Submitted 8 months ago by gandalf_der_12te@discuss.tchncs.de to technology@lemmy.world
https://ember-energy.org/app/uploads/2025/06/Ember-24-Hour-Solar-Electricity-June-2025-6.pdf
Some key insights from the article:
Basically, what they did was to look at how much batteries would be needed in a given area to provide constant power supply at least 97% of the time, and the calculate the costs of that solar+battery setup compared to coal and nuclear.
This is US centric, and panels are 1/3 cost in China, batteries 1/2, and labour/land 1/2 ish too.
just 17 kWh of battery storage is enough to turn 5 kW of solar panels into a steady 1 kW of 24-hour clean power
This is a bad model, though they are saying 3.4 hours of storage, and LasVegas as their best site. AC use is typically day only, but heat waves do make it a 24 hour demand issue on the longest solar production days. For LV, 5kw of solar will produce 32kwh/day, ranging in seasons from 29-35.5kwh. Already a problem for their 1kw “transmission setup” in that production is higher. The 2nd problem is that there is/can be higher demand during the day than night, due to AC.
The biggest problem of all is a battery in LV, even with 2kw transmission per 5kw solar, would charge in winter up to 19kwh of batteries. Summer 21.5kwh. The 2 big variables are batteries vs transmission size, and demand shifting opportunities, where necessarily fully charging batteries every day is a cost optimization, though fully delivering power on highest demand days is a revenue/price optimization.
cost assumptions are $563/kw solar-electrical hardware, and $181/kwh batteries. They may not include land and deployment costs. They use outdated pessimistic 20 year lifetimes. They have terrible comparisons to coal and NG as well.
Both coal and NG plants cost the same for basic peaker plant. A double efficient NG plant costs double, but loses flexibility. They have variable fuel costs and relatively fixed operation costs. Before covid, all 3 options cost $1/watt to build, giving a huge advantage to solar for not having fuel/operations costs.
A much easier way to model cost of solar+battery system is independently. Solar at $563/kw in LV to make 10% “yield” per year (covering full financing and a healthy profit). needs $56.30 revenue/year = 2.4c/kwh = $24/mwh. Even $1/w US system requires 4.27c/kwh The same base profit over operational costs as FF plants. Batteries last 30 years too, and 10% yield means a discharge/charge profit requirement of 5c/kwh at night, with possible double cycling from clouds/frequency balancing, or lunch cooking demand spike, where any profit is bonus profit.
So as long as duck curve/early evening/morning breakfast electricity markets are 7.4c/kwh TOU "wholesale"rates or higher, and daytime rates above 2.4c/kwh, solar + batteries (that fully charge every day) then that far beats any new dead ender energy plants. Also, for a 1gw transmission line, compared to OP model, you only need 1.7gw solar instead of 5gw.
In short term there are existing FF plants that can serve as backup, and where it is extremely undesirable to have any human activity in their surrounding areas, host solar to piggy back on their transmission capacity. That these plants were paid 20-40c/kwh to provide 10%-20% of power needs, with a combination of per kwh pricing, and fixed “stay ready for backup” payments, would permit these plants to stay open/operational. In short/medium term, EVs are a great resource to replace both utility batteries, and backup FF plants with more solar. Being paid 3-10c/kwh profit (depending on demand primarily from nightime AC/heating)
In long term, the path to solar+battery/EV power every day is much more solar with H2 electrolysis. $2/kg costs are already achievable today with 2c/kwh “surplus solar” input. It is an even more rapidly advancing tech/cost efficiency field. $2/kg is equivalent for a FCEV to $1/gallon gasoline vehicle range. It is 6c/kwh CHP (free domestic hot water energy), and 10c/kwh electric only energy, in addition to many chemical applications such as local fertilizer production. Electrolysis of NG is a more efficient (than water electrolysis) green H2 process that produces carbon black as byproduct. A solid precursor to graphene and battery electrodes.
H2 works today for places outside LV, where solar is much more variable. In Canada where long summer days may not need AC, high saturation solar can drop below 2c/kwh for 9 months, but be worth 15c/kwh for 80-90 days. A balance between existing energy systems and new solar works everywhere in the world. H2 export/import infrastructure also cost efficiently displaces much FF energy.
As long as daytime wholesale electricity rates in LV are above 2.4c/kwh, they need more solar. A similar number can be calculated elsewhere. Nuclear and more expensive combined NG energy cannot compete because daytime solar will cut into the hours they can sell energy.
every hour of every day
Works 97% of the time, every time!
As others have said this is for Las Vegas which receives wayyy more sun than the average place. But the other misleading part is they looked at 20 years which is close to the life cycle for solar/batteries and not even half the life of nuclear
they looked at 20 years which is close to the life cycle for solar/batteries and not even half the life of nuclear
Brother, with some luck a nuclear plant is in construction stage after those 20 years
China has been doing them in around 7 years from groundbreaking to grid connection and is trying to get that down to 5 years with their bailong power plant as they are developing an experienced work force and actually have experience making the parts
solar today is warranteed for 30 years. No reason to replace before 60 years compared to adding more beside it.
