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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

#161
post #65

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.…

I wonder if a less efficient desalination plant would be cheaper. The modern efficient plants use RO with pressure exchangers, I think. Maybe a flash distillation plant or an RO plant without pressure exchangers would be economical to operate intermittently. But desalination may be a poor example in general. It’s not actually very energy intensive, at least compared to the value of potable water in an urban location.

Yeah, if I was gonna build a desalination plant built to use Just a big resistor in a big tank (or pond), a big fume hood and coil to another tank. Capital cost can probably be minimized a whole lot.

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

#162
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…

You hit at an important dimension which is that the problem is not technical per se, it's really a problem of market design. Wind power purchase agreements should allow curtailment (since it is very easy to ramp a wind farm /down/) when needed for system reliability. However, this reduces the rate of return for wind farms so politicians that are looking to maximize wind build-outs will not favour this. It's also bene…

We already have a mostly-unified central European power market. IIRC the whole central Europe grid is in a single market. Also note that providers with international transport capacity can use that to arbitrage over them.

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

#163
post #124

Earlier quoted context omitted.

If you wait for power prices to be negative (or merely lower than usual) you are not getting an economic return on the money you put into the desalination plant when it is not running. Think about it, if you get a 100M Euros loan to make a desalination plant, how long will it take to pay that off if you only run your plant a few hours per day vs 24 hours per day. Whether it makes economic sense depends on the differe…

Yes, hydrolysis could be a good solution. Create hydrogen and oxygen. The hydrogen could also be used in hydrogen cars that we have been talking about for decades.

[deleted]

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

#164
post #136

Earlier quoted context omitted.

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…

Regarding the cloudyness... Has anyone ever tried to levitate photovoltaics into the stratosphere? Blimpy-space-elevator kinda thing? Is such a thing even possible?

I feel like it's far easier just to transmit it 1000 miles or so from a sunnier place.

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

#165

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.

You'd probably be better off with water pumps to put water back behind a hydro dam. If you assume the presence of hydro, it's a pretty cheap battery to lift water back up.

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

#166

Earlier quoted context omitted.

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 cited natural gas being used for baseload power. In the last several years, gas has been installed frequently as baseload generation. All I'm saying is that I think governments' approaches to incentivizing energy production are very suboptimal for mitigating (negative) effects of climate change. And negative energy prices are one of the red flags that this is the case.

FWIW, my understanding is that the bulk of the baseload natural gas plants are being installed as replacements for older coal plants that are being decommissioned.

Considering that the latest project to construct new nuclear plants in the USA nearly put Toshiba - like, the whole company, not just their power plant division - into bankruptcy, I'm not certain, on purely economic grounds, how realistic an option "more nuclear" is.

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

#167
post #65

Earlier quoted context omitted.

I wonder if a less efficient desalination plant would be cheaper. The modern efficient plants use RO with pressure exchangers, I think. Maybe a flash distillation plant or an RO plant without pressure exchangers would be economical to operate intermittently. But desalination may be a poor example in general. It’s not actually very energy intensive, at least compared to the value of potable water in an urban location.

Yeah, if I was gonna build a desalination plant built to use Just a big resistor in a big tank (or pond), a big fume hood and coil to another tank. Capital cost can probably be minimized a whole lot.

You can use sun light directly for that. Just paint your boiler black, maybe concentrate some sunlight with cheap mirrors.

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

#168

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…

There are a lot of interesting Demand Response solutions that are also somewhat applicable/useful for this problem.

In a normal demand response scenario, when too many people are demanding energy, certain loads are turned off or scaled back (ACs/Thermostats/Water Heaters).

Water heaters in particular have been shown to have been one of the better time shifting solutions. Seems like you could do the same thing with both water heaters and AC systems as most buildings have quite large thermal masses. For AC its a bit lame because the hottest time of the day is the best producing for PV frequently so shifting can be tough, but perhaps around the beginning of the day and end of the day there is some opportunity to precool homes before people return and then back off as the price goes above 0, that sort of thing.

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

#169

Earlier quoted context omitted.

Yeah, if I was gonna build a desalination plant built to use Just a big resistor in a big tank (or pond), a big fume hood and coil to another tank. Capital cost can probably be minimized a whole lot.

You can use sun light directly for that. Just paint your boiler black, maybe concentrate some sunlight with cheap mirrors.

Yea but not at night.
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