Solar Panels On Water Canals Could Generate 13GW of Power For California (interestingengineering.com) 117
The little known Turlock Irrigation District (TID) in California has taken a bold and ambitious step to put solar panels on its open water canals, the first such project in the U.S. Interesting Engineering reports: Encouraged by a $20 million grant from the state, TID has announced Project Nexus that will trial the concept on two canal segments, to begin with. The project is the on-ground realization of a study conducted by researchers at the University of California Merced and University of California Santa Cruz. Published last year, the study used simulations to calculate that California's open canal system could save 63 billion gallons of water every year if it put a lid on top of its canals.
The researchers had suggested putting solar panels would help the canals become a hub of renewable energy as they could potentially produce 13 gigawatts of electricity. This is about a sixth of the energy that the state of California generates, TID said in its press release. The solar panels could be installed on top of the canals using suspension cables and the cooling effect of the water running below would also maintain the efficiency of the panels that are known to drop output on very hot days. The 63 billion gallons of water saved could be used to irrigate 50,000 acres of farmland or supply drinking water to as many as two million people.
The researchers had suggested putting solar panels would help the canals become a hub of renewable energy as they could potentially produce 13 gigawatts of electricity. This is about a sixth of the energy that the state of California generates, TID said in its press release. The solar panels could be installed on top of the canals using suspension cables and the cooling effect of the water running below would also maintain the efficiency of the panels that are known to drop output on very hot days. The 63 billion gallons of water saved could be used to irrigate 50,000 acres of farmland or supply drinking water to as many as two million people.
"Meatloaf energy", that's what this is. (Score:2, Insightful)
Okay, so we put a bunch of solar panels over the canals in California. They they realize that the solar output peak is the same time as the midday valley demand as people go to lunch. The peaks in demand is in the morning and evening when the sun is dim, people have their lights on, they are cooking meals, they need to run heating or air conditioning. So they put batteries on the grid. But batteries only help when there's a sharp drop or peak in demand, and when energy is stored for hours or maybe days.
Re:"Meatloaf energy", that's what this is. (Score:5, Insightful)
Then comes another problem. There's years where the sun shines less than other years. The solar panels wear out. So they need more but they already covered all the canals.
"Let's not build 13 GW worth of solar panels because it may actually be only 10 GW later." Yeah, brilliant thinking. Just like "let's not grow food because some of it will go to waste." Surely we won't go hungry that way...
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There seems to be a trend of people going looking at a superior technology, and then finding a disadvantage on it and using that disadvantage no matter how minor, to become a major reason to stick with the current very faulty system.
LED Traffic lights don't do a good job melting snow off them like incandescent bulbs. So people get upset when they see them, never mind that they last longer, and don't need the bulb replaced which is an expensive process requiring multiple people that need to manage traffic i
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I wonder how much of it is shills and astroturfing from companies that are going the way of buggy whip manufacturers. Maybe those traffic light incandescent bulbs are very lucrative for whoever makes them and whoever gets paid to replace them.
I mean look at MacMann. Every story vaguely about energy and he's there within seconds with some copy/paste nuclear shilling. You can't tell he's doing it just because he's the world's biggest nuclear power fan. He's got a script set up to alert him when keywords are p
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I sincerely hope the Slashdot copy-paste army isn't actual people. What a waste. Sweet job running a script farm though. Still a waste, but a smaller one.
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The world has a bad case of Nostalgia, and it getting in the way of progress. Because we are so stuck in the good old days of our 15-25 years of age, before responsibility kicks in and puts a dark cloud over everything.
Nostalgia is the enemy of rational decision making full stop. This is why boomers are so dangerous because they grew up in a "golden age" of economic prosperity and upward mobility.
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Sure, if you consider high inflation, high unemployment, and high interest rates a "golden age".
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Inflation is great for homebuyers, as it deflates the mortgage debt ratio. That's part of why so many of them were able to buy and keep houses.
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Inflation raises the price of just about everything. If you bought it already, then inflation will effectively reduce your debt and overall your assets because wages will increase over time with inflation.
Keynesian economics failed in the 1970s (Score:2)
Inflation raises the price of just about everything. If you bought it already, then inflation will effectively reduce your debt and overall your assets because wages will increase over time with inflation.
I guess you missed that high unemployment part, and for those working seeing increases that did *not* keep up with inflation.
