this post was submitted on 16 Nov 2024
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Sometimes the sun doesn't shine, sometimes the wind doesn't blow. Renewables are great and cheap, but they aren't a complete solution without grid level storage that doesn't really exist yet.
Solar with Battery grid storage is now cheaper than nuclear.
If the demand goes up I have some doubt, also, mining for Lithium is far from being clean, and then batteries are becoming wastes, so I doubt you would replace nuclear power with this solution
I guess in some regions it could work, but you're still depending on the weather
You don't need lithium. That's just the story told to have an argument why renewables are allegedly bad for the environment.
Lithium is fine for handhelds or cars (everywhere where you need the maximum energy density). Grid level storage however doesn't care if the building houising the batteries weighs 15% more. On the contrary there are a lot of other battery materials better suited because lithium batteries also come with a lot of drawback (heat and quicker degradation being the main ones here).
PS: And the materials can also be recycled. Funnily there's always the pro-nuclear argument coming up then you can recycle waste to create new fuel rod (although it's never actually done), yet with battery tech the exact same argument is then ignored.
Density doesn't matter much when it comes to grid scale, indeed.
What battery technologies are you thinking of? Zinc-ion? Flow batteries?
They're currently bringing sodium batteries to market (as in "the first vendor is selling them right now"). They're bulky but fairly robust IIRC and they don't need lithium.
If you're thinking of the portable battery marketed as 'solid state' then that was a scam - a teardown revealed it was just lithium cells
Nah, I'm thinking of sodium-ion batteries. That's 1990s tech and is currently in use for grid storage. Several manufacturers are currently bringing car-ready Na-ion batteries to market and there seems to be one production car using them in China (a version of the JMEV EV3, which I hav enever heard about before).
Now, Na-ion is still less mature than Li-ion and that Chinese car gets about 17% less range compared do the Li-ion version.
you know that grid storage does not always mean "a huge battery", you can also just pump water in a higher basin oder push carts up a hill and release the potential energy when you need it...
Pumped storage is a thing yeah. But might just as well go full hydro, if you're doing the engineering anyways.
I feel like we're missing the part about "push carts up a hill", which involves virtually no serious engineering difficulties aside from "which hill" and "let's make sure the tracks run smoothly". See: the ARES project in Nevada
Yeah, that's 50MW, storing power for 15 minutes, so 20MWh. (1).
There's also a similar company: gravicity.
They're a fun academic endeavour. But if gravity provides the potential, water beats them per dollar spend. It's not even close.
So do regular batteries.
A fair point, but given how the best places to build solar infrastructure tend to not have easily accessible large volumes of water, I should think that economies of scale can apply if we were to put actual investment into scaling up the gravitational potential. Sure, it's not a geometric law like for kinetic energy, but greater height and greater mass are both trivial quantities to scale in places with large empty areas. I'm simply pointing out that we've never invested in that obvious possibility as a civilization. Am I missing something obvious that makes the scaling non-viable?
Transportation of electrical power is quite efficient. I think that colocation of generation amd storage are economically rarely a technical necessity.
I can see it work in terms of national security, but then again, regular li-ion have better economics.
The biggest problem with gravitational potential is P=mgh, that is, potential energy only grows linearly in mass and height.
I agree with you on the linearity issue. I just feel like using its size as a criticism is invalid, given that the very source you cited pointed out that the reason it's so small is because they chose to reuse an already-disturbed site, rather than building it on 100 acres of BLM land, which I'd argue is quite admirable. The colocation point is also fair, though our water resources in the entire american west are severely limited, and will become moreso over the next 50 years. Utah's declining snowpack and the overdrawn Colorado can only cover so much. I feel like, while the GPE law is linear for both mass and height, the fact that we can scale both is a point in favor of both pumped hydro and rail storage, and rail storage can be stored virtually indefinitely, as long as it doesn't have time to rust in place. Being able to supplement the off-hours is absolutely doable with rail.
In practice, you're usually using existing geography (historical or geographical) for height. So you're left with scaling m.
