This one drives me nuts. This story about a pilot project to put solar modules over canals in California has been going around for a couple of years now.
https://www.pbs.org/newshour/economy/solar-panels-built-over-water-canals-seem-like-a-no-brainer-so-why-arent-they-widespread
Here's the problem: "covering California’s 4,000 miles of canals with solar panels that could also generate 13 gigawatts of power. That’s enough for the entire city of Los Angeles from January through early October"
Other reports cited the output as “13 GW per year.” BZZT !
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Both references are using a RATE unit to describe a QUANTITY. Incorrect! And that same error has been repeated ad nauseum for two years now, because apparently none of the bazillion journalists who repeated it know the difference!
I actually tried to find the source in the study, which was 47 pages of complex, jargon-laden, techno-economic analysis but I could not find a rolled-up estimate of power or energy, so I’m not sure where that 13 GW came from.
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I actually reached out to the UC Merced researchers asking for clarification, but they did not respond to my inquiry. So on we stumble in our energy-illiterate press, making simple errors every damn day that would get a journalist laughed of any other beat because the editors don't know any better either! 🙄 Hell of a way to go about covering the most critical story of our time, folks. The blind leading the blind.
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@chrisnelder @ljbo 13 GW is from the UC Merced press release. https://news.ucmerced.edu/news/2022/solar-paneled-canals-getting-test-run-san-joaquin-valley
The paper doesn’t include an extrapolation as far as I can see, but they include 117.5 W per 0.72 m^2 panel (assuming 0.8 x 0.9 m)—Sup Table 6. The CAD drawing is 20 panels across the aqueduct (0.8 m x 20 = 16 m width). 6437 km x 16 m / 0.72 m^2/panel is 143,044,444 panels x 117.5 W is 16.9 GW.
@chrisnelder @ljbo interesting article on the origins of the UC Merced paper and a bit more detail on the troubles experienced in India.
@jim_smoot @ljbo Interesting. Thanks Jim. I’m eager to see how the next projects pan out. I remember driving along the California Aqueduct around 2005 and thinking it would be a great place to put some solar, but knew it would be a long, difficult path to making it happen, so I didn’t pursue it. I wish them all the luck!
@chrisnelder About 14 GWh. The difference looks like the energy used by diesel pumps after cursorily reading. That’s one of the goal of the project to remove them.
@ljbo Perhaps. I have to run now but I don't suppose you tried adding up any of those columns to see if they came to 13 GWh?