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Comment by ph0rque | Hacker News Reader

This tells me that until fossil plants are mostly shut down (and perhaps afterward), we will continue to have negative electricity prices at times. It might be a profitable idea to buy extra energy storage capacity to get paid for storing energy at certain times, then sell it when it is high demand.

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I just wish the negative electricity prices reached the non-industrial consumer.

If it reached me, I'll have an Arduino controlled hot water heater, furnace and fridge/freezer dynamically turning on/off to take the most advantage of prices pronto.

In some areas you can buy electricity this way, but the other end of the deal bites you, so beware of that.

When it seems like you might die from the heat but the price charged is $8.50 per kWh how much longer do you want to wait before switching on the AC? (If you live somewhere it never gets hot, figure on the same but for a midwinter freeze and deciding when to pay for your resistive circuit heat pump boost)

I figure it all averages out. But when I pay an average price, I have no incentive to lower demand when prices are high or raise demand when prices are low, contributing to even higher average prices.

There’s an Australian startup that sells electricity at wholesale prices to consumers

https://www.amberelectric.com.au/

It's all up to the charging algorithm. If your grid access is priced according to energy transferred, you pay a positive retail price no matter how negative the wholesale price is. If your grid access is a fixed charge, you could directly take advantage of the negative wholesale price.

In some places, industrial users have the second algorithm.

Reality is that grid access (transport/distro) should be more variable too.

Line sag is worst when demand is highest or it’s hot outside. Same with running out of transformer capacity.

When an upgrade is triggered, it’s to build more peak capacity.

Profitable for the first guy. Not profitable for anyone after enough people try to get a piece of that action. And maybe not profitable for anyone ever if the power company themselves installs enough storage capacity.

Yup, storage just like that has been built in Switzerland: https://www.alpiq.com/power-generation/hydropower-plants/pro... California is mountainous enough to follow suit.

California has a lot of storage just like that already. The problem is that it can't be scaled up.

California is beginning to dip its ties into battery storage, however. There's a couple projects that total about 200 MWh currently, IIRC. And at Moss Landing they are installing more than a GWh soon.

It's already cheaper to use batteries than natural gas peaker plants (the most expensive form of energy). The next phase of storage is to defer or replace transmission like upgrades (which are also super expensive). After that we get into daily cycle operations like giving small amounts of dispatchability to solar or wind projects.

And just like solar, batteries are getting cheaper far far faster than anybody ever predicted. What people used to consider the absolute floor in terms of raw material cost For lithium ion batteries is dropping all the time too.

However, the challenge for scaling up renewables and storage is not technical, it's going to be political. Utilities are not typical businesses that will just switch to the cheapest way of doing things. They are excessively political, and lobby a ton in order to influence how they are regulated (and thus how they profit off a captive audience), and they have been close bedfellows of fossil fuel interests for a loooong time because their combined lobbying power is so much stronger.

Oddly enough, just as hydro won't be able to scale even where it makes sense because of popular political opposition, we won't be able to scale renewables and storage because of entrenched interests lobbying Against popular opinion (renewables are popular across all of the political spectrum).

The only reason renewables would cause negative prices is the subsidy they get on generated output, that would cause them to continue generating because for THEM they are still making money at that instant. Otherwise, the renewable source itself could capture the negative price by just not feeding power to the grid.

Although I guess they "burn" their excess on-site, doesn't it make sense for solar panels to send power to a load at all times?

If they didn't, wouldn't that unspent energy make the panels even hotter and shorten lifespan/reduce efficiency?

It doesn't make sense for them to be sending power to the grid if they earn negative dollars doing it.

No, there's no cost to just not drawing power from the modules. They would become slightly hotter, but that's not a big deal.

I mean, if they're 20% efficient, then shunting the energy would mean they have 4/5ths the energy getting turned into heat, no?

In the US southwest, where it's the hottest here, most new utility-scale PV is using single axis trackers. So curtailment there could mean turning away from the Sun.

Dumping power is not free - you need properly cooled resistor banks etc. to do it safely. For many forms of generation it's worth putting power on the grid at negative prices under some circumstances.

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