Solar + Battery in One Device Sets New Efficiency Standard (arstechnica.com) 42
Ars Technica reports on an international team's demonstration of a device merging photovoltaic and battery hardware into a single, unified device "that can have extensive storage capacity... a device that's both stable and has efficiencies competitive with those of silicon panels."
The resulting hardware can operate in any of three modes: providing power as a solar cell, using sunlight to charge as a battery, or providing power as a battery.
Previous records for a solar flow battery show the tradeoffs these devices have faced. The researchers used a measure of efficiency termed solar-to-output electricity efficiency, or SOEE. The most efficient solar flow devices had hit 14.1 percent but had short lifespans due to reactions between the battery and photovoltaic materials. More stable ones, which had lifespans exceeding 200 hours, only had SOEEs in the area of 5 to 6 percent.
The new material had an SOEE in the area of 21 percent — about the same as solar cells already on the market, and not too far off the efficiency of the photovoltaic hardware of the device on its own. And their performance was stable for over 400 charge/discharge cycles, which means for at least 500 hours. While they might eventually decay, there was no indication of that happening over the time they were tested. Both of those are very, very significant improvements.
The article ends by suggesting this demonstration means researchers can now look for more stable battery and photovoltaic chemistries with improved efficiencies. "Whether all of that is compatible with low cost and mass production will be the critical question. But, at this stage of the renewable energy revolution, having more options to explore can only be a good thing."
Previous records for a solar flow battery show the tradeoffs these devices have faced. The researchers used a measure of efficiency termed solar-to-output electricity efficiency, or SOEE. The most efficient solar flow devices had hit 14.1 percent but had short lifespans due to reactions between the battery and photovoltaic materials. More stable ones, which had lifespans exceeding 200 hours, only had SOEEs in the area of 5 to 6 percent.
The new material had an SOEE in the area of 21 percent — about the same as solar cells already on the market, and not too far off the efficiency of the photovoltaic hardware of the device on its own. And their performance was stable for over 400 charge/discharge cycles, which means for at least 500 hours. While they might eventually decay, there was no indication of that happening over the time they were tested. Both of those are very, very significant improvements.
The article ends by suggesting this demonstration means researchers can now look for more stable battery and photovoltaic chemistries with improved efficiencies. "Whether all of that is compatible with low cost and mass production will be the critical question. But, at this stage of the renewable energy revolution, having more options to explore can only be a good thing."
Well yeah, but will it do THAT (Score:2, Interesting)
Well sure you could so.
BUT will it have a lifetime like this one, 500 hours? You only have to replace this device every 21 days, and it's only a few thousand dollars each time. Heck, that costs barely more than your mortgage.
Mdsolar and EditorDavid must be salivating over this.
I was rude (Score:3)
I shouldn't have thrown in the last line. Sorry about that, you two.
Re: I was rude (Score:2)
Frankly, as a German, that wasn't rude enough for me.
You're pro-unclear (Score:2)
I shouldn't have thrown in the last line. Sorry about that, you two.
I see what you did there. You said the N word without saying the N word.
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Anyone can put a battery and a solar panel into the same case and call it 1 device.
But this is a Solar Panel that is the Battery
So... (Score:2)
So, about the same as existing tech. Cheap (<$1/W, retail) solar panels are around 18%, and decent lead acid batteries will do at least double that. And that's just using existing commodity compon
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So what's special here?
Short lived solar cells, 500 hours, instead of 50 years, progress!
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2. Something newer.
3. ???? Marketing.
4. Profit!
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It uses flow batteries, so potentially vastly more storage.
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One small point. Assuming that the sun comes up and sets once every day, 400 charge cycles works out to about 14 months lifetime for this device. I think for most practical applications, you're going to need about 20 times that long a lifetime.
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Google "flow battery".
It's not that existing tech can't be scaled, just that flow batteries offer much greater scaling opportunities.
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Then remain ignorant for the sake of being argumentative it's your loss. This isn't a debate.
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If you don't know how to google "flow batteries" then you're done.
You should know what they are by now, though.
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You're the Googletard here.
If by that you mean "person who knows how to internet" I guess I'm guilty as charged.
If you can find relevant information by just plugging the most obvious search terms into google, you don't get to whine about people not providing citations. Shit, you could probably even find this information with bing.
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It wasn't an argument, it was the answer to a question. I'm not here to spoon feed you. If you want that, go ask your mommy.
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Willful ignorance is always a bad look.
Everyone who cares about this stuff has already heard about flow batteries.
You're just being a bitch for the sake of being a bitch. You win teh prize!
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The claim wasn't "better energy density", or even "lower large scale cost". And, neither of those are important for "Solar + Battery in One Device", unless you're talking about building a single fucking huge device, which they aren't. It doesn't eve
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I'm well aware of flow batteries. The claim was they can provide "vastly more storage", which is bullshit.
It's not bullshit. They can provide vastly more storage.
For every gallon of special sauce added to a flow battery, you can add another cell to a traditional battery bank. It's not like there's a physical limit.
But there is a practical tradeoff. A flow battery just needs a bigger reservoir. More cells means more cables, which means more copper, or more aluminum and more fiddly-fuck junctions for cables. So which makes more sense is going to depend on lots of specifics.
The claim wasn't "better energy density", or even "lower large scale cost".
Right. But here you are, talking about scale cost.
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https://news.usc.edu/166306/fl... [usc.edu]
https://cleantechnica.com/2019... [cleantechnica.com]
https://www.sciencedirect.com/... [sciencedirect.com]
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Let me help you with the simple math:
We'll pick numbers which support a need for more storage. Middle of the US desert, solar insolence is an average ~6 KWh/m^2/day. So, a 1 m^2 panel, with solar tracking, and with the unrealistically h
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>with just enough storage to get you through a night or cloudy day or two
Probably more than that. If you've got a grid-tied system and just want battery backup for power outages, that's probably a lot more than you need, but given the added cost of inverters, etc. needed to support *any* batteries, maybe that many extra batteries themselves are worth it. Especially if you're prone to power outages due to fires, etc. that can take a long while to repair.
On the other hand, if you're off-grid you probably
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Which makes it even worse. Now you need a _much_ larger array to charge the batteries on the occasional sunny day. When you add storage to support longer times, the footprint of the array scales faster than the footprint of the battery bank.
And, again, I'll point out that the article is about "Solar + Battery in One Device". There's no mention of using external tanks to increase capacity (which would of course make it "not one device"), they're just talking about using flow bat
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If you only get the occasional sunny day, solar might not be for you.
The problem with batteries is the occasional stretch of overcast days - because you probably have at least a few such stretches per year, and you probably don't want to go without power for a few days per year.
Charging the batteries isn't actually a problem - you've got weeks or months to recharge the extra capacity with your the slight over-capacity you need to have for off-grid solar to work without running out of power every day you hav
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That wasn't the claim in the first place.
The comment was about the advantage of flow batteries.
Whether their capacity is actually a significant advantage in this case is another story, but they do have advantages, and disadvantages.
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Then, quick, someone with mod points mark that claim as off-topic.
And even as a stand-alone claim, it was false and unsupported. For every gallon of juice added to a flow battery, another battery can be added to a traditional bank. So there is no "vastly more storage."
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Hold my thin film solar cells! (Score:2)
This technology sounds much more interesting and will maybe go into massproduction before my thin film solar cells.
Like my lawn solar lights? (Score:1)
Not so efficient ... (Score:2)
... if you add in the cost of replacing the damn battery every two years because it lost half its capacity.
Oh man I'm so sick of this (Score:1)