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Another reason why average cost can be deceptive with renewables is that their initial deployment is almost always in the most geographically advantageous region. Then as renewables scale up and spreads out, they must be deployed to less advantageous regions where cost per unit of energy are lower.

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I agree, there are other major issues as well, such as there is no real acceptable way to model an entire grid and electrical system, so a lot of these "full system cost" metrics are open for abuse.

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"Yesterday was quite cold in Alberta and the “cheap wind” dropped to 0.3% at night (when there was no sun available)" Why does wind generated power require sun?

I don't fully understand your analysis or point you are trying to make. Is it that wind is not reliable and this aspect is not part of its cost compared to dispatchable sources of energy?

I also have another question about intermittent energy. Let's say that it is a generally accepted calculation that wind energy has a capacity factor of 40%. Therefore a 1000 GW wind farm actually produces 400 GW of energy. I'm not sure how the capacity is determines or how the capacity factor is measured. In addition, if you look at a daily supply and demand curve for the wind energy operations, there are many times when there is a mismatch of supply and demand. There are times when the supply exceeds demands. How does this dynamic play into the capacity factor? I agree, that just looking at averages for an intermittent source of energy is highly suspect.

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1. the sun comment was just to show that the wind should stand alone at night. It was probably not needed.

2. I presume you mean MW and not GW in your units,

3. In terms of capacity, it's about the amount electricity generated in MWH. Solar works around 6 hours a day in South Africa = 25%, but if you account for clouds and other phenomenon it can be as low as 15%. so if you want the same electricity output in GWyear, or kwh, or mwh, etc then you need to build 4-6 times.

4. But you're right that during a very windy day or strong sun, the instantaneous output can be at full capacity.

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