Batteries and panels degrade over time. So if you are trying to maintain a specific amount of power you would need to keep investing in order to maintain the same amount of power generation
But the other misleading part is they looked at 20 years which is close to the life cycle for solar/batteries and not even half the life of nuclear
I think Lazard’s LCOE methodology looks at the entire life cycle of the power plant, specific to that power plant. So they amortize solar startup/decommissioning costs across the 20 year life cycle of solar, but when calculating LCOE for nuclear, they spread the costs across the 80 year life cycle of a nuclear plant.
Nuclear is just really, really expensive. Even if plants required no operating costs, the up front costs are so high that it represents a significant portion of the overall operating costs for any given year.
The Vogtle debacle in Georgia cost $35 billion to add 2 MW of capacity. They’re now projecting that over the entire 75 year lifespan the cost of the electricity will come out to be about $0.17 to $0.18 per kilowatt hour.
Nuclear is just really, really expensive.
Subsidize it like you do oil, there, solved.
Vogtle’s numbers are incredibly biased considering they made an entire design and then had to redo it halfway through that’s not a realistic cost that can be expected for future projects. We also have vogtles design be approved now so that new plants can be built for a fraction of the cost. Also where did you see they did amortization of solar?
2gw, but yes, before any operational/maintenance costs that is $17.5/watt. Solar is under $1/watt, and sunny AF.
From the dot graph, it implies that las Vegas is one of the worse options? And Birmingham is somehow best?
Not sure I’m reading that right?
My understanding of that graph is how do you flatten peak energy demands, Birmingham is flat and throughout the year because you have some parts of the year where you need very little battery capacity and other parts where you need a lot. Las Vegas basically always needs a lot because of how hot it gets they end up with huge amounts of peak energy usage
Fair point but nuclear will probably always have the disadvantage of initial cost and time to market. It’s a huge risk for investors and public officials.
That is the main criticism of nuclear, it should hopefully get better with Westinghouse’s AP1000 receiving full approval and being built all across China so as long as we continue to use the same design it can start to be mass produced instead of making all the parts as one offs that are much more expensive and time consuming
Not where I live. By far. Not to mention that it doesn’t even cover winter months at all. Battery or no battery it doesn’t cover even the usage most of the time when the sun is out, let alone charge the battery.
See and this is why we need to subsidize poor old coal. It can't compete without it. Won't someone think of the miners! /s
I think the current politicians do too much thinking about minors
Coal has long been unprofitable, and nuclear has always needed huge state funding (you get weapons as the byproduct of nuclear power, hence the subsidies). Until it beats gas it still isn’t cheap enough imo. Gas of course is still massively subsidised too though, and that’s where we need to continue to work: our policy makers need to end fossil fuel subsidies
you get weapons as the byproduct of nuclear power
Not necessarily depends on the reactor type.
Look at the other line on the graph. Solar alone, covering up to 60% of energy use, is already cheaper than gas in Las Vegas. Sure, other places will have their own lower numbers, but until we achieve this threshold, we’re just a bunch of reactionaries captured by current business owners. If anyone actually believed in the free market, we’d expect it to trend to that line
I work in this field. I’m trying to change these numbers! We are heading the right direction is the good news. China may well save us all with cheaper panels and battery manufacturing. And if 97% reduces our emissions even 50% on todays emissions then we can start talking about actually meeting some climate targets.
So this is all good news, but as I also said: I work in this field and know we have a long way to go yet. There also isn’t a single answer. Batteries, smart grids, grid-interconnects, efficiencies, supply mixes, demand offsetting; power is the best thing in the world to work in right now, it touches sooo many aspects of humanity and is changing so fast!
97% sounds impressive, but thats equivalent to almost an hour of blackout every day. Developed societies demand +99.99% availability from their grids.
The diagram shows that they fall short on winter mornings
My own modelling to decide what size battery I want for my house says it’s easy almost every day, but when you have three rainy and overcast days in a row you need a battery far larger or an alternative. For me the alternative is the grid; at grid scale it’s gas generators
If somebody has to keep that gas generator serviced only to run it on winter mornings, that electricity is going to be very pricey.
i’m sure you can squeeze out a measly 3% from wind and hydro, no?
using old/existing FFs 3% of the time instead of 100% is a 97% emission reduction.
It sound impressive, until you read it’s Las Vegas. In places like Germany you have several weeks per year with neither enough sun nor wind. With backup power like gas turbines which run few weeks per year you have to subsidize the operators. And if you want run them on green hydrogen, massively overbuild the renewable capacity so that you can fill up gas storage during summertime.
