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Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

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Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#321

Post by ForHackernews »

eloff wrote: post #236
floatrock wrote: post #48

Earlier quoted context omitted.

Capital costs vs. marginal costs. You're going to build a $100M desalination plant and run it for three hours a day? That's a ton of money sitting idle most of the day, far more than what is recovered with zero operating costs. (This is called the utilization factor -- how long a piece of equipment is used vs. staying idle) Ideally you want useful processes with low capital costs and expensive marginal/energy costs.…

Desalinization isn't a good example for the reasons you say, but theptip writes below that heating water in residential and commercial settings might be better. Since water once heated stays hot for a good while in the insulated storage tank. Also buildings can be heated with hot water instead of forced air, typically through pipes in the floor. Which is nicer because it keeps your feet toasty and doesn't dry out the…

Storage heaters are common in many parts of Europe: https://en.wikipedia.org/wiki/Storage_heater

They already work on this principle, more or less: heat up overnight when electricity is metered cheaper, then discharge during the day.

There are several companies working on making "smarter" versions that can switch on and off in response to real time data.

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#322

Post by mprovost »

bacon_waffle wrote: post #283
ksolanki wrote: post #278

Earlier quoted context omitted.

This is insightful. The solution is probably to have a spot market for electricity that is accessible via an API so that smart AC or fridge or electric car charger can make use of it. This will encourage market for devices that can utilize the lower spot prices dynamically and keep the things more efficient overall (in steady state).

We've got these in New Zealand - once you have a "smart meter" (which I believe most homes now have), then you can pick an electricity retailer like https://www.flickelectric.co.nz that bills you according to the current price. Flick provides an API to allow you to turn on/off loads when you see fit.

Even before smart metres, NZ has had a ripple control system since the 1950s which sends signals over the electric lines to your circuit breaker so the utility could remotely turn domestic hot water heaters off during periods of high demand. The technology is pretty simple, you could reverse it to turn appliances on when power is below cost.

http://www.oriongroup.co.nz/customers/load-management-and-ho...

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#323

Post by yvdriess »

gamegoblin wrote: post #149
yayana wrote: post #98

Earlier quoted context omitted.

I think Pumped Hydroelectric Storage is what you are looking for. I've seen a few of them here in Switzerland. I think many were originally built out with the train system's grid for it's reliably scheduled low and high capacity times. http://energystorage.org/energy-storage/technologies/pumped-...

Does Belgium (OPs example) have the geography necessary to support pumped hydro? Your example, Switzerland, is significantly more mountainous than Belgium.

Wallonia has at least one pumped hydro that I know of.

There were plants for a 'energy island' 300MW hydro plant at sea, near the large-scale wind farms. The idea is the same, pump sea water up an artificial horse-shoe shaped island. A nice bonus is that you can play with the tides as well. The height difference does not have to be great, if you can compensate with a large surface area.

As far as I know, those plans were shelved. A quick googling says that similar concepts are being considered for interconnected dutch/danish wind farms.

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#324

Post by jasoncartwright »

fuzzbuzz wrote: post #310
undreren wrote: post #296

Earlier quoted context omitted.

> but theptip writes below that heating water in residential and commercial settings might be better. When I worked at Ørsted, we did this all the time . We had a huge electric kettle, which we used to produce district heating water. But there are many more things you can do with surplus energy. You can make methane gas from pure CO2 and hydrogen when you apply electric power as a catalyst. The methane can then be ea…

A banal long term way of storing energy is to pump water up to some high ground. Whenever you need it, use a turbine to get the energy back.

This is exactly how the 6th largest power plant in the UK works (but the turbine is reversed to become the pump)

https://www.youtube.com/watch?v=McByJeX2evM

https://electricityproduction.uk/plant/GBR1000151/

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#325

Post by undreren »

hvidgaard wrote: post #303
undreren wrote: post #296

Earlier quoted context omitted.

> but theptip writes below that heating water in residential and commercial settings might be better. When I worked at Ørsted, we did this all the time . We had a huge electric kettle, which we used to produce district heating water. But there are many more things you can do with surplus energy. You can make methane gas from pure CO2 and hydrogen when you apply electric power as a catalyst. The methane can then be ea…

I was at a tour of Skærbækværket many years ago, and as I remember it, when you produce power, you need to be able to control the voltage somehow. If there is a surplus of power and you cannot turn down production, you need to dump it or the voltage will go up, destroying electrical systems. One of the simplest ways to do this is to heat water, and when you have well established district heating it's almost a no brai…

It's a nobrainer, but the electric kettles are rather expensive and are usually therefore only bought to ensure production capacity in the case that the powerplant's own kettle malfunctions.

