this post was submitted on 23 Aug 2023
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[–] [email protected] 27 points 1 year ago (4 children)

Yes, because profit is what's so important and not part of creating the problem, right?

Why not use both?

[–] [email protected] 12 points 1 year ago (1 children)

Because we only have limited resources and they have to be used wisely. So if it is cheaper to build solar, rather then nuclear, we should use our workers to build solar. The other problem is that nuclear reactors do not last forever, so over time, they will be phased out, just due to economics.

[–] [email protected] 3 points 1 year ago (3 children)

The problem is it's not that simple from a climate perspective. Solar and wind are great but are incredibly variable which is not good when you need a guaranteed baseline electricity production. There is no situation under which a large nation could reliably just use wind/solar to power the country. Currently nuclear is the only renewable, clean energy source that can produce a stable output.

[–] [email protected] 8 points 1 year ago

Nuclear is not renewable. It uses uranium as fuel. It is low carbon and emission free, but not renewable.

There are two solutions to intermittency. First one is a large grid with a lot of differen renewable power sources. It is always sunny somewhere, so when you can move the electrcitiy around, you have much less of a problem. Even better ifyou have wind power as well. With a continent sized grid, you basicly avoid the problem of cloudy days.

Next part is storage. Due to the large grid size you have the ability to use hydro power plants with reservoir as long term storage for particullarily cloudy days or winter and battery and pumped hydro for nights. Biomass is also an option if need be. Maybe we later hydrogen as long term storage as well, for really bad weeks and using it mainly for say chemical plants. Again the better large and interconnected the grid the less storage is needed. In some regions namely large sunny deserts having a nights worth of storage and some emergency backup biomass power plants would be enough. Basicly it runs down to less then a day worth of storage

There are also actually renewable baseloads like hydro power for flow power plants and geothermal, which are also good options. Also variable demand is a thing, which allows for even more renewables.

Seriously intermittency is much less of a problem, then it is made out to be. You just have to add a bit of interconnection and storage to it, but even that is not that expensive and seriousyl usefull.

[–] schroedingershat 5 points 1 year ago

This is the lie that is told, but nuclear has trouble getting grid penetration over 70% even with massive overprovision and storage via foreign interconnect.

Stable output which is totally interrupted for weeks at a time isn't useful for meeting a combination of stable, variable, and dispatchable loads. Nor does it contribute meaningfully alongside variable output.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago) (2 children)

You and many people overestimate the effect of clouds on solar power generation. Even on cloudy days solar panels still produce mostly the same amount of power. On the absolutely darkest cloud days, solar panels still put out about 50% the same amount of energy they generate on perfectly clear sunny days. And that's only for the absolutely darkest cloud days, whereas if it's just a typical overcast kind of day the output will be a lot higher. So even if society went to being completely solar powered, you'd only need 50% more solar power generation to be completely meeting your needs even on the cloudiest days.

[–] [email protected] 2 points 1 year ago (1 children)

Isn't the issue more going to be the solar power generation during winter - which happens to also be when energy demand is greatest?

[–] [email protected] 1 points 1 year ago (1 children)

It probably depends on where you live, but from a quick web search i see sources saying most energy is used in the summer. ( https://learn.pjm.com/three-priorities/keeping-the-lights-on/how-energy-use-varies.aspx ). In locations that receive less sunlight you would simply need more solar panels to meet your needs. In those rare areas that truly receive very little sunlight for months you would choose other technologies like wind, especially since those dark areas likely correlate with where wind is stronger and steadier.

But my comment was in reply to the person who claimed that solar wont work when it's cloudy, which is false. Solar works great even when it's cloudy.

[–] [email protected] 1 points 1 year ago

Oh you originally responded to me but I never said anything about cloud cover.

[–] bouh 2 points 1 year ago

And Europe energy crisis last winter was partly due to unperfect meteorological conditions over Europe.

And solar panels produce zero energy during the night.

[–] [email protected] 3 points 1 year ago (2 children)

No reason to fight the tide. Renewables and storage are enough.

[–] [email protected] 3 points 1 year ago (1 children)

People just say "storage" as if it's some simple solution. It's not. Pumped hydro can work in some places but it can also cause pretty impactful disturbances for the local ecosystem so it needs to be planned with care. Hydrogen storage is not a mature technology yet, it's still in the trial stage and has pretty poor performance (something like 35% round-trip efficiency), not to mention the issues with hydrogen gas leaking due to its small molecular size. Shouldn't even start discussing lithium ion, but the danger of thermal runaway should alone be enough of a reason to plan it very carefully.

Don't get me wrong, renewables + storage is the future, aside from eventual fusion power it's the cheapest and most environmentally friendly alternative. But a lot of people talk as if there aren't enormous technical challenges in stabilizing a power grid with renewables at the moment. Remember that precisely all of the power that is put into the grid has to be pulled out of the grid, every minute of every hour of every day of the year, as soon as that equilibrium is broken in either direction we experience significant issues.

[–] [email protected] 2 points 1 year ago (1 children)

There's so much years old anti storage propaganda in your text, it's painful.

Hydrogen storage is not a mature technology yet

What makes a tech mature to you? We have all the components of a hydrogen storage path up and running everywhere around the world. They're not profitable, at least not without government incentives, but solarpunk is anti-capitalist, so profitability shouldn't be among our primary concerns.

something like 35% round-trip efficiency

That's a worst case figure for purely electrical round trip efficiency. We could use waste heat of the fuel cell process (to a lesser extent also the electrolysis process) in order to bump that number up considerably.

not to mention the issues with hydrogen gas leaking due to its small molecular size

That has not been an issue for quite some time thanks to advances in materials science. Also, we could use methanation, of course sacrificing some more efficiency, but then we could even use old natural gas infrastructure without an issue.

