commute is 25 miles, that's 175 miles a week. For the sake of simplicity let's say the Leaf gets 87.5 miles per charge, so the user would charge twice a week in this example. If the solar panels generate a 14.67 mile range every day, that's only 10.33 miles being used by batteries instead of the full 25 miles, so instead of charging twice a week, user would charge every 8 days. This is huge, especially for people that live in apartments or other situations where plugging your car in is not convenient, they could bring the car somewhere once every 8 days for a full charging.
my karma will be here long after I'm gone
There are two places were putting solar would give the best bang for the buck. As you said, rooftops. If they covered the entire roof, they should make the roof last longer than without the panels. The other place is over roadways. There shouldn't be any problem with right of ways since the roads are already controlled by the government. Also, you would add protection from the elements to those roads which should both prolong the life of the roads as well as reduce the number of accidents caused by adverse weather conditions. Extra bonus points if location transmitters were added to the panel construction to aid in navigation and/or auto-drive cars.
This is key. Unless your surface area is limited (space craft, vehicles), it's not efficiency that matters, but cost per watt of capacity.
Make solar cheaper per watt than coal plants (we're getting close now), and then watch all the rooftops in the country get covered with solar panels.
Even if all the rooftops combined aren't enough to produce *all* our needs, every 300MW of solar power is one coal plant shut down, and 2400 tons less CO2 produced. Per day.
Pay off that panel in 2/3rds of a year assuming an average 100watt output and $0.10/KWH. Sounds a bit like saying "Let me know when doctors found a cure to cancer, then I will go see one."
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.