Imagine home mortgage rates in the high teens. It was a national crisis at the time. The reigning model of economics theory that ruled for many decades, the keynesian model, collapsed in failure. So you might want to rethink your predictions, they seem a bit keynesian, and that did not work in the 1970s.
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That is stagflation, not inflation.
Yes. However the point remains that Keynesian policies can fail with odd combinations of circumstances. Also we do have a bit of economic stagnation. Administration policies have stopped a lot of production in the energy sector, and exploration. The chip shortage is impacting the auto industry, vehicles going from assembly lines to parking lots since they were manufactured with missing chips. GDP is artificially high due to massive government emergency spending not normal industrial activity. We are seeing
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It's not a trend. It's the same old thing: people are threatened by change and the human brain is pretty shit at logical thought. Put the two together and you have the good old fallacy of composition.
We also seem to have a weird need to feel intelligent. You won't find many people who insist that they're faster than an olympic sprinter, or can play basketball better than Michael Jordan, but there's no shortage of pundits who will point out simple issues with an idea and point and laugh at the silly experts
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Assessments of new technology in use should take into account the cutting edge problems of any newer tech.
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The world has a bad case of Nostalgia, and it getting in the way of progress
Nah we just like complaining.
Its more a fear of v1.0 tech (Score:3)
There seems to be a trend of people going looking at a superior technology, and then finding a disadvantage on it and using that disadvantage no matter how minor, to become a major reason to stick with the current very faulty system.
Its more "new" technology than "superior" technology. New tech always comes with new bugs and new flaws, some recognized but ignored, some not recognized until after deployment. You mention LED traffic lights. Well some early versions had limited visibility at angles. There were numerous cases where cars stopped at limit lines could not tell which light (LED) was illuminated. They all appeared as if off at that angle. Its more a fear of v1.0 tech, which is not an unreasonable fear.
And yes, for this appli
Re:"Meatloaf energy", that's what this is. (Score:5, Insightful)
We can shift demand, e.g. when there is a lot of solar power available have smart EV chargers use it. Electricity consumption patterns are already changing and will continue to do so as we move away from fossil fuels.
Your other arguments are ridiculous. Solar panels wear out? So does nuclear. So does everything.
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>>(on the subject of things wearing out) So does everything.
Stupidity never seems to, sadly.
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We can shift demand, e.g. when there is a lot of solar power available have smart EV chargers use it. Electricity consumption patterns are already changing and will continue to do so as we move away from fossil fuels.
Your other arguments are ridiculous. Solar panels wear out? So does nuclear. So does everything.
During the middle of the day, EVs are at work, and thus not plugged in. And the ones that are plugged in are plugged into slow chargers that can't be forced to charge any faster. Fixing that would likely require subsidizing the cost of L3 charger installation to replace L2 chargers. The cost of doing that would be enormous, however, making this completely infeasible. (Storing power in batteries would be cheaper.)
The best you could realistically do is allow negative billing to end users for power consume
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Workplaces are already installing lots of AC chargers. They don't need to be fast, people are at work for hours.
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Workplaces are already installing lots of AC chargers. They don't need to be fast, people are at work for hours.
In every workplace I've ever been at, chargers are a precious commodity. They use systems like ChargePoint to notify you when your charging cycle ends so that other people can then take advantage of them. And buying chargers with higher amperage costs considerably more money, both in equipment costs and wiring (and, potentially, building service capacity). So reducing the charge rate during periods of high demand just means that fewer people can charge.
Increasing the charging rate during periods of low d
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MacMann (nee blindseer) has been doing this same shit for literally years, under at least two accounts. Presumably he changed accounts in order to obfuscate this fact, but it didn't work at all because he didn't change his posting style at all. But that's true to form with nuclear, which can only be sold with lies. And that's all he has, lies. When you look into any of the citations he [rarely] posts, they always turn out to be bullshit. Presumably that's why he posts less of them than he used to.
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Sorry, but no. Nuclear energy is not some wonderful magic wand, but there are several use-cases for it. OTOH, I'm not enamored of the older plant designs. Perhaps the molten salt thing can do better.
For rapid massive deployment solar beats nuclear hands down. For minimal problems after installation, solar beats nuclear hands down. It's not a really good base-line power source, because it's too variable, but with a good enough backing store it is quite good.