The point is if 97% of the energy is cheaper… Then you would have to pay more than coal for 3%. Which you could use any other form to supplement that, or just pay more for that 3% as the prices keep dropping and it will be below it soon. Countries use more than one source of energy. Whether you use a nuclear plant, hydro, geothermal, wind, or even gas/coal to supplement that 3% until it becomes cheaper (likely in the next 3 years)… and then we’ll just burn off the extra energy in useful tasks hopefully. You could do anything with it. Shit hook it up the pumps and lift water up into towers and tell people if we have to much energy we need to burn off you’ll get extra water pressure for your showers or something. Use it for desalinization of saltwater to send to areas in a drought. Can power the shipping to get it there as well. Idk, there’s always something useful we need energy for.
Then get it from the sources that already exist. 97% coverage is a great milestone.
Funny enough lots of people hate that. Lots of people have binary thinking, it’s either 100% coal or 100% solar.
97% is great (though that is just for vegas) but it is still a long way from enough. Its a truism of availability that each 9 of uptime is more difficult to get to than the last, i.e. 99.9% is significantly more difficult/expensive than 99%
Then get it from the sources that already exist.
The problem here is that you cant simultaneously say “Solar is so much better than everything else we should just build it” and “we’ll just use other sources to cover the gaps”. Either you calculate the costs needed to get solar up to very high availability or you advocate for mixed generation.
None of which is to say that solar shouldnt be deployed at scale, it should. We should be aware of its limitations howver and not fall prey to hype.
This is still more polluting to mine than going nuclear, even accounting for nuclear waste.
absurd. Uranium mines need huge exclusion zones. In fact the biggest ones have large enough exclusion zones that more solar energy could be harvested than the energy content of the uranium underneath.
Not all reactors use uranium.
What’s the exclusion zone of rare earth mines ? Of the terrible chemicals required to extract those products ? Same question with the batteries. What’s the impact of the shade on agriculture ? How about all the steel, concrete and composites on the environment, how do they degrade ? Is it in micro plastics ?
I didn’t say nuclear energy was good, just that solar panels are worse. The perfect energy source doesn’t exist but currently all the data I’ve come across points to the direction that nuclear is significantly better than all other renewables and don’t require significant battery storage.
Also if anti-science ecologists hadn’t blocked so many fast neutron reactors, we’d be further along to a tech that can burn existing thorium stockpiles for 8000 years without further mining and while producing significantly less dangerous waste than current reactors. I guess we’ll just buy the design from China and Russia who didn’t stop the research and have currently operating reactors right now.
Why compare it to nuclear rather than what’s currently being used in that area? Coal and gas.
Nuclear is good for providing a stable base load, but having the entire grid be nuclear would be very expensive. And if everyone were to do the same, the market cost of fissile fuel materials would skyrocket.
Lots of solar and wind in the energy mix is a no-brainer.
shhh!
how can we develop a whole new market to make the rich richer if you keep bringing those kinds of facts in here?
What’s the power source that doesn’t do that? How do I advocate for it?
Do you have a source for that claim? Genuine question.
My intuition is that the types of impact are widely different, so hard to reduce to a single number that can be compared.
docs.nrel.gov/docs/fy21osti/80580.pdf
I’m using table 1.
PV panels alone produce 43g/kWh, batteries 33.
Nuclear (light-water or pressurized) are at 12.
We’re talking complete life cycle analyses.
He is probably referring to the small amount of nuclear waste that is actually produced per watt of power, it is a lot more dangerous if you are in direct contact, but it is surprisingly easy to store safely, and remove all environmental impact. The biggest environmental issue with nuclear is the mining and enriching, both of which are realistically too small to factor in.
I found this article going into more depth nuclear waste .
I you live where sun is abundant all year round… In which case (Las Vegas?) I would question the choice of having humans living in a fucking desert in the first place. But man I wish I could cover my needs between October and March here in Europe but no battery will help me store so much for so long :-/
theres also nothing much going on LV too, limited schools and and private physicians.
“bad” solar areas are actually amazing for 9 months, and if you heating needs are met by other means, then winter can keep the lights on and still do cooking. The path to meeting winter heating needs is hot water and “heated dirt/sand” storage with hydronic floor heating (where more water is delivered at 30C is easier to manage than radiators at 80C) that can be stored during ample fall solar with no heat or cooling load.
Exactly that. My worst case winter month (not even by day and I like to be warm every day) is generating less than 25% of consumption. Not that other winter months are much better.
I feel you… I got a nice 3k€ to pay for electricity just for winter months and that’s with a quite performant heat pump. But at least zero emissions here…
Does the wind blow year round? I’m imagining a similar case for wind, then you can say that for the union of these two sets, renewables are cheaper than legacy energy
I would have loved that but having a wind turbine is… not easy. Permits, psychotic attitude from neighbours… but that have been my go-to given we don’t have a stream to go hydro. I’m still happy with covering 8 ou of 12 months with our setup but it’s still unnerving to swallow the costs of the setup + utilities for winter months…
Yeah I saw that… Though I’m 3 years into solar and my measurements aren’t so positive. I am definitely not covering 62% of our needs yearly. The 4 less sunny months are killers when you need heating.
nshibj@lemmy.world 8 months ago
Where?
iknowitwheniseeit@lemmynsfw.com 8 months ago
Very sunny places, like Los Vegas.