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We have a similar law in France. Something is unclear to me though:

"build a conceptually similar, 657 kW solar carport system across 12 parking lots (shown, above) that delivers more than 1.23 million kWh of clean, emissions-free power annually and offsets the equivalent of 185,000 vehicles’ worth of harmful carbon emissions."

Not sure what that means but that doesn't seem right.



The complete sentence for context:

"Here in the US, we’re proving that out, too – the Northwest Fire District in Arizona partnered with Standard Solar to build a conceptually similar, 657 kW solar carport system across 12 parking lots (shown, above) that delivers more than 1.23 million kWh of clean, emissions-free power annually and offsets the equivalent of 185,000 vehicles’ worth of harmful carbon emissions."


I have to wonder if they are taking into account the AC usage or other factors to get there; When you park in the shade, you don't have to cool your car down nearly as much. This effect is greater in hot deserts with lots of sun. There are likely other benefits to the vehicles and infrastructure.


Which part?

12 parking lots

657 kW nameplate capacity

1.23 GWh per year of energy production

The 185,000 cubicles worth of CO2 emissions is likely based on average pollution per car, and average carbon intensity of the local grid.


The average emissions for a car is 4.6 tons of co2. The average carbon intensity of U.S. electricity generation is around 384 grams of co2 per kWh. 1230000 * 0.384 / 1000 = 472 tons. But 185000 cars emit 851000 tons so 500 tons is like a rounding error, unless I am mistaken.


Either it’s a full on hallucination or they intend the power to be used to charge electric vehicles. Which is a stretch because solar parking isn’t going to sell that many electric vehicles. It will sell some, but not that many more.


1.23GWh is enough to power a few hundred cars, not 185 thousand.


Yeah the longer I look at it the less their numbers make sense.

I also did a double take, “surely it’s not 4.6 tonnes per year”. But it is.

If that came out as a liquid rather than a gas, we’d have stopped burning fossil fuels by now.




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