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Comment by shoguning | Hacker News Reader

Maybe I'm missing it, but I don't see an indication of how much storage they are talking about here. The problem with renewables is still intermittence, and geographic dependence. Solar does no good at night, and there are days the wind doesn't blow. The costs of storage for that bulk application still don't seem to make sense, and I don't see it addressed here. The Tesla battery replaced power on the order of seconds, which is still a success, but not enough.

In general, solar has been great for reducing peak demand, since it has highest output during the middle of the day when electricity demand is also greatest. Not clear how much farther it can go, though. Wind may be able to replace some, but wind isn't strong everywhere.

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"Solar does no good at night,"

There are already several thermal storage solar facilities in operation, with more under construction. The best of these can maintain output all night long. One is in Spain, one in Australia, a prototype I believe is still operational in California.

Taking a single family home off grid using slightly over sized solar and batteries is already cost competitive in most areas.

The real question is if economies of scale and the ability to shift demand across geographic areas offsets the cost of an electric grid + administrative overhead. Based on the constantly increasing rate of Solar deployments I can only assume this actually works out just fine.

> Taking a single family home off grid using slightly over sized solar and batteries is already cost competitive in most areas.

What areas? I've checked a few and it wasn't remotely close.

It starts being doable if you are willing to do things like load shed during the night - but I'm not. The goal would be for a zero impact on my lifestyle storage system (e.g. multiple days of storage for A/C use during cloudy/stormy weather, no 'no laundry days', etc.) and that simply isn't realistic yet.

I find this important since when I do go off-grid, I think it's immoral for me to expect the poorer folks who can't afford such equipment to subsidize my free battery by keeping an "emergency" backup connection like pretty much all "off grid" folks I personally know. Yes, it gets real cheap when you don't have to size for an expected worst-case - but that's not very interesting to me.

That said - some of the DIY hacker style projects are getting rather close. It's very tempting to start looking for a couple old Tesla battery packs and the like these days and go it alone. If that's the case, I expect within 5-10 years it will actually be doable commercially off the shelf.

First a backup generator is a lot cheaper than a backup grid connection for the next 20 years. Now, some would look at that as an extra cost, but IMO most homes should have an undersized backup in case the grid goes down anyway.

Next installation costs quotes are often insane, but basic equipment costs are not even close to that. A ~10KW system for ~1,600 kWh/month as a reasonable off grid system that's well above most homes normal usage levels and depending on battery power that should be well under 20,000$ before government incentives.

Now, you can start running the numbers on payback periods and whatnot, but it's close enough you need to consider your local rates not just dismiss it out of hand. Sure, you could use fewer panels but panels are only ~1/3 of the system price so no need to scrimp on them.

>I don't see an indication of how much storage they are talking about here

The final figure shows storage at various MW sizes for 4 hours, 8 hours, and 10 hours.

That said, we have almost no information about this bidding process, so we can't read too much into it.

But once you take into account that these are for projects that enter service in 2023, it makes a lot of sense. By then lithium ion batteries will be less than half the cost they are right now.

Vanadium prices have also been skyrocketing, so its likely that vanadium redox flow batteries may reach industrial scales by then, and could be as cheap or cheaper than lithium ion.

Electric demand is greatest in the evenings when people return home from work, cook, etc.

Solar production is greatest around midday. There is a lag time of about 6 hours between greatest production and demand, and the storage systems are designed to accommodate this.

So I gather you don't believe batteries will succeed as a solution

Not clear. If costs really continue to decline, batteries will make up a bigger and bigger part of the solution, but costs and uncertainty of the massive scale battery projects still seem high to me. Decreasing demand, nuclear, carbon capture, batteries, etc will all play a role IMO.

Carbon capture seems like a bigger wildcard to me than battery technology. Battery technology has been improving pretty steadily and will likely continue to do so.

Capturing carbon from coal power plants adds cost to something that is already not cost effective. Capturing carbon in the atmosphere likely will require huge amounts of power - and if its not 100% renewable power its kind of pointless.

Nuclear is better than coal or natural gas, but there have been some high profile failures lately and the lead time on new nuclear is so high, as well as the sticker price.

Nuclear and coal are available now and are known to work. Utility-scale battery farms of the magnitude necessary are not.

>Nuclear and coal are available now and are known to work.

Nuclear is not available now in the sense that you can order a plant and have it running in a year or two like you can with solar. More like a decade

Coal is available, but more expensive than natural gas. Coal is dead, did you really not know that?

>Utility-scale battery farms of the magnitude necessary are not.

But rapid progress is being made, and the utilities are planning for the future, which is only rational.

>Nuclear is not available now in the sense that you can order a plant and have it running in a year or two like you can with solar. More like a decade

The interesting aspect is that by the time a nuclear power plant is online renewable energy and battery storage might have advanced enough to make it uneconomical.

OK, so how long do you wait? How sure of a thing do we need? By that logic we wouldn't do anything. Do you think coal got started with a sure thing?

How is it we're more concerned with wasting some money than the possibility of catastrophic climate change? This is why the federal government should be more involved with combating climate change - nobody is willing to risk their money, or their power bill going up, even if it means essentially saving the world and/or our way of life.

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