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No Sun, No Wind, Now What? Renewable Energy Storage

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Re: No Sun, No Wind, Now What? Renewable Energy Storage

#31

Post by ncmncm »

mort96 wrote: post #13
ncmncm wrote: post #5

Somewhat disappointing... Would have liked for her to call out NRGV as the actual investment scam it is, rather than just pathetically inadequate. Would have preferred for mineshaft gravity storage to be mentioned, which is not a scam, in place of NRGV. Would have liked for her to cite ammonia along with hydrogen as chemical storage media. And to mention recent, radical improvements in hydrogen electrolysis efficienc…

> Disappointed that she brought up nukes without mentioning that they are wholly unable to compete with renewables, on cost. Is this true? I mean per average watt I imagine solar might be cheaper, but is it still cheaper when you factor in the cost of the energy storage you need to have a purely solar/wind grid? I'd love to see some numbers on this.

Cost for storage is falling even faster than for renewable generation.

Re: No Sun, No Wind, Now What? Renewable Energy Storage

#32

Post by natmaka »

credit_guy wrote: post #14

What if we don't need anything fancy? We can reduce our fossil fuel dependency by more than 90% if we switch to renewables, and just use natural gas plants when they don't produce enough energy. No need for any new storage. The current natural gas storage will be many times more than enough. But isn't natural gas bad? Doesn't it mean we still emit CO2? We can offset that with trees. And even if we don't, I don't thin…

France is (by far) the world leader when it comes to the fraction of nuclear-produced electricity and always produces around 9% of its electricity thanks to fossil fuel, because building enough reactors to satisfy peaks and to load-follow would be way too expensive (as most would be idling most of the time). 9% of a year is approximately 33 days, therefore we know how to cope with a Dunkelflaut. https://www.statistiques.developpement-durable.gouv.fr/editi...

Moreover a continental mix (wind, solar, geothermal...) reduces intermittency. Wind: https://www.imperial.ac.uk/news/180592/european-cooperation-...

Moreover modern gas turbines are able to burn (up to 100% of) hydrogen, therefore feeding them green hydrogen (obtained during over-production periods) will lower emissions. https://global.kawasaki.com/news_211209-2e.pdf https://www.get-h2.de/en/project-lingen/

Moreover storage has many gorillas in the room, mainly V2G https://en.wikipedia.org/wiki/Vehicle-to-grid

Re: No Sun, No Wind, Now What? Renewable Energy Storage

#33

Post by Lutzb »

realusername wrote: post #23
ncmncm wrote: post #7

Earlier quoted context omitted.

Nuclear is dead not because people are afraid of it. Nuclear is dead because it is way more expensive than alternatives. Always was, and getting moreso as renewables cost continues on down. In the foreseeable future, nukes will be mothballed long short of their design life just because nobody will want to pay enough for their power to enable continuing to operate them. Geothermal might suffer the same fate. When a nu…

It's only more expensive if you don't factor external costs due to renewables. At the moment, renewables still can't compete on pricing with 70s nuclear designs...

citation needed

Re: No Sun, No Wind, Now What? Renewable Energy Storage

#34

Post by lispm »

realusername wrote: post #22
lispm wrote: post #11

Earlier quoted context omitted.

a) there is a difference between electricity production and energy use. Typically countries don't use electricity for all energy needs. b) are you aware that half of the nuclear fleet in France isn't online? https://www.brusselstimes.com/belgium-news/274261/controlled... > It's clean, it's energy dense, and we can make a lot of it. France gets most of it's energy from Nuclear plants. It's not clean, since the nuclear…

Ironically, France has issues now because they spent around 120 billions on renewables with very few results. Had this money been spent on the nuclear grid, the gris would be in a much better state now.

They were not even able to finish one new reactor. The EPR is a decade late with massive cost increases. Why would anyone spend more money on that?

https://www.reuters.com/business/energy/edf-hopeful-end-sigh...

With more than half of the French nuclear fleet offline, nuclear in this energy crisis is just only contributing to the problems.

Re: No Sun, No Wind, Now What? Renewable Energy Storage

#35

Post by bequanna »

credit_guy wrote: post #17
bequanna wrote: post #16

Earlier quoted context omitted.

Sure. How many natural gas plants do you reckon we will need? Following your idea, it seems like we will need to replace almost all existing base load with a stable options like nat gas. But then why bother investing in these unreliable “sustainable” sources at all? So we can collectively pat ourselves on the back while paying much more for electricity? At some point, perhaps we should start asking why we are replaci…

> How many natural gas plants do you reckon we will need? Many fewer than we already have. Not sure I understand your other questions. What unreliable "sustainable" sources? Why paying much more for electricity?

Wind and solar are quite unreliable.

