[Manuel_D]

Some energy markets are already hitting saturation periods for renewables. This creates diminishing returns, where more and more of the energy generated from an intermittent source isn't actually used. We were promised that storage would be made cheap enough to capture this excess energy and release it during hours of under-production. But so far nothing has delivered storage at competitive costs.

Furthermore, renewable generation varies a lot by region. Solar's cost per watt is way different in California or Hawaii than it is in Massachusetts. This is both in terms of less sunlight (inclination of the Earth, plus weather) but also land costs. This could be ameliorated by long-distance transmission, but that has its own problems even within small states [1]. And we'd have to increase the net-cost of deployments to match.

There's none of these asterisks and hand-waving with nuclear. Heat water, spin a turbine. Energy where you want it, when you want it.

1. https://www.vox.com/videos/22685707/climate-change-clean-ene...

[ncmncm]

Not true. Storage is not built out because you need a lot more top-line renewable generating capacity, to charge it from, to make it worth building. So, the money is overwhelmingly-better spent on generating capacity, meantime. Thus, it is being spent there.

Storage cost is falling even faster than solar or wind ever did. Some storage pilot projects have been abandoned as alternatives undercut them, as happened to concentrated-solar when fixed-PV cost fell below the cost of tracking mirrors.

But you have already had this explained to you, several times over. Pretending not to know about it is not a good look.

[Manuel_D]

The goal of the Paris accords is to have zero emissions by 2050. Not just zero emissions from electricity, but all emissions eliminated: transportation, industry, and heating too. Just the electricity usages amounts to 500 GWh per hour for the US and 2.5 TW globally. Storing even just 4 hours of storage (a modest goal, many renewable plans call for days of storage) is outside the scope of anything we could deliver through existing options.

The plan for renewables is to build until saturation is reached, then burn gas while we cross our fingers and hope that an invention makes storage effectively free.

[ncmncm]

You can repeat this until you are blue, and it will still not be true.

Also: the Paris accords are for net-zero. That means no more carbon emissions than carbon reclaimed and sequestered. (Carbon reclaimed and then burnt again does not count.)

[Manuel_D]

Sequestration is an even bigger moonshot than storage. Most of the "carbon offsets" are in the form of payment in exchange for other countries to agree not to cut down forests. It isn't actually removing carbon from the atmosphere.

Actually removing carbon dioxide from the atmosphere is the stuff of scientists and PR moves. Nobody has a serious plan to remove carbon dioxide from the atmosphere at relevant scales. The only example I can find would capture only 900 tons of CO2 per year.

We'd need to build 4 nuclear plants for each one that exists in the US to have a 100% nuclear electrical grid. It's something that we've done before, we would reach this goal early if we built plants at the same place we did in the 1960s and 1970s. This doesn't rely on a moonshot succeeding.

Renewables rely on a storage breakthrough or a sequestration breakthrough (but if we have the latter we could just keep using fossil fuels anyway). Relying on any kind of breakthrough yielding a 1,000x improvement is very reckless. You can insist until your lips turn blue that we just need to some type of electrolysis invention of another breakthrough of thermal storage and it's surely right around the corner. But until storage or sequestration is on the market, there's no real plan just hope that some breakthrough will happen.

1. https://www.climatecentral.org/news/first-commercial-co2-cap...

[ncmncm]

It would take until well after 2050 to build those, and they would cost many, many times as much as renewables + storage, and produce zero kWh in the meantime. Just the money spent on coal, in the meantime, not counting nuke construction, would be more than the cost of building out enough renewables.

No "breakthroughs" are needed for storage. Everything works already. All that is unknown is which will end up cheapest.

But you already knew all of this.

[Manuel_D]

> It would take until well after 2050 to build those, and they would cost many, many times as much as renewables + storage, and produce zero kWh in the meantime.

Again, no, if nuclear power plant construction was carried out at the same rate as it was in the 1960s and 70s it'd be completed on time. You might be doubtful that we'd be able to manage that pace of construction in the 21st century, but at least there's precedence for that pace of construction actually being achieved.

> Just the money spent on coal, in the meantime, not counting nuke construction, would be more than the cost of building out enough renewables.

That's a very bold, source-less, claim you're making. Unfortunately the numbers don't even remotely add up. At a total of 535 million tons, and 36.14 dollars per ton for electric power consumption, we're looking at only $20 billion dollars of coal sales [1]. And that's generously assuming that all coal production went to electricity. If you're including power plant construction, that figure doesn't change much [2]. It's so small it's hard to see on the graph, but it appears to be below $25 billion dollars [3].

> No "breakthroughs" are needed for storage. Everything works already. All that is unknown is which will end up cheapest.

Right. We know something will make storage incredibly cheap. We don't know what kind of storage it will be. We don't have examples of it being delivered at that cost. But we just know it in our heart that something will save us and make intermittency a non-issue.

This is called "hope" and it's not a plan. The plan is to keep burning natural gas while wind and solar aren't producing, and keep our fingers crossed that our miraculous something will come about.

1. https://www.eia.gov/coal/annual/

2. https://www.eia.gov/todayinenergy/detail.php?id=45076

3. https://www.eia.gov/todayinenergy/images/2020.09.10/chart2.s...