I honestly also hoped it would be a great idea. I donated to gravicity back in the day. You live and learn.
Again, a fair point. Assuming that anyone with an idea of the meaning of "potential energy" survives the next ten years, I'd still like to see it more fully explored in the american west, but it is, unfortunately, rather a moot point for at least five years.
Ah that's politics.
I'm fine with talking polite politics. So far you seem to me like a polite and educated person.
My point of view is from EU, not US. To me US always looked like higher highs, and lower lows, in terms to a person's achievements.
To me, EU always seemed like: wear the uniform, don't stand out. No new ideas please.
I envy living in US.
That's interesting. For me, I guess it's a "grass is greener" scenario. I look at the headway various countries in the eurozone have made on topics from socialized medicine, to universal basic income, to free postsecondary education, to the protection of personal data, and even to forcing Apple to change its charging cable to the standard USB-C. That change of policy forced them to change it here, as well. The EU's stodginess helps people even beyond its borders. My students ALL have iPhones, and It's unbelievable to witness the ease with which they can access their devices now, vs. when they were all forced to use a specialized cable for connection and charge. America hasn't even figured out high-speed rail yet. As an american who teaches secondary science to a bunch of naturalized citizens under the age of 18, I don't think I can stay through the next 4 years. I fear the pogroms, if not for myself, then for my students and their families. I can't have my tax dollars go towards a repeat of the mistakes of 90 years ago. I'm thinking New Zealand is looking comparatively nice (though apparently there's a growing nationalist movement there as well).
In general, I do sense that there is a significantly greater sense of "rugged individualism" in the US, compared to many other countries, but I see the costs of that individualism more acutely because of its proximity. People seem to be largely incapable of consideration here, from anti-vaxx and anti-mask movements to the hesitance to tax the wealthiest individuals due to the thought that "maybe that'll be me one day". It's really quite distressing.
I think the socialized medicine and socialized postsecondary education are the biggest advantages indeed.
This comes at the cost of way lower wages, and smaller wage diffrrences. An educated engineer's take home pay is maybe 1.2 times that of a factory worker. Resulting in very little people actually persuing STEM.
Combine that with the deindustrialization that's going on in the EU, as it can't compete with Asia, we will have to see how long it lasts. Lots of uneducated (even as education costs are socialized, most don't persue it) are already without a job, and the number keeps growing.
It's a trade-off, on which I can understand your point of view, as to how it benefits individuals in the short and mid-long term.
Universal basic income does, to my knowledge, not exist in the EU.
Those were/are popular here, too.
There's likely a "grass is greener" going on, for the both of us, indeed :)
I mainly look at the lack of innovation happening in EU. Missed the whole of tech, machine learning, no innovative industry, no fintech, little to no biotech as GMOs are outlawed. Only farma is doing well. It's a terrible restrictive place if you've an inquisitive mind.
Yeah, lithium mining and processing is extremely toxic and destructive to the environment. On one hand, it's primarily limited to a smaller area, but on the other hand, is it sustainable long-term unless a highly efficient lithium recycling technology emerges? And yes, I know there are some startups that are trying to solve the recycling problem, some that are promising.
Would love to see a source for that claim. How many 9's uptime do they target? 90%, 99%
This is old news now! Here's a link from 5 years ago. https://www.forbes.com/sites/jeffmcmahon/2019/07/01/new-solar--battery-price-crushes-fossil-fuels-buries-nuclear/
This is from last year: https://www.lazard.com/research-insights/2023-levelized-cost-of-energyplus/
As to uptime, they have the same legal requirements as all utilities.
I was pro nuke until finding out solar plus grid battery was cheaper.
Source (1)
The project is 1 GW of solar, 500MW of storage. They don't specify storage capacity (MWh). The source provides two contradicting statements towards their ability to provide stable supply: (a)
And (b)
Source (2) researches "Levelized cost of energy", a term they define as
It looks at the cost of power generation. Nowhere does it state the cost of reaching 90% uptime with renewables + battery. Or 99% uptime with renewables + battery. The document doesn't mention uptime, at all. Only generation, independant of demand.
