That's not to mention using hydroelectric reservoirs from dams to store energy, which is absolutely fundamental in the mainstream "100% renewable" plans you may have heard of. For example, a lot of Green New Deal stuff largely draws from Mark Jacobsen (the Stanford prof who sued the scientists who published a critique of his plan in 2017). His plan depends on increasing hydroelectric capacity by something like 10x in the USA (albeit, he claims, just by adding turbines to existing dams, though that may be a challenge).

It's really not though, renewables have already surpassed coal in the USA for the first time while hyrdo is treading water. The change already happened and all the concerns about peak load capacity and storage were largely mythical. Coal plants are racing to shut themselves down, the miners are all filing for bankruptcy.

We didn't need to build dozens of new fission plants either. Another myth from the think tanks.

If by surpassed you mean cheaper than building new coal, or even operating smaller coal plants, then yes. Coal generation is still 2.5x wind+solar [1]. Claiming that the intermittent nature of wind and solar is a non issue is a joke. The system can absorb small amounts of intermittent power, but the problem gets progressively worse as the percentage share of the total goes up. We do need, modern, cost effective nuclear, and pumped hydro, and large improvements in grid scale battery storage as well as more long distance transmission to even out the supply.

[https://www.eia.gov/tools/faqs/faq.php?id=427&t=3]

I guess if you want to only look back at 2019 data you will miss the fact that renewables passed coal this year. The rate at which the coal industry is dying is remarkable and is well covered in the media.

Lots of things are celebrated in the media that are not quite true. While in some areas, on some days, renewables are outpacing polluters, their power peaks and wanes at different rates than demand. Coal is still the baseload energy generator, and will be required until massive energy storage is achieved, or we build more fusion/fission plants. With the exception of hydro, most 'renewable' generation stratigies come with temporal issues (wind, sun, tide, etc).

But nobody wants to think about the fact their teslas are runnig on coal, and we assume some random article we saw on renewables outpacing coal are the truth. It is not.

The reason we haven't seen the intermittency issue too much is almost entirely because we are building cheap but very high carbon (~400 gCO2-eq/kWh) fracked natural gas plants. This is not a good or scalable low-carbon pathway.

> The change already happened and all the concerns about peak load capacity and storage were largely mythical.

No they're not. At ~8% I don't see how you can conclude this yet. In the US coal plants were just replaced with natural gas plants. Still a carbon source of power. And these natural gas plants became such a rage in part because of a boom in cheap natural gas. That cheap natural gas boom was provided as a by product of the massive shale oil extraction boom. Which itself was a product of massive amounts of cheap credit that fueled what's probably the largest debt bubble in history, which is currently bursting and taking down a lot of those shale oil companies with it.

With a lot of wells being shut in due to lower oil prices making them uneconomical, we'll have to watch and see what happens to the gas prices. We have just spent half a generation switching from one CO2 polluting source to another, which when all inputs are properly considered is probably just about as polluting. And we did so by wasting a generation of capital. It's been a historical misallocation of capital and it's been entirely green washed.

> The change already happened and all the concerns about peak load capacity and storage were largely mythical

Do you have a link to more on this? The story I recall was that we can't go fully renewable precisely because of storage issues.

>On the other hand, in an era of climate change, it seems like trying to hold on to as much freshwater capacity as possible also seems like a prudent idea, and I'm not sure what the best way to reconcile the two would be.

Climate change doesn't mean warmer temperatures everywhere or a dearth of freshwater. The Hudson Valley area referred to here has plenty of fresh water, is projected to become wetter according to most climate change models, and has become wetter recently (significantly so the last few years).

http://www.cnyweather.com/wxrainsummary.php

I forget the exact numbers, but something like 60% of California's freshwater supply is stored in the Sierra snowpack, and the current models are projecting that California will get more rain overall but vanishingly little snow.

California politically tends to be completely opposed to building new reservoirs, and a large amount of seasonal northern California rainfall ultimately gets routed out to the San Francisco Bay through storm drainage.

The other barrel of this particular footgun is that agriculture is still California's biggest industry and they require an absolutely enormous amount of water. This is already causing strain on state politics, because the central valley keeps demanding more water from northern California, which doesn't want to give up more of it, and southern California has just about drained the Colorado river, and restrictions on water rights are the single biggest driving force behind all the "State of Jefferson" signs you see in the rural northern counties.

I love California but the water situation is about to bite them really hard. "About to", of course, still being a decade or two out, but there don't seem to be any reasonable solutions to this intractable situation on the horizon.

California could trivially afford to just buy out the alfalfa farmers, paying them actually a slight premium compared to the revenue from their alfalfa farming.

That alone would fix most of California's water problem.

You're right, and if I came across implying that was the case for this particular dam removal, I apologize for the miscommunication. On the other hand, the rate of dam removal in the United States has increased, and some of them (especially in the Western US) are in areas that don't experience the same frequency of rainfall, and where even existing reservoirs are often far below capacity. It was more of a general musing that a comment on this particular instance, which from the information in the article, seems like a positive step.

For regions that rely on snow accumulation on mountains in winter and melting into rivers during other seasons, they could be screwed. And plenty of regions heavily depend on that process.

We do have the same issue here in Europe, albeit at a smaller scale. If the old dams can be re-purposed and brought back to use, then that would be a nice compromise.

Some old dams and sluices are beyond repair, though. In those cases it's better to just restore the rivers as far as possible.

That's a fair point. In North America, one of the other things that we should probably consider is the American beaver, which can help with this sort of thing naturally, if they're allowed to. Their activity needs a little management to prevent them from disrupting existing settlements, but compared to effect they had before trappers started in on them, it seems like there's might be some room for a natural solution that checks both boxes to a degree.

Edit: Just kidding, I hadn't realized that the Eurasian beaver had been reintroduced to so much of its original range. Looks like it's not just something for North America.

Yeah, and here in Finland we have North American Beavers too, since someone decided to introduce them in the 30's. They have a somewhat devastating effect on the local forests...

There is a saying in Russian “To kill the beaver, to save the tree”.

In Canada the saying is "save a tree, eat a beaver". I'm not sure if it translates the same way, though.