UK sees longest period of negative power prices

The Grid is excellent. I learned about it from Bill Gates' reading list.

Bought the book, but spoil a little for me if you would: I know that some utilities turn on pumped hydro storage to handle excess capacity, but what other ways are there to efficiently waste energy?

I wonder if we will ever get appliances that respond to the grid, a freezer that drops its temperature a couple of degrees because energy is cheap or a washing machine that waits an hour because it is expensive.

I suspect there is quite a bit of personal demand that could be shifted easily.

Someday, there will be a topic on HN about which I too am knowledgeable... someday.

You could even go so far as to have a bank of batteries, be paid to take in power, then earn money selling it back to the grid later when prices are positive.

You could mine bitcoins :)

It is a signal to ramp down or if you have a storage facility store.

If the prices remain negative or low for long periods it is a indicator to build transmission to where prices are high. Or if yours are a consumer build you factor or data center in the zone with low prices.

Perhaps not just when prices are negative, but it's not an uncommon practice to 'store' power by pumping water uphill when it's cheap and demand is low (generally at night), and then using that potential energy to generate and sell it when electricity is more expensive.

I have absolutely no clue what it would take to make that profitable, but it's a strategy for handling the natural spikes of demand when using power generation methods like solar and wind that are unable to adjust quickly to changing demand.

While the utility of electricity for consumers may become zero, transport of it via the grid still costs money. So for producers the electricity price becomes negative.

Power traders do this all the time. Each power plant/wind farm/solar farm has a generation cost and a time span that is required for startup or shut down. Balancing these factors and meeting demand the cheapest way possible is their business.

Also keep in mind that the price to consumers will never be negative. This would be only the generation and distribution side of the house.

Aluminum smelters already do exactly that. They use power no matter what, of course, but are well-positioned to be able to absorb massive amounts of electricity when the cost structure makes it beneficial to do so.

That's what energy storage is.

Another concept is "dispatchable load". With fuel-driven generation, you have dispatchable power -- additinal generating capacity is brought online to meet anticipated demand.

With dispatchable load, some process which can be rapidly activated or deactivated with little loss in overall efficiency is utilised. Examples would be water pumping (simply for water storage, irrigation, or other uses, not pumped-hydro power storage), or aluminium smelting, or electrically-driven thermal or reduction processes.

An equivalent concept is "make hay while the sun shines". The Sun's power isn't dispatchable (though it's fairly predictable), and if you're doing something that relies on it, you're best advised to make use of it whilst you can.

There's a facility in Switzerland which does exactly that: http://www.alpiq.com/news-stories/media-releases/media_relea... It provides "negative balancing energy" and turns water into steam.

If you own a large building or campus, you can get an ice maker to integrate into your HVAC system, and exploit electricity price dips. Thenwhen juice is pricy, you're just running air past your stored ice instead of running the AC.

The one catch is if you want this, you essentially have to let the utility control your system over TCP/IP

Yes. Modeling the load on the grid and anticipating supply/demand is basically what energy commodities traders do.

If you can provide superior guesses about prices, then you'd have traders lining up to buy your service.

I'm thinking that'd be a stretch. Anything that would sink enough power would have high capital costs, and negative prices (in my experience in US power markets) don't occur all that often. If you tried this as your primary business model, you'd wind up with a lot of money sunk in assets that may or may not pay off (and if they do pay off, will happen indeterminately in the future).

And you can watch at home: http://www.caiso.com/pages/pricemaps.aspx

Time to install some slightly obsolete bitcoin miners...

So then pump water up a hill during times of excess and then use that stored energy to spin turbine generators during times of need. just because it's supplying "too much" energy at one time doesn't mean it's not something that could be used effectively with the right infrastructure.

I have two qualms about this claim: The first is purely economical. Does this not simply indicate that there is insufficient supply of electricity storage (ie batteries)?

The second is... wow, if excess supply of energy is a reason there are detractors to wind and solar, then maybe treating electricity as a market is totally misaligned with perpetuating sustainable human activity. Maybe we shouldn't do that.

Sounds like someone needs to have better planning and buy a few extra batteries.

And hopefully to be ideologically consistent, these detractors have the same problem with coal and nuclear where it's more expensive for them to shut down and restart than it is for them to keep running and pay the negative price.

Oversupply is easy to burn up -- as long as there's robust and quick mechanisms for signalling when oversupply is going on.

There's plenty of loads that can be quickly spun up -- transferring workload from one datacentre to another is possible, as is running refrigeration systems to generate ice (or some other phase-change material) that can be used up during peak demand.

Anything remaining can be taken care of by bespoke energy storage systems, like batteries or pumped-storage.

Oversupply is only a temporary problem. When long distance transmission lines to other countries have been built, energy can be transferred across the continent to where demand or available storage is.

Inefficient usage, not pricing

Demand for extra power manifests as a drop in frequency not voltage.

Theoretically yes, though I guess the details are a little more complicated (depending on who exactly bought the energy and under what terms). e.g. energy company x might have bought all the capacity from wind farm y for the next 10 years, so then the fact that it's producing excess energy at that point in time becomes x's problem rather than y's. Presumably x would factor stuff like this in to their purchasing decision, so as long as the average price remains above some level they will still make a profit.

Or bitcoins will simply be devalued, and lose buying power until electrical demand changes or all of the last possible bitcoins are finally mined into existence.

Still need to maintain the grid, that isn't free.

Not realy. There are TWO markets for electricity. One is the Day Ahead system, where producers and consumers agree on who runs what generators and who consumes how much, in 24 hours.

The real time market, meanwhile, covers who it is who has to adjust his production or consumption to cover the difference between what everyone thought would happen 24 hours ago and what happens now.

The real time price hits negative, but it's only the delta between real time volume and day-ahead volume that's traded at the negative price.

And it's the people who are turning knobs, being paid by those who are sticking to what they planned to do at the Day Ahead market.

Sigh. This gets posted so many times.

There are no negative prices.

Here's how it works: Generators put out bids for how much they can produce and the price. Consumers pull in the bids ordered by price until they have enough power.

After that they pay everyone the highest price for the power.

So making your power negative just means you want to be first on the list.

You don't actually get paid negative money. It's just a tactic.

You could think of the problem in reverse: there's an excess of energy and they need to pay people to get rid of it (because using that much energy isn't as easy as dumping it in the ground).

If you could find a good way of getting rid of a lot of excess energy (worlds biggest kettle?) then you could potentially make a bit of a profit! Until someone comes along and finds something useful to do with the energy...