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The ‘solar canals’ making smart use of India’s space
- rblatz 6y agoThis is an awesome idea that I hope SRP adopts here in Phoenix. We have plenty of sun, and canals crisscross the whole valley.
- raducu 6y agoAren't the metal structure that can bridge the gap more expensive than the ones planted on ground? If land is expensive, then it might be worth it.
- SECProto 6y agoIf it's a standardized width and they can be assembled and trucked in, the price difference might be minimal compared to ground mounted (which also need metal structure, just one with supports spaced closely together). Increase the span, use a bit heavier gauge square tube and have a 2d truss structure
- AlotOfReading 6y agoFun fact about those canals: many of them are close to 1,000 years old. The modern incarnation largely follows the old Hohokam canal system, though some of the newest, most expensive parts carefully deviate from it.
- m463 6y agoThat's a fascinating observation. I guess it makes sense, sort of like roads probably cross mountains where there used to be animal crossings, then human trails.
- quaintdev 6y agoOfftopic > The emissions from travel it took to report this story were 0kg CO2. The digital emissions from this story are an estimated 1.2g to 3.6g CO2 per page view. Isn't 1.2g per page view huge amount? I wonder if we can have api for this.
- magnio 6y agoAccording to Website Carbon Calculator, each page view produces 2.22g of CO₂. I think it would be lower if you use an ad blocker. https://www.websitecarbon.com/website/bbc-com-future-article-20200803-the-solar-canals-revolutionising-indias-renewable-energy/ https://www.websitecarbon.com/website/bbc-com-future-article...
- walrus01 6y agoI really have no idea how they're calculating that other than a lot of hand-wavy math. It will vary greatly depending where you are. If I'm in Vancouver and I access CDN or hosting resources from a massive datacenter located in WA or OR, it's highly likely that 98% of the energy for my home, and all of the telecom/ISP sites in between, and the datacenter itself are all hydroelectric powered.
- adrianN 6y agoThat power could be used elsewhere in your power grid. It probably makes sense to look at CO2/kWh averaged over the whole grid.
- soperj 6y agoDespite our government repeating it over and over, it turns out that Hydro is actually worse than all fossil fuels in terms of GHGs (over double coal) depending on what you flood. If it's forest, it's the worst. For the W.A.C Bennett dam in BC, 350,000 acres of former forest land was flooded.
- Alupis 6y agoOK, but it's not being re-flooded constantly, it's already done and can't reasonably be undone. So, long-term, it's a fantastic renewable resource with practically zero emissions.
- yaacov 6y agoThere was a proposal to do this to the California aqueduct, but it turns out they don’t lose much water from evaporation and it would be cheaper to put them on land. https://green.blogs.nytimes.com/2011/04/20/could-the-california-aqueduct-turn-into-a-solar-farm/ https://green.blogs.nytimes.com/2011/04/20/could-the-califor...
- llukas 6y agoCA aqueduct proposal was floating panels. Not suspended above the canal.
- Johnyma22 6y ago"don't lose much water" in CA... I doubt the CA case study lends itself too much to the Indian environment.
- kjeetgill 6y agoYea, I think the parent was just discussing a similar project in California. They probably didn't mean to imply anything about the Indian project. Sorry you're getting buried.
- trackone 6y agoA quick google search found this PDF as my first result: http://watermanagement.ucdavis.edu/files/4114/3891/2385/A01_Burt_Good_Shachar_Pascual_ESM121_FinalReport.pdf http://watermanagement.ucdavis.edu/files/4114/3891/2385/A01_... According to that paper, 700 miles of canals lose 9300 acre feet of water per day. They say the price per acre feet (in 2015) was $107. Almost a million dollars per day is lost according to that paper. And California hasn't been cooling down since 2015. It looks like the paper looked at one section of the canal and extrapolated the evaporation loss to the rest of the canal system in California. *this paper seems to be from a class at the university. Just using it as an example that it might be more evaporation than stated above
- newyankee 6y agosmaller width canals are more suited in terms of the cost of the structure to support the panels or so i feel ?
