Solar panel waste may not be nearly as bad as we once thought

Re:Solar panel waste may not be nearly as bad as we once tho... by hgomersall on Sunday November 13, 2022 @03:35PM (#33587062)

Let's consider the numbers... A decent modern combined cycle gas turbine can achieve 60% efficiency, so let's take 50% to be conservative. Transmission losses are generally better than 15%, so that leaves a combined efficiency of 42.5%. A pessimistic charge/discharge efficiency for lithium ion would be 80% and I'd expect the charger to be 90% efficient, which gives us a total (pessimistic) efficiency of 31%.

An internal combustion engine has an optimistic efficiency of about 30%.

So, even if we ignore all the losses in fuel distribution for ICE cars and ignore regenerative effects in electric cars and the ability to incrementally decarbonise the grid, electric still has a slight advantage.

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Re:Solar panel waste may not be nearly as bad as we once tho... by Retric on Sunday November 13, 2022 @03:49PM (#33587188)

Those are incredibly pessimistic numbers for power plants and optimistic numbers for ICE. On average 5% of the electricity transmitted and distributed in the United States is wasted your other numbers are similarly inaccurate.

ICE engines are only ~30% efficient under optimal conditions, idling still consumes fuel and engines idle a lot in normal driving including coasting down a large hill, slowing down, stoplights etc. Similarly turning on and heavy acceleration etc is extremely inefficient. This is where the primary benefit comes for hybrid cars not regenerative breaking.

Also, comparing gasoline to electricity ignores all the energy required to make gasoline. Oil refineries both use serious amounts of energy and release massive quantities of CO2 directly.

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Re:Solar panel waste may not be nearly as bad as we once tho... by hgomersall on Sunday November 13, 2022 @04:26PM (#33587518)

Indeed, I merely wished to bound the problem.

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Re:Solar panel waste may not be nearly as bad as we once tho... by thrown_22 on Sunday November 13, 2022 @05:11PM (#33587914)

You're missing the engine efficiency. Which is another ~90% efficiency process. That brings it down to be lower than an ice.

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