To the best of my understanding, these sources don't support the claim that renewables + battery storage are costeffective technologies for a balanced electric grid.
Yes.
But then you added the requirement of 90% uptime which is isn't how a grid works. For example a coal generator only has 85% uptime yet your power isn't out 4 hours a day every day.
Nuclear reactors are out of service every 18-24 months for refueling. Yet you don't lose power for days because the plant has typically two reactors and the grid is designed for those outages.
So the only issue is cost per megawatt. You need 2 reactors for nuclear to be reliable. That's part of the cost. You need extra bess to be reliable. That's part of the cost.
I'm referring to the uptime of the grid. Not an individual power source.
Assume we've successfully banned fossil fuels and nuclear, as is the goal of the green parties.
How much renewable production, and bess, does one need to achieve 90% grid uptime? Or 99% grid uptime?
If you want a balanced grid, you don't need to just build for the average day (in production and consumption), you need to build for the worst case in both production and consumption.
The worst case production in case for renewables, is close to zero for days (example). Meaning you need to size storage appropriatelly, in order to fairly compare to nuclear. And build sufficient production so that surplus is generated and able to be stored.
If we're fine with a blackout 10% of the time, I can see solar + bess beating nuclear, price wise. If the goal instead is a reliable grid, then not.
As an example: take Belgium. As a result of this same idea (solar/wind is cheap!) we ended up with both (1) higher greenhouse gas emissions and (2) costlier energy generation, as we now heavily rely on gas power generation (previously mainly russian, now mainly US LNG) to balance the grid. Previous winter we even had to use kerosene turbine generation to avoid a blackout.
About 115% to 130%. Depending on diversification of renewable sources and locations. The remains are losses in storage and transport obviously.
But shouldn't you actual question be: How much storage is needed?
For a quick summary of those questions you can look here for example...
What would 130% grid uptime even look like? 475 days a year without blackout?
I think we're talking about different things.
130% production on average, with excess being stored, minus losses in conversions, transport and storage = 100% demand covered all the time.
Or the longer version: For a stable grid I need to cover 100% of the demand in next to real-time. This can be achieved with enough long- and short-term storage, plus some overproduction to account for storage losses. The 115% to 130% production (compared to actual demand) are based on studies for Germany and vary by scenario, with the higher number for the worst case (people strongly resisting all changes to better balance consumption and south Germany keeping up there resistence to diversify by only building solar while blocking wind power).
The question now is: How much storage do I need? And that answer is varying by much greater amount based on scenario (for example between 50 and 120 GW capacity needed as electrolysis for long term-storage or battery storage between 50GWh and 200GWh).
Yes you have to build for worst case. That's what I already said.
You are comparing overbuilt nuclear but acting like bess can't be over built too. That's why the cost of storage is the only important metric.
You need an absolute minimum of 2 nuclear reactors to be reliable (Belgium has 7). That doubles the cost of nuclear. But it doesn't matter because that's factored in when you look at levelized cost. You look at cost per MWhr. How reliability is achieved doesn't matter.
Bess is $200 per MWhr.
Uptime is calculated by kWh, I.E How many kilowatts of power you can produce for how many hours.
So it's flexible. If you have 4kw of battery, you can produce 1kw for 4hrs, or 2kw for 2hrs, 4kw for 1hr, etc.
Nuclear is steady state. If the reactor can generate 1gw, it can only generate 1gw, but for 24hrs.
So to match a 1gw nuclear plant, you need around 12gw of of storage, and ~~13gw~~ 2gw of production.
This has come up before. See this comment where I break down the most recent utility scale nuclear and solar deployments in the US. The comentor above is right, and that doesn't take into account huge strides in solar and battery tech we are currently making.
That's stored energy. For example: a 5 MWh battery can provide 5 hours of power at 1MW. It can provide 2 hours of power, at 2.5MW. It can provide 1 hour of power, at 5MW.
