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Solar Energy Saves Europeans $135M a Day

cleantechnica.com

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Re: Solar Energy Saves Europeans $135M a Day

#141

Post by triceratops »

cubefox wrote: post #136
triceratops wrote: post #130

Earlier quoted context omitted.

Logic. If energy is already cheap, building out any new power source is unnecessary. Once you've determined you need new electricity generation, the cheapest source tends to get built. Right now that's solar; that's an objective fact.

That's not how it went through. The Green party in Germany heavily pushed against nuclear energy and coal energy and for solar energy. Now nuclear has been phased out and solar is here. Energy prices have gone up. Possibly because solar is extremely expensive during the night or on overcast days, so expensive gas power plants have to be used during that time. The old nuclear and coal plants would have been cheaper th…

> Now nuclear has been phased out

You can't really blame solar for phasing out nuclear. That was a political decision. Uranium mostly comes from Russia and China too, so it's not like it was geopolitically "safer" than gas.

> The old nuclear and coal plants would have been cheaper than replacing them with solar and gas.

Gas's share of electricity generation has not meaningfully changed in Germany since 2015. [1] It's ranged from 80 to 95 TWh. Last year it was 82 TWh.

That data also shows coal's share of generation reducing since 2022. If coal is really cheaper than solar and wind, why is Germany using less of it?

> Possibly because solar is extremely expensive during the night or on overcast days

Today gas power plants cover the shortage. As I've already showed you, Germany isn't using meaningfully more gas than it used to even during nuclear's heyday (which was in 2006, when nuclear generated 167 TWh and 74.6TWh came from gas).

Solar and batteries are already cheaper than gas in sunny climes. [2] It's only a matter of time before they're the cheapest source of nighttime power in Germany.

You're operating on information from 3 years ago and haven't changed your mind since then.

1. https://ember-energy.org/data/electricity-data-explorer/?ent...

2. https://ember-energy.org/app/uploads/2025/06/Ember-24-Hour-S...

Re: Solar Energy Saves Europeans $135M a Day

#142

Post by plqbfbv »

ramesh31 wrote: post #78
polairscience wrote: post #72

Earlier quoted context omitted.

This perspective is always so myopic to me. I say this as someone who doesn't make much money who's in the middle of a massive solar install (DIY). I made some simulations and a spreadsheet to work out all of the scenarios and I figured out that with a loan I can come out at monthly financing costs nearly exactly my electrical bill every month. That's right, I can have a 12 kWh battery backed 18 kW whole-home install…

>"Saying there's no "ROI" is looking at the situation like the only variable is your monthly expenses." That's the reality of life for most people outside of our little bubble of six figure earners. If it's a higher monthly price, it's a nonstarter. >"Additional home value/equity" I wouldn't be so sure of that. Solar is a massive maintenance liability that a majority of buyers will avoid. Fine if you find the right o…

> Solar is a massive maintenance liability that a majority of buyers will avoid

My parents put up solar in 2005 when it was very expensive. The original panels, inverters, cables are all still there, nothing had to be replaced in the last 21 years. The only maintenance task is a recommended (not mandatory) yearly cleaning that is probably in the 300€ range and takes maybe 1h, but since 5 years they have 2x EVs and 2x Powerwalls and are self-sufficient for 80% of the year, so that cost is negligible. The area where they live also has enough rain that if they skip cleaning for 1 or 2 years, the average total output is still close to the max they can get.

Re: Solar Energy Saves Europeans $135M a Day

#143

Post by triceratops »

have_faith wrote: post #60
ifjfkfkfkfj wrote: post #42

Earlier quoted context omitted.

Yeah more dependency on china! Nothing to backfire, no Chinese influence at all!

China might produce the most panels at volume but this isn't a hardline monopoly like being able to cut off oil pipelines. We can produce panels ourselves if we _need_ to (as a coalition of friendly countries), it will of course be more expensive, but expensive is better than not possible. Also, the more panels we already have, the less reliant we are. Energy doesn't stop flowing because deliveries of new panels stop…

> this isn't a hardline monopoly like being able to cut off oil pipelines

"Solar panels come from China" is a made-up problem. Oil pipelines and oil production equipment already have supply chains rooted in China and no one worries about that.

Re: Solar Energy Saves Europeans $135M a Day

#144

Post by sfn42 »

ndhbxyd wrote: post #98
sfn42 wrote: post #35

Earlier quoted context omitted.

Across a large enough area it's always sunny somewhere. And clouds don't interfere as much as you'd think. Add in wind, hydro, nuclear and some gas and you can handle pretty much anything just fine.

That has nothing to do with where factories, mines, farms etc are already located. You have to buy land to connect the power plant to the load and some guy in the middle wont sell. Handle congestion/maintenance of those lines etc. Lots of issues beyond just generation that the grid already is dealung with even though massive solar plants have been built. But main thing is weather forecasting has to get better because…

There's this thing called the power grid, it transports electricity across great distances.

And everything you're talking about is an issue with any kind of production, I don't know why you're bringing it up as if it's unique to solar. If you're building a factory that needs high amounts of stable power then you plan accordingly. Doesn't change the fact that solar is a useful way to generate electricity. I don't think anyone is saying we have to use it exclusively. We can use different solutions for different problems.