Shouldn't even start discussing lithium ion, but the danger of thermal runaway should alone be enough of a reason to plan it very carefully.

Lithium-ion batteries are environmentally bad for sure, but talking about thermal runaway? Really? You need very high temperatures for that to happen. Most stationary storage applications will never see such high powers that they come even close to thermal runaway by themselves. If in a high power application, you'll have better battery management systems supervising the temperature and reducing the allowed power. It's really a non-issue if you have engineers who know what they're doing working on it.

Coming bad to environmentally bad: see sodium-ion batteries.

[–] [email protected] 1 points 1 year ago

What makes a tech mature to you?

When significant issues have been worked out and it is, if not profitable, economically justifiable.

solarpunk is anti-capitalist, so profitability shouldn’t be among our primary concerns

I'm not primarily concerned with a Lemmy instance, I'm more focused on the world that we live in.

That’s a worst case figure for purely electrical round trip efficiency. We could use waste heat of the fuel cell process (to a lesser extent also the electrolysis process) in order to bump that number up considerably.

It's a reasonable estimate, not a worst-case figure, and waste heat works well when additional heat is required and incredibly poorly when it is not. Heat storage is also an alternative but now we're talking about requiring heat storage in order to make hydrogen viable, which bumps up the cost and reduces availability even further.

That has not been an issue for quite some time thanks to advances in materials science.

So this is not entirely true, leakage represents about 2.9-5.6% and hydrogen is an indirect greenhouse gas that can potentially have a 10 times bigger impact than CO2 over a 100-year period. Let's not fix problems by potentially causing more problems.

Lithium-ion batteries are environmentally bad for sure, but talking about thermal runaway? Really? You need very high temperatures for that to happen.

All that you need is bad luck with dendrite formation and the battery can combust during regular cycling. An energy storage facility in Australia caught fire a few years ago. The ship off the coast of the Netherlands that burned just weeks ago was potentially caused by brand new EV batteries combusting. It is a significant concern.

It’s really a non-issue if you have engineers who know what they’re doing working on it.

I am an engineer.

Coming bad to environmentally bad: see sodium-ion batteries.

What do you mean by "Coming bad to environmentally bad"? I think sodium-ion batteries represent an exciting step forward in battery development since it would reduce the need for a material which is often environmentally disastrous to extract. There are also other storage mediums that are developing, Liquid- and Compressed Air Energy Storage, Flow Batteries, and Liquid Metal batteries to mention a few. There's also the rust battery that's under development by Form Energy. I don't know why people get so hung up on hydrogen and lithium-ion batteries as if they're the only two possible alternatives when at least one of them sacrifices safety and longevity for weight in a use-case where weight isn't an issue.

I am interested in the tech, I'm trying to keep up to date with recent developments as it's both interesting and in the same field as my degree, and I do think that it's both inevitable that it will end up as the best alternative for the grid in the future and that there are exciting opportunities today. But we don't have to ignore risks and cram other technologies into there just because fossil fuels are bad, we can phase them out and make right decisions for the future at the same time.

[–] [email protected] -1 points 1 year ago (1 children)

Not everywhere, not all the time. Were that the case we'd be much farther ahead in getting rid of fossil fuels.

[–] [email protected] 2 points 1 year ago (1 children)

For everywhere else we can count on power lines

[–] [email protected] -1 points 1 year ago* (last edited 1 year ago) (2 children)

That shows quite some misunderstanding of how power transmission works...

Also, there's a very significant part of the world population living on islands. Even disregarding efficiency losses, do you want to crisscross the oceans with power lines?

[–] [email protected] 3 points 1 year ago

Why not? We have plenty of cables and so forth down their anyway and they are hardly that bad. Besides efficency losses for hvdc are at 3.5% for 1000km. So you could transport electricity from any place to any other place on earth with max loss of 49% using that technology. You also do not need millions of power lines and mostly not across oceans, but connecting islands with the next continent. Even then most islands with high enough population for nuclear to be even be reasonable are both large themself or close to some other continent or large islands. As for costs there is a serious private venture to built a direct undersea power line from Morroco to the UK. It is not cheap, but it certainly is not crazy. Obviously we have an electricity grid in most places in the world already, with 87% of the worlds population having electricity and nearly all who have no access are in Africa.

[–] schroedingershat 3 points 1 year ago* (last edited 1 year ago)

This is just typical reactionary absolutism.

"It has to cover every use case to be useful anywhere."

Rather than vague abstractions, make an actual case in a real place. Which island are you talking about? Guarantee there's a less costly renewable mix with higher uptime.

[–] iemgus 2 points 1 year ago (1 children)

Profit is the only real problem with nuclear. The US navy has 7000+ years of operating nuclear reactors without a major incident, and with minimal enviromental impact.

[–] [email protected] 2 points 1 year ago (1 children)

Ok, they are a bit different in scale and construction.

[–] iemgus 1 points 1 year ago

That's a good point. Having the large scale would afford more room for safety monitoring and control equipment, access for maintenance and operations, and better economies of scale on equipment cost.

Not to mention one plant stays in place on land with unlimited access to support equipment and personal while the other flys though the depths of the ocean, exposed to all its dangers and unpredictability with only the people and equipment that fit onboard.

[–] [email protected] 2 points 1 year ago

Our government is busy to make people pay for owning solar panels. So yeah profit is always more important and literally no government or company gives a shit about the environment.

I'm pretty sure people will start removing their solar panels here soon since no one wants to pay more for doing good.