- kstenerud 6y agoThis is great in theory, but if they cover all the canals it will significantly hamper Knightboat's effectiveness. https://www.youtube.com/watch?v=uoV1-fsFCmw https://www.youtube.com/watch?v=uoV1-fsFCmw
- dhosek 6y agoThere's always a canal!
- mywacaday 6y agoWhat about the impact to birds insects and animals that access the canal for water?
- deleted 6y ago[deleted]
- dan-robertson 6y agoLooks like they could fit through the gaps in the side. I doubt it would take them too long to find that, especially if they knew where the canal was
- hexagone 6y agoThese are V-notch canals, made of cement and carry fast moving water. Not many creatures will try swimming or drinking in it. There are smaller mud canals that carry water from these to the field. Insects, birds, and animals can be found there.
- masklinn 6y agoIf you look at the pictures, the canals are not enclosed, it's a roof with large openings between the panels as well as on the side.
- detritus 6y agoCreatures like shade too.
- renewiltord 6y agoThis is very cool. I love it. These canals are not particularly pretty so I think the panels are an upside in aesthetics. Look very futuristic.
- newyankee 6y agoThis helps control evaporation losses as well, the water flow in canals is more predictable which helps. Also there is a great potential for floating solar especially behind existing hydro as the grid infrastructure almost exists.
- elongatedMusku 6y agoI wonder how this would affect the climate, the rains especially.
- raducu 6y agoGiven that a square of 300X300km would produce enough electricity to power the WHOLE WORLD, and 300X300km square of ocean is such a minuscule thing, I'd say -- no measurable impact.
- xaedes 6y agoA good point from a dead comment : "I wonder how this would affect the climate, the rains especially." Reducing water evaporation should have some kind of effect. Does anybody know of weather and/or rain effects due to these evaporation preventing floating black balls on reservoirs?
- CyberDildonics 6y agoYou might want to check the numbers on the cost of enough solar panels to actually affect evaporation enough to make any change in local climate.
- usrusr 6y agoLess evaporation losses means more water will reach irrigation networks where it will evaporate anyways (either before or after temporarily becoming part of a plant)
- toper-centage 6y agoThe reduction of evaporation is negligible when wete talking about affecting local climate. These are man made canals after all.
- vishnu_ks 6y ago> The running water helps the panels to remain cool, which increases their efficiency by at least 2.5-5% Pretty neat side effect.
- whatshisface 6y ago>To maximise the absorption of energy, the solar panels should face south, but the canal’s direction cannot be dictated. Why does the panel have to be tilted forwards along the row? Can't it be tilted in any direction relative to the others?
- m463 6y agoThat sounds like a useful optimization. Maybe it's a practical necessity for a uniform support structure that faces either upstream or downstream. It would be interesting to see the math - it might only buy a few percent at certain times of the day and be a wash when the sun is overhead. It might also depend on the demand curve.
- clomond 6y agoFor every spot on earth there is an optimal angle of a solar panel / plane to capture the maximum amount of light (Even at any given moment in time). It is for this reason that panel for panel, the most efficient way of operating a given panel are with “duel-axis” trackers. [1] In the absence of these, and factoring in the complications involved with an always operating mechanical component, you can have a “fixed axis” which is the theoretical best point for that place on earth. Most racking systems assume a rigid NxN rectangular grid, so having something that is commercially out there that follows the space exactly may be tough. [1] https://en.m.wikipedia.org/wiki/Solar_tracker https://en.m.wikipedia.org/wiki/Solar_tracker
- gumby 6y agoTrackers are expensive and require maintenance. About 10 years ago The cost of the trackers exceeded the cost of land and panels almost everywhere, and so you Don’t see them anymore except in very unusual applications.
- Pfhreak 6y agoI would guess that it's easiest to manufacture a linear row of panels, and install N hundred copies of that row following the path of the canal. Otherwise each row of panels would need to be either made bespoke or adjusted on site.
- floatrock 6y agoA much better example of multi-use space than solar roads.