The max amount of power a battery can deliver (MW), and the max amount of storage (MWh) are independant characteristics. The first is usually limited by cooling and transfo physics. The latter usually by the amount of lithium/zinc/redox of choice.
What uptime refers to is: how many hours a year, does supply match or outperform demand, compared to the number of hours a year.
This is incorrect. Under the assumption that nuclear plants are steady state, (which they aren't).
To match a 1GW nuclear plant, for one day, you need a fully charged 1GW battery, with a capacity of 24GWh.
Are you sure you understand the difference between W and Wh?
My math assumes the sun shines for 12 hours/day, so you don't need 24 hours storage since you produce power for 12 of it.
My math is drastically off though. I ignored the 12 hrs time line when talking about generation.
Assuming that 12 hours of sun, you just need 2Gw solar production and 12Gw of battery to supply 1Gw during the day of solar, and 1Gw during the night of solar, to match a 1Gw nuclear plants output and "storage."
Seeing as those recent projects put that nuclear output at 17 bil dollars and a 14 year build timeline, and they put the solar equivalent at roughly 14 billion(2 billion for solar and 12 billion for storage) with a 2 - 6 year build timeline, nuclear cannot complete with current solar/battery tech, much less advancing solar/battery tech.
Again, I think you might not understand the difference between W and Wh. The SI unit for Wh is joules.
When describing a battery, you need to specify both W and Wh. It makes no sense, to build a 12GW battery, if you only ever need 1GW of output.
If you want more exact details about the batteries that array used, click on the link in my comment.
The array has a 380 MW battery and 1.4Gwh of output with 690Mw of solar production for 1.9 billion dollars. Splitting that evenly to 1 billion for the solar and 1 billion for the battery, we get 2.1Gw solar for 3 billion, and 12.6Gwh for 9 billion.
So actually, the solar array can match the nuclear output for 12 billion, assuming 12 hours of sun.
For 17 billion, we can get a 3.3Gw generation, and 15.6Gwh of battery. That means the battery array would charge in 7-8hrs of sun, and provide nearly 16hrs of output at 1Gwh, putting us at a viable array for just 8hrs of sun.
Can solar + battery tech do what nuclear does today, but much faster, likely cheaper and with mostly no downsides? That is a clear yes. Is battery and solar tech advancing at an exponential rate while nuclear tech is not? Also a clear yes.
Nuclear was the right answer 30 years ago. Solar + battery is the right answer now.
How many days a year does that occur? How much additional storage and production do you need add, to be able to bridge dunkelflautes, as is currently happening in germany, for example (1)?
That's why I mentioned the 90%, 99%, etc. If you want a balanced grid, you don't need to just build for the average day (in production and consumption), you need to build for the worst case in both production and consumption.
The worst case production in case for renewables, is close to zero for days on end. Meaning you need to size storage appropriatelly, in order to fairly compare to nuclear.
So you agree that solar + battery resolves 90-99% of power needs now at a drastically reduced cost and build time than nuclear today?
I expect that 10% will get much closer to 1% in the next decade with all the versatile battery/solar tech coming onboard, but to compensate for solar fluctuations, you use wind, you use hydro, and you use the new "dig anywhere" steady state geothermal that is also being brought online today. We can run more HVDC lines to connect various parts of the country also. We are working on some now, but not enough. With a robust transmission system, solar gets 3hrs of "free" storage across our time zones. With better national connections, power flows from excess to where its needed, instead of being forced to be regional.
Worst case? You burn green hydrogen you made with your excess solar capacity in retrofitted natgas plants.
There are lots of answers to steady-state that are green and won't take 15-20 years to come online like the next nuclear plant. We should keep going with them, because they can help us now and in the future.
I'm saying you can get to 90% yes.
But, as often happens, the last 10% is as hard or harder as the first 90%. The law of diminishing returns.
I'm aware of and have studied them. But general public seems to greatly underestimate the scale of storage that's needed. Germany, for example, consumes about 1.4TWh of electrical energy a day. That's more than the world's current yearly battery production. It does not suffice to power Germany, for one day.