OTOH, the on-going costs are generally underes
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Nuclear energy is not some wonderful magic wand, but there are several use-cases for it.
There are basically two. Space, and war. In every other case there is some other solution which is superior overall.
For rapid massive deployment solar beats nuclear hands down.
Rapid? You mean years behind schedule, and billions of dollars more than projected? I do not think that word means what you think it means.
OTOH, the on-going costs are generally underestimated.
You mean of nuclear? Or solar?
They aren't large, but they exist.
Oh, you mean solar, because nuclear costs are always massively underestimated, and The People always wind up paying at the end.
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but with a good enough backing store it is quite good.
If the problem of storage is solved, then we can move away from CO2 producing sources completely.
Re:"Meatloaf energy", that's what this is. (Score:5, Insightful)
While I am also very pro-nuclear, and I agree that California's power policies are a bit crazy, your point here is laughable. Water canals need to be covered in some manner anyway, to reduce evaporation, and that's the biggest benefit. You may as well do it with solar panels, and even if the yield isn't awesome, so what.
Power is being produced mostly during a less-than-optimal time time of the day? You mean like all the rest of solar installations? Oh I guess we should stop them too, then. And the maintenance! Yep, better shut down all solar.
Or, maybe, we should trust that energy storage research won't stop, and will produce better and better results in time. Or, who knows, using the surplus energy during peak hours. Smart meters allowing parked electric cars to recharge at a lower cost? Desalination plants, and fuel synthesis, as you also mentioned? Atmospheric carbon capture? There are PLENTY of uses for more energy, even if intermittent. Not all processes are easily stoppable/restartable, and not all are necessarily profitable (although free electricity would help a lot in that regard), so that's another area of research. If random slashdot user number 141223 can come up with a list of uses, larger groups of smarter and dedicated professionals can likely do even better.
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"Or, maybe, we should trust that energy storage research won't stop, and will produce better and better results in time." ...) could have enough space for a "cold/heat storage tank" and run their HVAC against that, instead of - for example - the hot ambient air of mid day. The overall efficiency might decrease, but if the prices drop enough it's still a win.
I see more hope in the "consume energy on demand" market than in the "store grid energy now and return it later".
Some places (industrial,
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Any organization that has the cash to buy solar or who can borrow at reasonable rates might as well install panels. They are a guaranteed investment with a great ROI. The technology is mature and proven over decades.
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This is true in California. It's one of the tiny portion of the locations on the planet where there are both people AND solar intensity to make photovoltaics work in an economical fashion.
Questions of things like viability over canals and engineering problems related to it still need to be solved. But in general, in California solar power makes sense as long as their grid has sufficient back up for that much intermittency.
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Desalinization sounds like a good, reliable, dump for energy you can't store. Unfortunately, the process is rather expensive, and what do you do with the brine produced? Leslie salt probably doesn't need that much salt.
Well, there are problems with everything. That doesn't mean you don't do it, that means you look for answers. Holding ponds in the Mojave should evaporate to solid (or near solid) pretty quickly. So you can turn the brine into rock salt for not much more cost than the cost of pumping it
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If you're getting free brine and have cheap land for evaporative ponds, the dry salts should be a gold mine. That's the process that generates our lithium deposits, for example.
If someone was really clever they might even be able to get the evaporated water to increase rainfall on strategic areas downwind.
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Re:"Meatloaf energy", that's what this is. (Score:5, Informative)
Batteries can help even things out between demand and generation, on any given day at any given time, whether the issue is peak demand increasing, or generation decreasing, or the opposite. Generators of all types go offline for various reasons, even nuclear power plants.
Solar panels do wear out as they age, but the production reduction is gradual. They don't just suddenly die one day. Most are warrantied to offer 80% production at 25 years vs day 1. Only the inverters need to be replaced periodically. Panels are not all installed on the same date, so they won't all need replacement on the same day. Some get installed every year, unlike nuclear power plants, which take decades to come online, whereas solar / wind is much quicker.
CA currently imports about 1/3 of its power. Only 9% of the overall power mix is nuclear. Renewables represent 13% already. When renewables drop off (night, rainy or cloudy day, no wind, shorter winter days), batteries can temporary take over while different types of generators are brought online. The hydro and natural gas generators are some of of the quickest to bring online when that happens. Nuclear power plants are some of the slowest to bring online, most taking over 12 hours.
