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0 pointsbko2y ago0 comments

Sorry if this is a stupid question, but if solar is cheaper, why isn't it the dominant energy source today?

Seems like a win win, people get cheaper energy all without force. Generally the market chooses the best product, which is why we replaced horses crapping all over our cities with cars. It wasn't legislation or some global consortium of governments that phased out the horse, it was a better product. What am I missing here?

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rout395742y ago

Momentum, installed base, established interests, changing uses.

Foolishly reductionistic model: at the instant that solar becomes defacto cheaper, if everyone immediately changed, you'd need at least [total world power consumption / solar panel production rate] years to change over.

2022 world electricity consumption was about 25000 TWH. That envelope-backs to about 2800 GW if the sun is always directly overhead everywhere and there are no transmission losses.

In 2022, we installed about 228GW of solar panels. Assuming constant production (HAH!) that says it should take more than a decade to replace the existing demand. Which will of course stand still for us.

Apply whatever multiplication factors you like about what percentage of the year a given real solar cell will generate power; about how quickly folks are convinced to change; about the construction of projects which were planned before this price threshold was passed; about the impact of using grid power to do transportation work which was previously done by pumping dead dinosaurs...

The confounding factors abound. But that's an ignorant sideline answer to why. :)

cesarb2y ago

> if the sun is always directly overhead everywhere [...] Apply whatever multiplication factors you like about what percentage of the year a given real solar cell will generate power

A simple but useful back-of-the-envelope estimate would be 25%. Half of the day, there's no sun, so you have 50%; the other half, it increases gradually until the middle of the day, then decreases gradually until the sun sets. Simplifying this to a linear increase and decrease, if you plot it into a graph you'd have a pair of isosceles right triangles, which cover half of the area, so you have another 50% over that first 50%, and the end result is 25%.

(IIRC, the real result for the single-axis trackers you'd find on grid-scale power plants is something like 30%, showing how good that simple back-of-the-envelope estimate is.)

Symmetry2y ago

Here in the northeastern US, the permitting process for adding new power plants to the grid is long and cumbersome in a way that is usually the long pole in adding new generation to the grid when the new generation is as quick to put up as solar. We have more solar power in the process of getting approval than we currently have installed.

konschubert2y ago

Yes, it’s a total win!

It’s dominant already in newly added capacity. It just takes a while, mostly due to permission processes taking long.

And limited grid capacity, which is also held back by environmental review and nimbys - at least in the western world.

gruez2y ago

Problems with storage and/or grid connection.

enqk2y ago

Because money is the wrong thing to use for decision making, we should be tallying resources and energy expenditure. Money is an imperfect proxy for something akin to human labour and related activity, and does not encode information about physical resources being used

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