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Comment by slfnflctd | Hacker News Reader

> Attaching four hours of storage to a solar generation farm, just enough to get through the duck curve, is now slightly cheaper than coal

This completely ignores scenarios of extended cloud cover, cold temperatures and low wind (somewhat like we just saw in Texas) where properly winterized baseline power would be the only way to keep everything up the whole way through.

Barring future unknown tech, we will always need either nuclear or natural gas if we want five nines of uptime in our electrical power. There is just no practical way currently to build enough storage across the grid to maintain 100% uptime during a week or more of reduced renewable generation.

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If your grid covers a large region and you have sufficient transmission, then somewhere, there is excess electricity from wind/solar that you can bring in.

Remember, we're talking about a world where building renewables to 4x peak demand would be actually economical.

This works on the same principle as an insurance market: it's likely that even at 4x capacity, your local solar farm has a few cloudy days. It's highly unlikely that your entire regional grid generation falls below demand. That probability falls (super?-)exponentially in the size of the region.

Taking a step back: yes, renewable power is intermittent and you need electricity here, now. Either 1) transmit from elsewhere, 2) store locally, or 3) supplement with a stable source (nuclear / thermal). The choice simply comes down to cost (to provide a given level of reliability).

The most efficient solution is likely to do all of the above, taking local conditions into account. Adjusting for local conditions is one thing that a (well-managed) market helps tackle.

This is a dangerous and wrong assumption. Weather events can have high area. What do you do if a hurricane comes at the same time as high cloud cover?

You plan for the worst case, same as we do now.

Sure, but solar plus wind does not allow the flexibility to plan for the worst case and come out ahead.

Wind across enough longitude is impossible to not exist at all given temperature differentials creating wind and the rotation of the earth. Wind compliments solar beautifully because things cool off at night from the lack of sun making it produce more power then. If the earth no longer rotates across the axis or the sun goes out the lack of power is irrelevant to in that worsr case scenario.

This is not sufficient. Wind doesn't have to not increase at all, it just has to be down somewhat, or be too high.

you know that after a hurricane it's way harder to restart a nuclear power plant than a wind turbine right? it's incredible hard to power a nuclear plant if your grid is destroyed. basically you can't start a nuclear power plant with no power at all.

Nuclear reactors never completely turn off. They have generators that can supply the necessary power to run baseline systems and to restart them at any time.

that is not true, when there are disasters they sometimes get shutdown, to not have another catastrophe.

and even then just "restarting" it, is not as easy as restarting software.

We know from Fukishima that generators fail.

What do you do if you have to shut down the nuclear power plant in bad weather for some reason? Build a new one as a backup? There's always a weak link if you want to find one, nuclear, wind or whatever.

> What do you do if you have to shut down the nuclear power plant in bad weather for some reason?

You don’t. If your plant is properly designed, you’re absolutely immune to any extreme weather conditions.

Heck, we have nuclear-powered vehicles sent beyond our galaxy and they’re still working.

Nuclear power is literally the only form of energy we have that can work under virtually all environmental conditions.

Nuclear fission works even in vacuum.

It doesn't just have to be designed right, it has to be built right. Like Fukishima where the design engineer resigned during construction over how low the sea wall was built. The sister plant which was closer to the epicenter had the proper sea wall and as such it was totally fine despite the higher waves.

The problem with nuclear is we can't have it until we have eliminated corruption. In that industry it can lead to a literal nuclear meltdown.

You have to make the construction process transparent and verifiable enough and then these issues can be removed. It's not a given, but it certainly is doable.

> It's no longer cost competitive, and places like China that adopt a "let's try everything and see what works best" approach have heavily pulled back on nuclear.

When it’s night in Germany, it’s night in the rest of Europe.

When there is no wind in Germany, there isn’t usually much more wind across Europe.

Please take some look at actual electricity generating data for Germany (see smard.de) and find out why your assumptions are not correct.

You should have a look at the relevant literature. There have been several calculations made on how much overprovisioning is needed to run the grid only on wind, hydro and solar. It is significant but doable.

Also have a look here https://www.windy.com/?46.529,20.479,4 and look at the variation across Europe, especially if you include offshore wind.

I don’t foresee anybody paying for all this over built over provisioned solar/wind generation and transmission. I suppose if it has to be overbuilt 4x to be as reliable as the power system we have now then my power bill will be 4x more.

When people quote $1/W for solar generation it really should be $4/W because you have to build 4x as much and then add another ... infinite amount for increasing the size of the transmission system by 4x too so that areas that have sun can transmit to areas that have none. All possible just expensive.

>If your grid covers a large region

Like a belt of solar panels around the equator? Works for Dyson Sphere Program but that's a game. As big as the US is, for CONUS the entire continent is in the dark for significant portions of the day. It doesn't get more intermittent than that!

> and you have sufficient transmission,

Well duh. And assuming zero transmission loss. Or enough resources to overcome transmission loss and still be economically viable.

Quite a bit of hand waving there.

If I were in Texas last week, I would have loved to have a home solar system with a battery that let me island from the grid. This is definitely practical and happening even at today's high prices.

In a decade, ERCOT will look nothing like it does today. It will have massive amounts of solar and storage, and even more wind. This is replacing gas plants as they age out.

A buddy of mine has solar panels. During the storm they got covered in ice and snow, and generated about 180 watt hours in a 24 hour period

This is not a typical experience, from what I've heard. But for exceptional cases, in addition to fixed storage in our homes, we should be able to use our EV batteries for items of exceptional need, as they typically can handle 3-4 days worth of energy needs.

You would think that but some municipalities like New Orleans are addicted to the franchise taxes from new gas plants and roll over for the utilities (I am speaking about the South in general)

Will we actually need five nines out of renewables any time soon? We have the option of hanging on to old fossil fuel plants as emergency power for many decades to come. Peaker plants already perform a similar sort of role.

Our CO2 goals won’t be compromised by running emergency power off fossil fuel once every decade or two.

keeping old fossil plants sitting idle but in working order is possible but will cost nearly as much as generating at full capacity, minus the cost of fuel.

Imagine a car that sits in a garage and once a decade you take it out and thrash it. Machines degrade just from time not necessarily wear as rubber and gaskets become brittle, metal rusts, capacitors leak, fuel degrades, algae grows, rats chew on whatever they can, shafts and bearings and motors seize or get flat spots from sitting.

Look at Texas and their fleet of plants that didn’t start when they were needed. Any machine that is not running is likely to stay not running.

How about not having five nines, and just finding a way to live within that envelope?

Yep. Cheaper than all of this is having a few blankets, a camp stove, and a week's worth of rice and beans on hand.

Potable water, flushable toilet, heat insulated pipes.

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