It's still possible to increase the share of renewables a lot, from the overall current overall 13%. It does mean natural gas generators would run at higher capacity in winter time when days are shorter, and might be used less in the summer when solar production is much higher, as much as 3x that of winter some years, judging by my 40 solar PV array. Looking at my own electricity consumption; usage is not proportionally increased by AC in the summer anywhere close to 3x.
Actually, my EVs consume much more electricity in the winter due turning on the heat, and that uses more energy than the cost of AC in the summer. That evens out total consumption from both grid & solar pretty well throughout the year.
https://docs.google.com/spreadsheets/d/1yy-PFK_WMxlRpuD75vVDmeRsnMFbH-YJaQDenyoUOzE/edit#gid=0
This was for the 12 months true up period. That's almost all the energy used to power a 4700 sq ft mansion, and 2 plug-in cars. One Volt PHEV, one Bolt EV. All charging for those cars was done at home. Only about $200 spent on gasoline for the PHEV during that 1 year period.
House is heated by natural gas, though, whereas AC is electric. If home heating was electric, electricity usage would be way higher in winter than summer. I haven't done the math on that, but probably at least 2x. It wouldn't make a ton of sense to burn more natural gas in power plants in the winter to convert to electricity, and then use them for electric heating.
12 months natural gas usage is here, though not for the same 12 months as above.
https://docs.google.com/spreadsheets/d/1EjCW5rfWYDCK2tYszrfCVpG3d4rbE5fMvtaZ007BZEo/edit#gid=0
Looks like I used 702 therms of natural gas between the 2 gas furnaces, 2 gas water heaters, and gas clothes dryer. That would be 20,568 extra kWh per year if switching to all electric, if appliances had the same efficiency. But gas furnaces are generally much less efficient than electric furnaces - as low as 30% efficient vs 80-85% efficient. So, it could be an 54,849 kWh instead by switching to all electric appliances. At the average 19.3 cents/kWh rate we paid last year, that's $10,585 extra electric bill, vs $1297 on natural gas. Ouch! I am not sure I did the math right on this one as 8x higher seems really bad. And of course, 19.3 cents/kWh is insanely low electric rate for PG&E. Only this low because of the grandfathered and soon to be expiring E-6 rate, and medical baseline.
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We paid $0.44/watt for REC TwinPeak 2 panels manufactured in Singapore which have a 20-year output warranty... meaning they are actually derated, and still that cheap despite being from one of the most reputable panel manufacturers in the business. I have two 10-watt panels from like the dawn of solar (one of them was made by Maharishi back in the 80s) and both still have good output.
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CA currently imports about 1/3 of its power. Only 9% of the overall power mix is nuclear. Renewables represent 13% already. When renewables drop off (night, rainy or cloudy day, no wind, shorter winter days), batteries can temporary take over while different types of generators are brought online. The hydro and natural gas generators are some of of the quickest to bring online when that happens. Nuclear power plants are some of the slowest to bring online, most taking over 12 hours.
You just wrote how batteries can back up intermittent renewable energy sources then point to how nuclear power is bad because it takes too long to bring online. Why not use the batteries to manage the peaks and valleys in demand so the nuclear power plant can just be kept running all the time?
You can bring a horse to water but you can't make it drink. When some people are lead to the well of knowledge they prefer to drink the kool-aid. Batteries will help nuclear power just as much, if not more, as they
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Of course storage can be used to take over for any type of generator, and store any type of excess generation, but costs mount rapidly with the expected duration and amounts of storage.
Almost nobody wants nuclear power plants in their backyard running for any length of time, much less all the time. That's why nuclear represents only 10% of worldwide electricity generation, similar to California, and the worldwide share of nuclear power is not growing, and not likely to. Even if people and governments worldw
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Almost nobody wants nuclear power plants in their backyard running for any length of time, much less all the time.
You are very wrong about that.
https://www.herald-dispatch.co... [herald-dispatch.com]
Also, it doesn't matter if people want nuclear power or not, it's what they are going to get. The choice is not nuclear power or not, that's ignoring the real issue. The real issue is that if you want electricity then you will get nuclear power. Sure, you can jump up and down, kick and scream, about not wanting nuclear power but someone is going to have to be the adult in the room and explain to everyone that if you want electricity then you
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I couldn't see your link due to the paywall. Even the headline was covered.