That's the dirty secret. Wind/Solar might be price competitive at some $/MWh but you need build MUCH more capacity to make up for how unreliable they are.

Each utility needs to purchase generation capacity in advance and it has to be enough to cover estimated peak usage. This is a regulatory requirement. I find it interesting that if the utility chooses to reserve wind generation, they can only apply 7% of the nameplate capacity (!)

According to that math, if we're going to replace current coal/nuke/nat gas base load with wind and expect some amount of reliability, we will need to build 14x as much capacity. That is just madness.

Interestingly, regulated utilities actually LOVE this because they make money for their shareholders by having some capital expenditure base amount. The Public Utilities Commission then allows them to earn some return on that base. I believe the allowed return is usually something like 8-10%. The more they spend on capacity and the less reliable the source is, the more money they make.

Pretty perverse incentives, but you're a luddite science denier if you at all question this scheme.

SO, if you have to waaaaay over build capacity because your sources are unreliable, the utility has to invest more to build that out. Their return on investment in generation then comes from YOU via much higher rates.

Re: No Sun, No Wind, Now What? Renewable Energy Storage

#36

Post by ncmncm »

mort96 wrote: post #13
ncmncm wrote: post #5

Somewhat disappointing... Would have liked for her to call out NRGV as the actual investment scam it is, rather than just pathetically inadequate. Would have preferred for mineshaft gravity storage to be mentioned, which is not a scam, in place of NRGV. Would have liked for her to cite ammonia along with hydrogen as chemical storage media. And to mention recent, radical improvements in hydrogen electrolysis efficienc…

> Disappointed that she brought up nukes without mentioning that they are wholly unable to compete with renewables, on cost. Is this true? I mean per average watt I imagine solar might be cheaper, but is it still cheaper when you factor in the cost of the energy storage you need to have a purely solar/wind grid? I'd love to see some numbers on this.

There are different ways to cook the numbers. In particular, there are different kinds of costs.

In nukes, capex (capital expenditure) absolutely dominates. That has to be amortized over all energy produced over the working life of the plant. Opex (operating expense) in nukes is also high in comparison to renewables', dominated by maintenance: overhauling steam turbines, inspections, repairs; and 24/7 staff and security. Fuel cost is low compared to coal, but far from negligible. There are hidden costs usually not counted, such as liability insurance always paid directly by taxpayers. Paying that out of revenue would price nukes' power completely out of the market, assuming any insurance company could afford to cover it at all. And there is decommissioning cost, a substantial fraction of capex.

If the plant is mothballed early because it cannot produce at a competitive price, its cost for all the kWh already delivered suddenly jumps because its capex can be amortized over only those kWh. Similarly, if it is operated only at night, its per-kWh cost doubles because it costs about the same per day whatever its output.

Usually existing nukes are compared to renewables with the nukes' capex, liability, and decommissioning costs artificially pinned to zero, but counting the full capex of the renewables, because those have to be built before they can produce. Renewables' opex is very close to zero.

Maintaining a big steam turbine is remarkably expensive. Nuke plants are built with spares because they spend so much time down for overhauling.

Re: No Sun, No Wind, Now What? Renewable Energy Storage

#37

Post by credit_guy »

bequanna wrote: post #35
credit_guy wrote: post #17

Earlier quoted context omitted.

> How many natural gas plants do you reckon we will need? Many fewer than we already have. Not sure I understand your other questions. What unreliable "sustainable" sources? Why paying much more for electricity?

Wind and solar are quite unreliable. That's the dirty secret. Wind/Solar might be price competitive at some $/MWh but you need build MUCH more capacity to make up for how unreliable they are. Each utility needs to purchase generation capacity in advance and it has to be enough to cover estimated peak usage. This is a regulatory requirement. I find it interesting that if the utility chooses to reserve wind generation,…

> Wind and solar are quite unreliable. That's the dirty secret.

It's not a secret, that's what most people say. But is it true?

Take a look at the graphs in [1] with monthly electricity generation by source in the US. You will notice that renewable electricity generation is a bit jagged, but not a lot. The ratio between the highs and the lows may be 1.3, but it's certainly not 7 or 15 as you imply.

The thing about 7% of the nameplace capacity counting towards peak availability is a red herring. Power companies can keep natural gas plants. Those are very cheap (about $1000/kw of nameplate capacity, on par with solar, but obviously without intermittency issues). They don't need to run them all the time, 5-10% of the time will be enough. Overbuilding renewables by a huge factor to supposedly be allowed to earn 8-10% is a nice conspiracy theory, but assumes they'll find people to sell to at a profit. When you generate many times what people consume, you'll eventually need to pay others to take the electricity from you (yes, negative prices are a thing in the power markets).

[1] https://www.eia.gov/totalenergy/data/monthly/pdf/sec7_4.pdf

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