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Comment by steve918 | Hacker News Reader

There are a lot of ways to generate lots of power, what we're generally lacking is ways to _store_ power to handle things like peaks.

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We know a lot of ways to store power. The trick is storing it efficiently. If we have enough surplus power (which may be the case in a few years), efficiency becomes less important.

Just as an alternative to prioritizing storage (we should still do it, but it's not the only constructive use), we could use a lot of excess electricity to create hydrogen, desalinate sea water and pump it inland, create biochar without kickstarting the heating process via combustion, etc.

The hydrogen could be used for hydrogen vehicles and other purposes. Seawater desalination (very partially) addresses sealevel rise while also getting water to dry areas. Biochar sequesters carbon while helping more plants to grow with less water and less chemical fertilizer.

So from a certain point of view, the above pursuits are like investing most of your "excess money" in the stock market rather than putting most of it in a savings account. And since we're starting to address climate change so late we need something better than just a savings account or battery.

Imagine a san Joaquin valley that feeds everyone/doesn’t lie fallow, and yet the rivers run free, and the delta smelt can live. Oh and California’s native salmon runs come back.

The difficult part is storing it on the kind of massive scale required full stop. Sacrificing efficiency can only do so much to help solve this, especially since the wasted energy has to go somewhere and dealing with that has its own costs...

A lot of these problems solve themselves with proper pricing. For example if power is nearly free during daylight hours and expensive in the evening, businesses will shift some percentage of energy intensive operations to daylight hours. EV charging stations will charge more during evening hours.

Charging EVs during daylight hours while they are parked at work places instead of overnight at employees homes is another way we can shift use. Some of these things might be done via pricing, others perhaps government incentives.

Storing power doesn't seem like an intractable problem. With the huge incentives with the coming electric car market, technology, renewables storage and god knows what else, I imagine there will be a lot of investment pouring into solving this. It's only a matter of time.

Well if you generate enough excess power, you hardly need to store any.

This makes no sense.

Without storage excess power is useless at best, dangerous at worst.

Now you shifted the problem to power transmission, because there's no way to generate an excess of power at all times in all locations using just wind and solar.

So while in my region at the time of posting this, 100% of electricity is generated by wind, there'd be 100% less if there was no wind (which happens from time to time).

Solar wouldn't help either, because right now it's dark outside and it will stay dark for another 6 hours.

So right now, even if there's an abundance of power generated elsewhere, it would have to get transmitted efficiently to here (and from here to where it's needed if applicable).

Local storage and massive interconnected power transmission capacity is what's required. And that ain't cheap.

My point is that if you have enough of something, it stops mattering as much how efficient you are with it.

Unfortunately no. Whatever power you generate you have to send somewhere. Excess generation will push the grid frequency high and destabilize the grid in much the same way that insufficient generation will pull the frequency down and destabilize the grid. Storage doesn't just provide power during low generation, it provides somewhere for power to go when generation outpaces demand.

This doesn't sound right.

With solar a small solidstate relay can disconnect individual panels as required, or a larger relay can disconnect strings of panels.

I was replying specifically to the "It doesn't matter if we just make enough" idea. For solar panels on a site scale you can use variable pitch panels focused on a solar collector to control your output power if you are peaking to high. Wind can use variable pitch turbine blades. Both of these configurations add a lot of cost but are worth it when talking grid scale generation and aren't uncommon in practice. The actual power you put onto the grid does need to be matched to how much is being used. Storage (hydro is the most popular it doesn't have to be batteries) allows for cheaper generation because you have a lot more options for burning off overshoots and peaks with the benefit of smoothing out dips. Without storage all of this together gives rise to weird things in practice like California selling power at a loss to Arizona and then buying it back because of the combination of subsidies and grid stability.

If generation outpaces demand enough and there's nowhere to put it, can you not just send some to ground? Or reduce your generation?

Consistency is the reason to store, not amount. The sun doesn’t shine at night and the turbines don’t spin without wind (which also is more likely at night). Modern society is built on always available electricity, and some things absolutely require them (eg a data center).

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