How much do you want to bet there is going to be a nuclear plant in my backyard 10 years from now ? I'll certainly take the opposite side of that bet.
As to opposition to nuclear power being "gone", that's a pretty bold claim to make.
https://news.gallup.com/poll/341828/americans-show-elevated-concern-energy.aspx
39% want more emphasis on nuclear, 28% want less, and 32% want the same as now, ie. status quo.
In 2013, 2 years after Fukushi
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Okay, so we put a bunch of solar panels over the canals in California. They they realize that the solar output peak is the same time as the midday valley demand as people go to lunch. The peaks in demand is in the morning and evening when the sun is dim, people have their lights on, they are cooking meals, they need to run heating or air conditioning. So they put batteries on the grid. But batteries only help when there's a sharp drop or peak in demand, and when energy is stored for hours or maybe days. That means looking for other solutions.
Longer term storage means pumped hydro.
Sigh. Try to keep up with the times...
The grid will become smarter. If there's excess power then a signal will go out and all those electric cars will turn on and "store" the energy. No need for arrays of batteries and/or stored hydro.
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I'm a bit dubious about counting on the electricity stored in EVs to be available for others to draw on. But there *are* various solutions, of which pumped hydro is only one.
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I'm a bit dubious about counting on the electricity stored in EVs to be available for others to draw on.
It would require net metering and variable rate pricing. I'd think some Texans would have been happy to empty their EV's for the $9/kWhr being paid to producers during their big freeze. And, in less extreme circumstances, if consumers could buy cheap solar in the afternoon and sell it for more in the evening, some might choose to pimp out their car batteries to the grid. Given 100kWhr of capacity and $0.05/kWhr price difference, that could net $5/day or ~$2k/yr. For owners that don't use their car's ful
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Wow, what a bunch of bull. I'll touch just a couple of points
They they realize that the solar output peak is the same time as the midday valley demand as people go to lunch. The peaks in demand is in the morning and evening when the sun is dim, people have their lights on, they are cooking meals, they need to run heating or air conditioning.
For warm countries/areas like California, it turns out the PV production correlates pretty well with peak consumption, mostly due to A/C. Sure, the more you rely on on wind/solar, the more you'd need battery storage, but for hot climates solar does have that advantage over everything else. Peak power is usually the most expensive power - you normally have to fire up extra production facilities etc, PV gives you that peak for "free".
Then comes another problem. There's years where the sun shines less than other years. The solar panels wear out. So they need more but they already covered all the canals.
Eh, I have a 10
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I'm sure absolutely nobody thought of any of that, but thank goodness you're here to help California out! And there absolutely isn't any energy storage on the grid in California, at all [insideclimatenews.org]. And everyone knows that air conditioners take lunch off, because they're unionized. And every single lunch that is heated up, is heated with gas and not electricity.
“Essentially that battery is able to operate like a natural gas power plant for four hours,” he said. “In a place like California that’s really important because of how much solar California has, and the sun goes down every day. The plant is able to provide a lot of support to the grid to help it transition from it’s daytime solar into its night time usage of other power plants.”
So that basically knocks down your unqualified assertion that "batteries only help when there's a sharp drop or peak in demand" and absolutely proves that yo
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Peak demand is not typically in morning or evening when everyone is home cooking meals. It's when all the businesses are up and running and using electricity while the A/C demand peaks in the afternoon.
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Peak demand is not typically in morning or evening when everyone is home cooking meals. It's when all the businesses are up and running and using electricity while the A/C demand peaks in the afternoon.
Depends on the country, state. And it also depends a bit about what you actually call "peak".
I suggest to google "load curve" or "load profile" for the region you want to talk about, and also include that region in your argument.
E.g. the peaks in Germany are around 11:00 in the morning and 17:00 in the after
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Reduced base load demand for coal and natural gas during the day decreases or stabilizes the cost of coal and natural gas. It's ok if we have more daytime capacity than we need.
Leaky panel contribute to chemical contamination? (Score:2)
Okay, so we put a bunch of solar panels over the canals in California.
Are they designed for and/or rated for use with reservoir water? Rain could transfer contaminants from the panels to the water, especially as they age and degrade. They develop leaks and rain runs across internal components and electronics, etc.