Besides, district heating produced on power from the grid is taxed as if produced on coal, as the power has no traceability. This makes it really expensive, unless you are directly hooked up to a solar or windfarm.

That's the law in Denmark at least.

PS: I worked in the administrative building just next door to Skærbækværket! :)

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#326

Post by Arnt »

floatrock wrote: post #48
DoctorOetker wrote: post #22

I don't truly understand this "problem". I understand storing the energy in batteries is currently very expensive economically and materially. However I believe there are plenty of "goods" (irrespective of if they are bulk materials, or partially processed products) which have a high processing energy per volume ratio (this does not need to be recoverable stored energy). Allow me to give an example: currently we have…

Capital costs vs. marginal costs. You're going to build a $100M desalination plant and run it for three hours a day? That's a ton of money sitting idle most of the day, far more than what is recovered with zero operating costs. (This is called the utilization factor -- how long a piece of equipment is used vs. staying idle) Ideally you want useful processes with low capital costs and expensive marginal/energy costs.…

Not hours per day. But if your climate has wet winters and dry summers you might choose to build a desalination plant that you only really need to run for three months per year.

And then you have the plant sitting there for most of the year, able to help the power grid. So the example makes sense.

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#327

Post by jmmcd »

rstuart4133 wrote: post #237
bluGill wrote: post #69

Earlier quoted context omitted.

Unfortunately it doesn't. Aluminum needs a lot of electricity, but it needs to be consistent for several hours. It takes a lot of energy true, but the furnaces need to be at operating temperature. You can't just turn them on and off, there are startup and cool down times that need to be accounted for.

> Aluminum needs a lot of electricity, but it needs to be consistent for several hours. Then Aluminium smelting is an excellent match for wind and solar. Quoting https://hal-mines-paristech.archives-ouvertes.fr/hal-0052998... "Typical numbers in accuracy are an RMSE of about 10- 15% of the installed wind power capacity for a 36 hour horizon."

If I understand right, that figure is measuring the accuracy of a prediction of electricity production, not the constancy of the production. We can't smelt aluminium with no power even if we have predicted that there'll be no power.

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#328

Post by bogomipz »

Kliment wrote: post #293
xigma wrote: post #88

Earlier quoted context omitted.

> Basically this is a problem because a bunch of existing incumbents are probably going to go bankrupt, or at least have to write down a lot of capital equipment and invest in new technologies. That's not how it works. In Germany, the government subsidizes farmers to put up Windfarms, then forces the electric companies to buy the electricity at an inflated price, which those companies charge their customers for. As a…

The coal terrorists are able to demand subsidies not because of their poor workers (they are in fact laying off lots and lots of workers as a side effect of mergers, and their total employment is just several thousand people) but because a lot of local government is funded by coal company shares held by cities. This is why coal is still a thing.

>"a lot of local government is funded by coal company shares held by cities."

Do you have a citation for this? What are examples of the many local governments that are funded by coal company shares? How do you fund a local government by buying shares in a coal company?

Coal is "still a thing" because it is incredibly abundant and despite being horrible for the environment, burning it is a thermally efficient means of creating steam to turn a turbine.

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#329

Post by kmc059000 »

eitally wrote: post #280
ksolanki wrote: post #278

Earlier quoted context omitted.

This is insightful. The solution is probably to have a spot market for electricity that is accessible via an API so that smart AC or fridge or electric car charger can make use of it. This will encourage market for devices that can utilize the lower spot prices dynamically and keep the things more efficient overall (in steady state).

Some electricity utilities offer this as a sort of service to their customers, where they detect high grid utilization days and notify customers they can save $ by reducing consumption on those days. Here's PG&E's page about their version: https://www.pge.com/en_US/residential/rate-plans/rate-plan-o... It's not "smart" or automated, but it's a baby step.

This concept is called Demand Response and is quite prevalent. Consumers receive a discount for reducing their load at peak times.

This frequently targets very high demand customers rather than residential for the simple fact that it's easier to ask a company to delay starting a single piece of machinery than to reduce the load on an equivalent but large number consumer appliances like refirgerators.

Doing this at a residential level will require significant costs to support at a residential scale. Technology is the key in solving this problem.

Re: Power Worth Less Than Zero Spreads as Green Energy Floods the Grid

#330

Post by swarnie_ »

talltimtom wrote: post #309

I find it funny that there is an ongoing discussion of how much electricity bitcoin mining wastes and another ongoing discussion of how to store free electricity. The answer is simple! Mine bitcoins when electricity is free and use the bitcoins to buy power when prices go up! I call the scheme cryprographic energy storage. I am current looking into creating an ICO at $10 billion valuation. /s

You've added a /s but some mad man is already pitching this somewhere in the valley and it probably being taken seriously
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