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Comment by nordify | Hacker News Reader

I get the arbitration angle, but doesn't it purely depend on there being a market failure, i.e. failure to match production to demand and/or grid failure to transfer power between demand imbalance regions?

Wouldn't the better long term solution be to fix the market failure?

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That's not how it works.

When a cloud covers up a solar panel, the region needs to grab energy from somewhere. When the wind stops blowing, the Wind Turbines require energy to keep them spinning (yes, during times of low-wind... wind power USES energy, not produces it).

It is very rare to find a stable source of energy. Nuclear and Coal are extremely stable, but the politics of those energy sources are poison to many communities.

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Note that the US uses twice as much energy during noon than it does at midnight. The only way this discrepency is solved right now is:

1. Energy storage -- store the energy generated at night to help out during the day. Nuclear and Coal power plants make just as much energy at night as they do during the day, so "storing" the excess from night will help out.

2. "Peaker" energy plants (Natural Gas can start and stop very quickly). But obviously, this is inefficient and wasteful.

Solar Panels sorta help from this regards, because they generate more electricity during the day rather than at night. But all Solar Panels will do in the long-term is shift the problem to 4:00pm when the Sun begins to set but electricity usage remains very high.

This isn't the case of "Kentucky is using more energy right now, pull from some Tennessee". This is the entire freaking US, simultaneously, uses double the electricity at one point in time, and then stops using it at another point in time. (A valid "load balancing" solution is to have night-shifts at factories btw. Not everything needs to be solved through technical innovations)

Finally, we have the issue of over-powering the grid. If the grid has too much power applied to it, it damages equipment. Energy storage can eat-up excess capacity on the grid safely and efficiently (and then sell it back at another time).

Energy storage is going on constantly under the modern grid. The US just needs more of it... we need more of it cheaper and in bigger amounts than ever before. Especially if we're going to start using unreliable sources of energy like Wind or Solar.

Given that it's never noon/midnight across the entire country, do you mean that at each point independently, usage is double at local noon vs. local midnight, or do you mean that there exists a single point in time where usage is double another point across the whole country?

If the former, if we had a better CONUS-wide grid, that could distribute power East/West more efficiently, how much would that help?

Each point independently, although the ratio can be as low as 1.5x during winter (summer air conditioning is a big problem).

East / West power distribution won't help too much, because there's only a 4-hour difference. The specific load curves of New England (which is only 1.5x load peak vs bottom at the moment... more typical of winter conditions) can be found here: http://www.iso-ne.com/

So, even in a prefect world, it all comes down to whether it's cheaper/better to overgenerate and store or to run peaker plants?

It seems storage has a long way to go as long as gas peaker plants are around 7c/kWh.

Energy storage is beating peaker plants today... under specific situations.

Note that gas peaker plants only run 10% of the time on the average (basically, they only work in the summer when our grid needs the most power, and then they don't make any money for the rest of the year).

From an economics / business point of view, having your power plants sit around only working 10% of the time is completely uneconomical. You need to be compensated severely to make it worth your while.

Or to put it another way: my energy storage company that gets 1c off energy arbitrage for all 12-months 100% of the year will make more money than your peaker plant that only gets 7c for 10% of the year.

And good luck convincing California to build a peaker plant. It is more politically sound to push for green-energy batteries. You'll get more approval in more locations in the US than gas (even if Natural gas is all-American and burns cleanly, its still a fossil fuel which is increasingly becoming a poison word in politics)

Your storage system must be able to store enough energy to cover the cumulative output of the peaker plant in order for it to be able to replace the peaker plant.

That's a lot of storage. And you need to have enough overgeneration to be able to reliable fill it up daily. This sounds very expensive. Could it really work from an economic perspective?

It already does work.

https://www.dom.com/corporate/what-we-do/electricity/generat...

This worked in 1970. Why wouldn't it work today? Energy storage solutions are deployed around the nation, and world, for this very reason.

The main advantage is that energy storage today is more efficient, with new technologies coming out.

> The main advantage is that energy storage today is more efficient, with new technologies coming out.

But not cheaper or anywhere close to the scale of pumped hydro?

Hydro requires favorable geography and/or rebuilding the grid to cope with the extremely large flows required to keep up with storage.

So, energy storage works, but is not economically feasible other than as research projects outside of hydro?

Looks like peaker plants are here to stay for a very long time.

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