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The ‘solar canals’ making smart use of India’s space

bbc.com

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Re: The ‘solar canals’ making smart use of India’s space

#51

Post by newyankee »

trackone wrote: post #47
yaacov wrote: post #9

There 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-califor...

A quick google search found this PDF as my first result: 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…

smaller width canals are more suited in terms of the cost of the structure to support the panels or so i feel ?

Re: The ‘solar canals’ making smart use of India’s space

#52

Post by Pfhreak »

whatshisface wrote: post #40

> 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?

I 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.

Re: The ‘solar canals’ making smart use of India’s space

#54

Post by soperj »

blacksmith_tb wrote: post #49
soperj wrote: post #46

Earlier quoted context omitted.

Despite 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.

That would be a strong argument against new hydropower projects, but now that those dams are built, it seems like we have sunk costs (pun not intended) that would make it a bad choice to decommission, if we'd have to wait 100yr for the forests to begin to recover? That seems to jibe with critical studies I see [1]. 1: http://blogs.edf.org/energyexchange/2019/11/15/long-consider...

That's not true. Decomposition of trees happens over a long period of time in a anaerobic environment. That's what causes the large methane emissions.

Re: The ‘solar canals’ making smart use of India’s space

#55

Post by soperj »

Alupis wrote: post #48
soperj wrote: post #46

Earlier quoted context omitted.

Despite 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.

OK, 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.

See sibling comment. Practically zero emissions is false. It results in over double the GHG emissions per year than a coal fired plant producing the same amount of energy.

Re: The ‘solar canals’ making smart use of India’s space

#56

Post by marcosdumay »

soperj wrote: post #46
walrus01 wrote: post #21

Earlier quoted context omitted.

I 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.

Despite 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.

> it turns out that Hydro is actually worse than all fossil fuels in terms of GHGs

That's a bad comparison. You can't simply compare them without any context.

Hydro has a one-time high carbon cost, while fossil fuels have a small ongoing cost. You can't simply state that one is better than the other, you need at minimum to restrict the comparison into a time-frame.

(By the way, nobody does a large hydro project without first cleaning out the previous vegetation nowadays. Historical data isn't good either.)

Re: The ‘solar canals’ making smart use of India’s space

#57

Post by soperj »

marcosdumay wrote: post #56
soperj wrote: post #46

Earlier quoted context omitted.

Despite 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.

> it turns out that Hydro is actually worse than all fossil fuels in terms of GHGs That's a bad comparison. You can't simply compare them without any context. Hydro has a one-time high carbon cost, while fossil fuels have a small ongoing cost. You can't simply state that one is better than the other, you need at minimum to restrict the comparison into a time-frame. (By the way, nobody does a large hydro project witho…

It's not a one time cost is what I'm saying. The trees in the forest that is flooded decompose slowly, and release methane the entire time. Specifically to BC, the entire ecosystem also got screwed, the fish in tributaries, up and down from the dams have mercury poisoning.

Re: The ‘solar canals’ making smart use of India’s space

#58

Post by kjeetgill »

Johnyma22 wrote: post #24
yaacov wrote: post #9

There 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-califor...

"don't lose much water" in CA... I doubt the CA case study lends itself too much to the Indian environment.

Yea, 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.

Re: The ‘solar canals’ making smart use of India’s space

#59

Post by Baeocystin »

throwaway_pdp09 wrote: post #33
stuaxo wrote: post #32

Earlier quoted context omitted.

The BBC page didn't seem to load at all, clicking the link above. BBC is a bad choice as they don't have traditional ads, just ones for their own content. Another note: the preference to disable JS is not surfaced in Firefox unless you go to about: config, so it is a little fiddly.

Finally, some feedback! thanks. The link I see is https://www.bbc.com/future/article/20200803-the-solar-canals... and it works fine for me. What do you see? I'm very surprised about the JS, when I used firefox (I now use palemoon) it was under preferences. Noted, thanks.

Not the person you replied to, but to add to the subject, just uBlock Origin on Chrome and the page loads in a second or two, with 11 elements blocked. If I also disable Javascript(1), it loads even faster, but the difference between the two is on the order of half a second, so minimal in practice.

((1) I use the Quick Javascript Switcher extension https://chrome.google.com/webstore/detail/quick-javascript-s... )

Re: The ‘solar canals’ making smart use of India’s space

#60

Post by marcosdumay »

soperj wrote: post #57
marcosdumay wrote: post #56

Earlier quoted context omitted.

> it turns out that Hydro is actually worse than all fossil fuels in terms of GHGs That's a bad comparison. You can't simply compare them without any context. Hydro has a one-time high carbon cost, while fossil fuels have a small ongoing cost. You can't simply state that one is better than the other, you need at minimum to restrict the comparison into a time-frame. (By the way, nobody does a large hydro project witho…

It's not a one time cost is what I'm saying. The trees in the forest that is flooded decompose slowly, and release methane the entire time. Specifically to BC, the entire ecosystem also got screwed, the fish in tributaries, up and down from the dams have mercury poisoning.

It is a constant amount emitted, for generating power during the entire lifetime of the plant. While fossil fuel plants emit an amount that is proportional to the power they generate.
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