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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

#151

Post by logfromblammo »

tantalor wrote: post #118
CapitalistCartr wrote: post #71

I wonder if there's a way to remove CO2 from the air with surplus electricity without a half-billion dollar plant. That would be a win for everyone. It operates when the wholesale price of electicity drops below its threshold, perhaps only 4-6 hours per day, so would have to be a pretty cheap fixed cost.

Yes its called a grow light they cost about $7 at home depot. It doesn't matter what you grow; weeds will work.

A bioreactor full of algae is a bit more efficient. You can even pump CO2 exhaust from your power plant directly into it.

Then you can sell the glop.

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

#152

Post by DoctorOetker »

amluto wrote: post #74
DoctorOetker wrote: post #53

Earlier quoted context omitted.

I thought they used electricity to deionize salt water, the salts are already dissociated into positive and negative ions, so pass a current through the water, and every now and then raise the electrodes out, mechanically scrape it off or reverse current in dump brine to remove the ions...

Doesn’t work. By the time you’ve moved any non-negligible amount of ions, you’ve built up an insane amount of charge and hence voltage. That voltage will be impossible to work with, not to mention many orders of magnitude higher than the voltage needed to split water into H2 and O2. One mole of singly charged ions is ~1e5 Coulombs. At an insanely high capacitance of 1 Farad (which you’ll never see in such an applicat…

I was thinking of https://en.wikipedia.org/wiki/Capacitive_deionization

I was wrong about the desorption step, I thought they scraped the ions off...

Incidentally at that page: "Part of the energy input required during the adsorption phase can be recovered during this desorption step. "

With enough of those electrodes, can't we use the sea as a big electrolyte battery? the energy is storedd capacitively

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

#153

Post by mercutio2 »

docker_up wrote: post #96
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.

Current furnaces do. But what if you changed the manufacturing process as well so that maybe the yield isn't as high but it's essentially "for free" in terms of electricity?

What you’re proposing is synonymous with “let’s make unobtainium with our spare electricity!”

If we could make anodes which weren’t destroyed by falling to a low temperature, we’d already be doing it.

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

#154

Post by DoctorOetker »

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.

I know of at least one pumped storage dam in Belgium, in the mountainous southern part (Wallonia)

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

#155

Post by logfromblammo »

Firerouge wrote: post #50
dev_dull wrote: post #10

The logical next step is devices (storage) which can arbitrage these prices and make a profit. Capitalism is a wonderful thing, especially when it’s helping make green energy more efficient.

A power wall that's paid to be charged during peak generation, and gets paid again to discharge during peak consumption would be pretty fantastic.

Why would a power utility allow customers to perform time-of-day arbitrage when they could do that themselves without upgrading all the meters?

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

#156

Post by theptip »

DoctorOetker wrote: post #120
woodpanel wrote: post #87

Earlier quoted context omitted.

> In the long run it should pay itself back. So in financial terms wouldn't this mean a rather weak profit margin? Plus the relatively high-risk that flood energy might not always result in free or negative energy prices gives it a bleak risk-to-profit ratio. In other words, there would always be something more utilizable to be done with excess energy (e.g. mining bitcoins etc. and buy water with it when you need it)…

Right, I explicitly mentioned not really believing desalination to be a good example, I was using it more as a fake illustrative example. In hindsight I should have ended with posing the following question: how do we make a simple guide for factory/etc operators/consultants to recognize such steps in their production line? Desalination is a bad example, because you need a complete new plant, while it is conceivable t…

I think the core of your idea would work well in theory; a much simpler example would be heating water, which both residential and commercial buildings do quite a lot. Once you have hot water, you can keep hold of it for quite a long time in a properly insulated tank.

Or at a higher level of abstraction, instead of us trying to figure out which "energy dense step" is the right one to target, instead the grid can provide a real-time price signal that flexible loads can use to get a cheaper overall rate by selectively turning on when the demand is lower.

This stuff is pretty well discussed under the umbrella of "smart grid" technologies: https://en.wikipedia.org/wiki/Smart_grid#Market-enabling

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

#157

Post by mattmanser »

true_tuna wrote: post #131

Here’s a crazy idea. Batteries? https://cleantechnica.com/2018/08/06/analysis-reveals-that-w...

They can't magically make national grid grade batteries overnight.

So, yes, at the moment it's a crazy idea. The whole point of the trials in Australia and places is to get it to work at the scale needed.

You can't just plug in 1,000,000 rechargeable batteries and hope it works.

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

#158

Post by Latteland »

nostrademons wrote: post #85
rwcarlsen wrote: post #68

Earlier quoted context omitted.

Neither of the alternatives you propose are what we currently have or are where we are currently heading (IMO). As long as we are speculating - I think a future with good storage tech and 100% solar+wind would be better than one with gas plants thrown in the mix. If climate change is as big a deal as people claim, than why would we sacrifice existing non-carbon-emitting capacity for natural gas? We don't currently ha…

The article suggests that solar + wind with natgas for peaks is exactly where we're headed. At least in the regions being talked about (mostly Europe + California). The Forbes article you linked is about New England. New England will probably be the last region to get decent renewable adoption. Solar panels don't work as well because they're far north and get a number of cloudy days, the winds are not that strong out…

I think battery storage peaker plants are where we are going, like the one in australia that tesla built.

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

#160

Post by nothrabannosir »

matthewmcg wrote: post #148
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…

Interesting thought. In Richard Rhodes new book Energy , he describes how an early iron smelting works in England, faced with temporarily low demand due to a recession, rolled its excess iron into railroad tracks which could be re-used for other purposes once demand recovered: Richard Reynolds, who managed the Darbys’ Ketley ironworks, near Coalbrookdale, in the 1760s, introduced cast-iron plates and then cast-iron r…

For mobile users:

Richard Reynolds, who managed the Darbys’ Ketley ironworks, near Coalbrookdale, in the 1760s, introduced cast-iron plates and then cast-iron rails to protect the wooden rails from wear and tear or to replace them. He had another reason as well for using iron: as an ingenious storage system. A depression following the end of the Seven Years’ War in 1764 reduced demand for iron products. Prices fell. Reynolds wanted to keep his furnaces going and his employees at work. Rather than warehouse the excess production, Reynolds used it for rails. Then, if iron prices went back up, he could have the rails removed and sold. Reynolds “tried it at first with great caution,” his granddaughter recalled, “but found it to answer so well, that very soon all their railways were made with iron.”

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