Pumped storage, if geology allows for it, seems like the only possible technology for sufficient storage.
Demand side reduction is possible as well, but that's simply a controlled gray out. The implications for a society are huge. Ask any cuban or south african.
Others, like lithium ion batteries, green hydrogen, salt batteries, ammonium generation, ... have been promised for decades now. Whilst the principle is there, they do store power, it simply does not scale to grid scaled needs.
The sad part is that it sets a trap, like we in EU have fallen into. You get far along the way, pat yourself on the back with "this windmill powers a 1000 households" style faulty thinking. But as you can't bridge the last gap, your reliance on fossil fuels, and total emissions, increases.
There is no law of diminishing returns. That's an aphorism, not an actual scientific principle. If your power source can generate the power, it does so.
You don't need to store an entire county's power per day. Thats never been anyone's goal, nor is it needed. You generate power for at least half of it, then continue to generate power with other green sources while also storing it.
You need to "restudy" the current state of battery tech and geothermal. There are huge arrays of different batteries being built now. These are 100hr storage batteries that cost 1/10 the price of lithium. They aren't on the drawing board, but rather being produced now in a mega factory.
There are also active MW scale "geothermal anywhere "plants in operation, with more coming. That same company has a 400MW geothermal plant that will be built in 4 years underway now. That alone is more competitive than nuclear.
The tech is here now, being built as we speak. Nuclear cant keep up.
Thats a chicken/egg peoblem. If enough renewables are build the storage follows. In a perfect world goverments would incentivice storage but in an imperfect one problems have to occure before somebody does something to solve them. Anyway, according to lazard renewables + storage are still cheaper than NPPs.
Imagine this (not so) hypothetical scenario:
Yellowstone or another supervolcano erupts and leads to a few years of volcanic winter, where there is much less sunshine. This has historical precedent, it has happened before, and while in and of itself it will impact a lot of people regardless of anything else, wouldn't you agree it would be better to have at least some nuclear power capacity instead of relying solely on renewables?
Sure, such a scenario is not probable, but it pays to stay safe in the case of one such event. I would say having most of our power from renewables would be best, having it supported by 10-20% or so nuclear with the possibility of increase in times of need would make our electric grids super resilient to stuff
Yeah let me imagine a supervolcano explosion of that scale to effect global weather patterns. What do you think will happen to your reactors? No, they are not indestructable just because they can handle an earthquake of normally expected proportion.
Nature catastrophes are the top 1 danger to nuclear energy. See Fukushima.
And the real question here would be a comparison between risk of a nuclear accident event and a renewables-impacting climate event.
https://www.theguardian.com/environment/2024/oct/24/power-grid-battery-capacity-growth
Let's be clear, the only reason grid-level storage for renewables "doesn't exist" is because of a lack of education about (and especially commitment to) simple, reliable, non-battery energy storage such as gravitational potential, like the ARES project. We've been using gravitational potential storage to power our mechanisms since Huygens invented the freaking pendulum clock. There is simply no excuse other than corruption for the fact that we don't just run a couple trains up a hill when we need to store massive amounts of solar energy.
How about basic maths? I
Scale is a huge fucking issue. The little country of the Netherlands, where I happen to live, uses 2600 petajoule per day. So let's store 1 day of power, at 100% efficiency, using the tallest Alp (the Mont Blanc).
Let's round up to 5000 meters of elevation. We need to store 2.6e18 joules, and 1 joule is 100 grams going up 1 meter. So to power a tiny little country, we need to lift roughly 5e13 kilos up the Mont Blanc. To visualize, that's 1.7 billion 40ft shipping containers, or roughly 100 per inhabitant.
Using 555m blocks of granite, you'd need 166 million of them (9 for every person in the country). Assuming a 2% slope, you'd need to build a 250.000m long railway line. And if you lined all those blocks up, with no space in between, you'd need 3328 of those lines (which then couldn't move, because they fill the entire space between the summit and sea level).
And that's just 1 small country.