FWIW I used to live near a reservoir in Southern California and there was numerous restrictions on what could be done nearby. The reservoir itself was pretty much off limits. Apparently water treatment plants require their inputs to be pretty clean. They are deali
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And earthquakes! Will nuclears be able to hand big quakers?
No comment. (Score:1)
Replying to try to undo mis-moderation.
While we're at it... (Score:1)
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That cover should survive the hurricane-speed winds created by the supersonic train.
Panels lose efficiency when it's hot? (Score:3)
Re:Panels lose efficiency when it's hot? (Score:4, Informative)
Welcome to physics. Only some of the photons have the correct energy to jump the electrons over the band gap. The rest turn to heat.
Silicon gets more conductive as it gets hotter, so it gets easier for the hopped up electron to get back to ground state without going through the electrical circuit. So efficiency drops.
The cadmium telluride PV panels actually do better in hot conditions. You could use those if you are really worried.
Putting PV panels over canals and reservoirs is one of the better ideas out there. Certainly better than covering up farmland or clearcutting forests to make space.
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Resistance goes up as things get hot.
Depends on the conductor.
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Already being done in India (Score:5, Informative)
Re: Wind resistance (Score:2)
How do the structures fare in high wind?
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Without any particular knowledge of the experience in India, I'd surmise: about as well as any structure. If you design for it, it's likely to handle it just fine. If not, then you take your chances. Even in the case of "properly designed" structures, you can still end up with failures. It sucks, you'll get some isolated losses that need to be repaired or replaced, but these things happen and you move on. In short: this is hardly unique to solar canals. The ri
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The shade values of panels is definitely worth considering. I sometimes use long-term parking at the Phoenix airport and, not surprising, covered parking rents for more than uncovered. I ran some numbers on solar covered parking, and concluded that the shade would be worth ~10x the electricity produced! And, if you need a shade structure anyways, the returns on the marginal cost to make it solar can be pretty good.
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Save Diablo Canyon (Score:3)
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People will have to run their air conditioners during the day when the sun is out. It's a sacrifice, but I think we can manage.
Hackaday (Score:2)
Hackaday had an article recently about the pros and cons of putting solar panels over canals and reservoirs.
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Yep. They already did this in third world India.
Some NIMBY will object (Score:2)
Some genuinely misled, some knowingly pretend concern, ... Even it just delays the project, every day i
Solar panel weakness highlighted .... (Score:2)
.... did you know they are less efficient on hot days?
The frustration about reading anything about 'renewables' is that like the 'fossil' fuel industry before them, any negatives are hidden. You repeatedly discover the weaknesses only as an aside in some marketing campaign or academic paper touting why their product or process is better than what exists. Also never a mention of life cycle because all renewables just last forever ... I guess.
Anyways, seems like a good idea to cover canals ... even without
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So are coal plants.
investment considerations (Score:2)
"California's open canal system could save 63 billion gallons of water every year if it put a lid on top of its canals. "
The prevailing westerly winds would normally carry that evaporated water to Nevada and the rest of the US. Sealing it in the canals keeps it in California. Our (Southern CA) gain is everyone else's loss, so there's that. And since the US taxpayers are covering much of the cost, that too is worth considering.
But it is not just for the benefit of the privileged people of CA; most of it is f
Re:investment considerations (Score:4, Insightful)
The prevailing westerly winds would normally carry that evaporated water to Nevada and the rest of the US. Sealing it in the canals keeps it in California. Our (Southern CA) gain is everyone else's loss, so there's that.
This would be interesting to analyze in depth, but intuitively I'm wondering if the effect will be quite small. I would imagine that whatever humidity is contributed by this evaporation is completely dwarfed by what's happening over the ocean, for starters. Secondly, preventing evaporation from the canal doesn't mean the water never evaporates - much of it still does, it just might do it when it is sprayed over a lawn, or transpired out of leaves, or flooded over a field. Even if it's soaked into groundwater supplies, that will likely be released when things dry out and tree roots pull up the water from deep in the earth. So you're generally adjusting the time and location of evaporation, but not necessarily the total amount.
There will certainly be impacts to microclimates near the canal though - I would expect temperatures in the immediate vicinity of the canals to rise since they will no longer enjoy the cooling effect of all that evaporation.
