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Comment by gpm

4 months ago

You understand that fossil fuel and nuclear plants are typically less reliable (have a lower availability factor) than that right? Every form of power generation has downtime, and needs balancing with other types or accepting that downtime. Solar tradeoffs low mechanical complexity for higher environmental dependence, but ends up with similar (in fact less) downtime here under unfavorable assumptions (100% of energy coming from a single point source of solar, constant energy load not your typical lower energy from consumption energy at night, no ability to shed load with price signalling or curtailment).

The last 3% is left alone because it's the fair comparison to other energy sources... tilted in the direction of favoring the other energy sources.

> It’s the only thing that is interesting, considering you just hand-wove that last 3% of reliability

The 3% issue doesn't come from seasonal variation, it comes from short term weather patterns where you might have a week of heavy cloud cover. Seasonal variation is trivially solved by simply increasing the multiplier on nameplate capacity (and the 6x for Los Vegas includes that increase). It's always going to be easier to generate an extra 25% energy than to store 25% of your energy produced in summer and use it in winter.

> “backup generators” and “transmission lines to other places”. Both immensely expensive items if they are idle 97% of the time.

On the contrary both things that exist anyways. Every place that cares about consistent power already has backup generators for when nonsense happens like power poles being blown over. Transmission lines exist to allow sale of excess production. It's only at tiny scales where these things aren't pre-existing and at those tiny scales overbuilding solar and batteries even more is so much cheaper than the alternatives (like building redundant gas plants disconnected from the grid, or even just redundant diesel generators) that they win by a mile.

An understated win of the storage model here is that these generators don't have to be able to supply the entire load, they just have to be turned on in advance when the weather forecast says there might be a problem to slow the drain on the batteries.

PS. I don't know what country you're from, but it seems a bit crazy to me that you apparently used to have a nuclear industry but apparently don't have a national grid... If you have actual weeks where the sun doesn't shine and no grid... you aren't in a sunny place... so you can still brute force it of course but done efficiently a lower percentage of solar makes sense.

Fossil Fuel and Nuclear Plants are extremely reliable, surpassed only for coal. You're doing a rhetorical sleight of hand by deliberately confusing scheduled downtime with reliability.

You keep on citing dubious numbers from the Big Green lobby, but the reality is. There's not a single place on this planet where after a certain threshold of penetration solar and wind haven't made supply less reliable, haven't caused economic sustainability issues to generators and haven't made power absurdly more expensive to customers.

Not to mention the frequently forgotten issues of toxic waste in production and decommissioning, the toxic fire hazard of giant battery banks and the pathetic short useful life of intermittent power infrastructure. Not to mention the environment impact of such big land gobblers, cynically overlooked by the same folks that decided to destroy nuclear with mountains of bureaucratic red tape deliberately created to suffocate it by ignorant green politicians.

Solar may have a bigger place, in countries with plenty of sun like Brasil, the Middle East or North Africa where residential and commercial consumption peaks with air conditioning usage during peak solar production, and with long days, but even then, absent some magical storage technology that doesn't exist yet, with limits.

Pretending scheduled downtime and rare emergency shutdown of dispatchable power sources are the same as intermittent sources of power is getting to the point of a disingenuous argument. They are not remotely comparable, and they are typically not correlated outages. You simply overbuild these sources by a tiny percentage to account for such things - no one cares if 5% of your nuclear goes offline randomly. It’s not the same thing as 100% of your solar going away at exactly the same time.

Cherry picking Las Vegas - a desert - for solar is also somewhat silly. The midwestern US would be much more like a global average. I could also choose Alaska if you want silly arguments.

Seasonal also doesn’t mean seasons - it means seasonal in the mathematical statistical sense where every 5-10 years in a spot you get a week or two of both sun not shining and little wind output. No amount of overbuilding capacity will ever solve for that - you need energy storage or available dispatchable sources in the form of chemical, hydrocarbon, hydro, or nuclear.

The last 3% is almost all that matters when you are talking grid reliability for the masses and industry. Factories cannot operate without reliable sources of power, and asking every major consumer of power to have backup generation on-site is a massive amount of capital overhead. And completely untenable for perhaps 60% or more of residential consumers.

I’d love to be wrong, but watching everywhere that is getting close to solar and wind saturation is pretty telling. Basically every watt of solar at this point needs to be backed by a dispatchable power source or it’s going to end horribly. It’s great that we were able to replace burning fossil fuels when conditions are favorable - but we need to be real and recognize the costs involved here.

Investing in the natural gas power industry was the easiest layup I ever had investing since this was so predictable in the 2020-2021 green power delusion era. It was obvious to anyone that if solar projects went ahead as projected that natural gas was coming along with it.

I love solar and wind generation and want to see it spammed everywhere possible. I just hate the grifters that currently are endemic to it.