And hey, you know what, that's almost got a point. Firstly, I'm in the US, and I'll freely admit that my comment was highly US-normative. However, I believe my comment on government corruption stands for the US case, where there is an insane amount of space that is already partly-developed in random bits of desert.
Now, let's get into your claims against the Netherlands case. Let's do some "basic maths":
Quod Erat Demonstrandum.
[1] https://www.iea.org/countries/the-netherlands [2] https://en.wikipedia.org/wiki/List_of_countries_by_electricity_consumption [3] https://aresnorthamerica.com/nevada-project/ [4] https://aresnorthamerica.com/gravityline/ [5] https://energy.nv.gov/uploadedFiles/energynvgov/content/Programs/4%20-%20ARES.pdf
ETA: rectify a quote ("just 1 small country"), and make it more civil in response to the prior commenter removing some of their more condescending language.
You're right in that I used yearly numbers and wrongly used them as daily numbers. The stats are from the central statistics bureau, and unfortunately it auto translates poorly https://www.cbs.nl/nl-nl/cijfers/detail/83989NED
The numbers include use of gas and coal for heating and industry, which often get ignored by people (mostly because it makes us look fucking terrible in renewable power stats).
It is, in fact extremely generous, if you're using the solar+storage method. But let's go with this and I'll demonstrate what it means in practice.
You just made the switch from "energy used" to "electricity generated". For a country that still does most of its heating with imported gas, that's a big difference. The real amount of non-fossil energy is about 18%, call it 80% fossil.
So it's 50% of 80% of 2600/365, or 2.8 petajoules. So that's only 10 of those facilities. Not great, not terrible. But that's not the point. Nor is it important that their demo facility has a height difference twice that of the whole country.
Let's stick with the "one night of power store is plenty".
That's true, but only if you can use solar to power your whole day. In other words, to make do with only 1 night of storage, you need to generate all your power for 24 hours in December during December daylight hours. Assuming it doesn't snow, one solar panel produces about .15kwh on a december day (working off of 2% of yearly production happening in december, and 300Wattpeak panels), or 540kj.
So you're right, we only need to build 10 facilities twice the height difference of the entire country, to save one night of energy use. Unfortunately in order for that to be true, we would also need to cover about 960.000 hectares in solar panels, which is roughly twice the total built up area in the country, including roads.
And that's assuming you keep a perfectly level energy use throughout the year, and a perfectly level production during December. Neither of which is true, and generally the worst days for solar production are the worst ones for use as well.
On the bright side, if we can put down two extra cities worth of solar panels for every city, we'll probably have no issues building 600m tall hills by hand as well.
Alright, now we agree: solar isn't for everywhere, and the gravity storage method won't work in most places. You need preexisting slope, and my original comment was highly US-normative. As such, yes, we would need huge swathes of solar and wind collection sites, passive wave generators, pumped hydro and, yes, perhaps nuclear. Not everything will be "on" all the time. As far as the energy vs. Electricity numbers, while I vacillated between different terms, I WAS quite careful to only include electricity numbers throughout my stats and, again, none of my points were trying to prove that solar, specifically, is the right answer for the netherlands in exclusion of all else, but only that a significant energy storage problem can be solved with gravitational potential, and that the solution IS scalable if sites are selected carefully, and the fact that this has not been tried at scale anywhere in the world is due to government corruption. Still a US-normative idea, which I'll grant, but still true, when you have places from morocco to the Gobi, to the outback to the western US, all with significant natural elevation change, significant open areas, and excellent prospects for renewable energy sources of ALL kinds.
Also, as far as solar panels go, remember that actual diode solar panels are NOT the only way to harvest solar energy (let alone the cheapest). Mirrors can easily be used to boil water, and this plan was nearly attempted throughout egypt a hundred years ago (see Frank Shuman's solar thermal generators). However, I'm not about to argue that we should put giant solar collectors in one of the countries that is simultaneously the most population-dense (3rd highest in europe, IIRC) AND in a climate where large-scale solar is somewhat inefficient, ESPECIALLY when you have so much available wind power.