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The interior of North America isn't dry because there isn't enough open water to the west. You might have noticed a reasonably large body of water there. It's dry because all that moist air goes up over mountains and dumps its water on the way.
Increased Maintenance Costs (Score:2)
What this article and many proponents fail to acknowledge is how this type of project significantly impacts the ability to monitor and maintain theses canals. It makes inspecting the canals more difficult and what would normally be a simple patch repair becomes a much more involved operation. Having extra water doesn't help if you can't move it anymore.
I'm not saying don't do it, but the impacts need to also be quantified and discussed.
Sudden outbreak of common sense (Score:3, Insightful)
More efficiency, less regulation (the already own the canals), less evaporation - it's things like this that show there's really a tremendous amount of low-hanging fruit to do things far better than we currently do. If people would stop the doom and gloom + political infighting and focused more on this type of problem solving we could really make some progress.
I like that idea (Score:2)
Government pork that doesn't solve either problem (Score:2)
It's great that they are going to reduce evaporation from California's irrigation canals. That doesn't solve the root problem that they are pumping Millenia of groundwater out of deep wells to grow groceries in the desert.
Making it worse, the solar power part of this is lipstick on a pig. They'll never recover the cost or carbon impact of building the foundations and scaffolding across the canal to support the panels. Add in the cost of the many microinverters required for a long skinny solar farm and it
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They'll never recover the cost or carbon impact of building the foundations and scaffolding across the canal to support the panels.
And why?
What is the difference between scaffolding on a simple field or over a channel? CO2/energy wise?
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The CO2/energy difference comes from the support materials under the scaffolding that mounts the panels.
"Normal" solar panels are mounted to a lightweight steel or aluminum scaffold "racking" that has a steel support post set in concrete every 2-4 meters/6-12 feet.
"Truss Canal" panels are mounted to racking as well; That part is the same. The difference is what's under the racking. The proposal is effectively a 50 foot wide mile long pedestrian bridge that has to be rated to for the dead load of the panel
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I doubt there will be any difference in the scaffolding for solar panels mounted on an open field versus one over a channel. The wind is the same, as well as any other requirements.
Also.. (Score:2)
It's not a canal (Score:3)
Maybe (Score:2)
Maybe it's a good idea, or maybe it will end up a maintenance nightmare, have too many losses in the long transmission lines, and possible leach stuff in runoff into the water.
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Or use those space lasers to boil the canals, and run the state on steam.
Or chop up all the forests for firewood, since they're going to burn up anyway.
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Do both. There is little reason not to build the solar canals outside of initinal cost as they also help with evaporation and being they are literally on top of water sources chances are a pumped storage battery could be built inline with them as well.
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Water is fundamentally fungible. If you reduce evaporation along canals, you also reduce the amount that needs to be drawn from aquifers.
Re:Or more likely... (Score:4, Insightful)
"need" is relative
95% of the water Los Angeles needs falls on it ever year (the stories of it being "in the desert" are highly exaggerated.)
Unfortunately 99% of it runs directly into the ocean because they've capped off the land with pavement.
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According to this ultra right wing source, LA imports 85% of its water:
https://angeles.sierraclub.org... [sierraclub.org]
Some of it comes from as far away as Wyoming. The city will not be able to avoid desalination in the near future.
Roofing the California Aqueduct with solar panels is not so much about saving evaporation but avoiding the costly fights with Hollywood lawyers that make building any sort of infrastructure so exorbitant.
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If you don't let water run into the ocean, environmentalists get upset.
Re: Or more likely... (Score:3)
That is backwards. If you do let runoff run directly into the ocean, environmentalists get upset. The land does not naturally shed water that fast. When it happens it creates brackish water offshore in places where it is normally salty, which has negative consequences for marine life. It's naturally occurring flows like rivers that environmentalists prefer reach the ocean, because the organisms living around river mouths are adapted for that. When you change things a new order has to develop and that not on
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Actually it's both ways.
No matter what you do, environmentalists get upset.
It's how they keep themselves in business.
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The objection to roofing California's freeways is going to be concentration of automotive emissions that could poison the drivers below. This problem will gradually go away as ICE is replaced by electric vehicles, but why not start by roofing over that long rural stretch of I-5 between Bakersfield and San Francisco?
They could also roof over the route of the California High-Speed Rail line. It's not like there are ever going to be trains running on it.