Re: Solar Energy Saves Europeans $135M a Day

#145

Post by ndhbxyd »

sfn42 wrote: post #144
ndhbxyd wrote: post #98

Earlier quoted context omitted.

That has nothing to do with where factories, mines, farms etc are already located. You have to buy land to connect the power plant to the load and some guy in the middle wont sell. Handle congestion/maintenance of those lines etc. Lots of issues beyond just generation that the grid already is dealung with even though massive solar plants have been built. But main thing is weather forecasting has to get better because…

There's this thing called the power grid, it transports electricity across great distances. And everything you're talking about is an issue with any kind of production, I don't know why you're bringing it up as if it's unique to solar. If you're building a factory that needs high amounts of stable power then you plan accordingly. Doesn't change the fact that solar is a useful way to generate electricity. I don't thin…

Lots of probs with existing grid . Certain routes are already overloaded/congested, building new ones is not as easy because of land acquisition costs compared to the past. Repairing, upgrading and maintaining old routes to handle new loads raises costs of moving electrons to your factory etc. One hurricane or blizzard can shut a route down so redundant routes have to be built. People just under estimate how complex things have become.

Re: Solar Energy Saves Europeans $135M a Day

#146

Post by eqvinox »

gritzko wrote: post #38
ndhbxyd wrote: post #22

Earlier quoted context omitted.

It will happen when we have better weather forecasting models. If it gets randomly cloudy for 5 days this month and 17 days next months screws up planning for factories, farms, datacenters etc.

I always post this https://www.rte-france.com/en/data-publications/eco2mix/powe...

France is notorious for being all-in on nuclear, which they then have to shut down in the summer because the river water they use for cooling gets too hot.

Re: Solar Energy Saves Europeans $135M a Day

#147

Post by thelastgallon »

gritzko wrote: post #38
ndhbxyd wrote: post #22

Earlier quoted context omitted.

It will happen when we have better weather forecasting models. If it gets randomly cloudy for 5 days this month and 17 days next months screws up planning for factories, farms, datacenters etc.

I always post this https://www.rte-france.com/en/data-publications/eco2mix/powe...

The French seem to have some cool ideas to solve pesky problems. Guillotine for the super rich, nuclear for energy. Though it looks like they stopped doing both.

Re: Solar Energy Saves Europeans $135M a Day

#148

Post by tzs »

ramesh31 wrote: post #83
toast0 wrote: post #79

Earlier quoted context omitted.

Why do you need to assume 100% generation??? It's all about the all-in cost of the system vs the reduction in utility bill. If your system runs 20% of your usage, it still has whatever ROI it has. Building to cover 100% usage isn't a typical goal if you're planning to keep the utility anyway. Most net metering doesn't pay you if you make more than you use, so if you go over, you spent too much on your system.

>Why do you need to assume 100% generation For the time to payback to be even remotely close to 5 years in that scenario. Otherwise you're easily talking a decade plus.

That makes no sense whatsoever. Thought experiment:

Household #1 uses 7 kWh of electricity per day. They install a solar + battery system that produces 7 kWh per day, covering 100% of their use. This costs them $C, and the reduction in the amount of electricity they use from the grid will save them enough to break even in 5 years.

Household #2 uses 14 kWh of electricity per day. They also install a solar + battery system that produces 7 kWh per day, which covers 50% of their use. This costs them $C, and reduces the amount of electricity they use from the grid by 7 kWh per day, just like household #1. Therefore it should take them 5 years to break even, just like household #1.

Breakeven time is a function of cost and the amount your grid usage goes down. How much electricity from the grid you use if your solar system cannot supply 100% of your usage should be irrelevant to the payback time.

Re: Solar Energy Saves Europeans $135M a Day

#149

Post by Garlef »

cubefox wrote: post #121
Garlef wrote: post #99

Earlier quoted context omitted.

Er... No? Electricity prices in Germany are lower than last year. https://www.zeit.de/wirtschaft/energiemonitor-strompreis-gas...

I mean higher than in other countries with less solar energy, like France, which has mostly nuclear.

This seems to be a good question for an the LLM of you choice. I've asked one and after some search:

Wholesale prices:

- Germany ~€0.089/kWh - Factor 2.94 to consumer Price

- France ~€0.061/kWh - Factor 2.92 to consumer price

- Spain. ~€0.065/kWh - Factor 2.82 to consumer price

The reason seems to be that this price is driven by the tech that is used to fill the gaps what demand is high.

And coal/gas make this expensive.

- Germany needs a lot of coal/gas at some times

- France has nuclear so less coal/gas is needed

- Spain just has a lot of renewables and needs way less coal/gas to compensate

So France is better off because of nuclear... But Spain is doing nearly as well with renewables.

Re: Solar Energy Saves Europeans $135M a Day

#150

Post by cubefox »

ben_w wrote: post #138
cubefox wrote: post #137

Earlier quoted context omitted.

The marginal generator is likely so expensive because solar was used to replace cost effective nuclear and coal plants.

https://en.wikipedia.org/wiki/Levelized_cost_of_electricity#...

That's nonsense. Solar during overcast days is extremely and at night infinitely expensive by itself. You can't just take some average, you have to take expensive gas or battery backups into account when comparing to a stable energy source like nuclear or coal which doesn't need these backups.
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