Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Solar Energy Saves Europeans $135M a Day

cleantechnica.com

Post reply on HN
Print view View original

81–90 of 166 posts

Re: Solar Energy Saves Europeans $135M a Day

#81

Post by cubefox »

Tade0 wrote: post #61
cubefox wrote: post #47

This seems highly doubtful. If solar saves money, why does Germany (with a lot of solar) have higher rather than lower energy prices?

Partly because they still use coal, which is heavily taxed under the emissions trading scheme and partly because of the way electricity auctions work in most of Europe, namely every participant sells at the price offered by the highest bidder. Spain opted out of this system and is now enjoying cheap wholesale electricity, which is fueling an industrial revival.

> Partly because they still use coal, which is heavily taxed under the emissions trading scheme

... and solar is heavily subsidized, which could outweigh this effect. So this doesn't explain the high energy prices.

> partly because of the way electricity auctions work in most of Europe, namely every participant sells at the price offered by the highest bidder.

This doesn't explain why Germany has so high electricity prices.

Re: Solar Energy Saves Europeans $135M a Day

#82

Post by belorn »

If I look at a electricity bills the last year, consumption costs sits around 20-25% of the total (with tax). The remaining 75% is grid connection fees and infrastructure fees that pay for expansion of future transmissions. The argument why those grid and infrastructure fees exist is primarily because of the intermittence problem cause by solar and wind.

This makes calculating the cost saving from solar and wind a bit complex.

Re: Solar Energy Saves Europeans $135M a Day

#83

Post by ramesh31 »

toast0 wrote: post #79
ramesh31 wrote: post #70

Earlier quoted context omitted.

That 5 years assumes you can provide 100% of your electricity usage via solar, which is a complete fantasy outside the south/southwest US, and would realistically require a >10kw system. But again, it's also the out of pocket money we're talking about. Very few normal people can float that, and opportunity cost is real.

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.

Re: Solar Energy Saves Europeans $135M a Day

#84

Post by mayama »

outside2344 wrote: post #74
whimsicalism wrote: post #39

Earlier quoted context omitted.

batteries are not yet competitive with fossil fuel

This is not true. Batteries are cheaper than peaker power plants using fossil fuel. They also allow the operator to fulfill market demands at the minute level versus the hours previously that it took to turn on a peaker plant. This is being done at scale in California and Texas.

Fore more than 2 hours capacity, batteries are expensive than most other and cost keeps increasing as more hours of capacity needed. Without gas or coal to burn when 1hr battery capacity runs out, battery storage is expensive.

Re: Solar Energy Saves Europeans $135M a Day

#85

Post by alexey-salmin »

teiferer wrote: post #27
baq wrote: post #18

Earlier quoted context omitted.

it's a way to get infrastructure built up. the tax dollars pay for bootstrapping of the ecosystem. it's actually smart in principle if you think about it, but obviously there's room for abuse and outright fraud.

Exactly. Sadly, it gets overlooked how much subsidies nuclear and even oil+gas have received over the years. Nuclear energy wouldn't even be a thing without heavy govt subsidies. And it keeps needing subsidies. No nuclear plant is economical without subsidies. (The operators admit this themselves.) In contrast, the solar and wind industry is eventually carrying itself without subsidies. In many parts of the world tha…

The total cost of the French nuclear program since the beginning was estimated at 228 billion euros at 2012 prices, including both research and construction costs.

By that time Germany cumulatively poured around a trilling euros into the green energy and still had coal power plants and 2x the CO2 per capita compared to France.

As of 2026, in Germany 22.5% of electricity still comes from coal and CO2 per capita is still 1.7x of France.

The hard numbers so far are extremely favorable towards nuclear. Roughly speaking you get 1.7x better results at a 1/4 of the cost.

Re: Solar Energy Saves Europeans $135M a Day

#86

Post by polairscience »

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…

I'm not a six figure earner, and have never been close. Your mentality is not everyone's mentality. And there are many people, my neighbors and friends, who are willing to pay more for energy security and independence who are not in a bubble of six figure earners.

For your equity comment, it reads like astroturfing. Every single report with real-world data shows that it's positive equity and that homes with installations sell for more than those without. It's not a "vibe" I have, it's a cold hard fact. There's a million things you maintain when you own a house, and free energy is literally the easiest thing to want to maintain. Compare that to siding, or septic, or anything else....

Your comments aren't in good faith at all.

Re: Solar Energy Saves Europeans $135M a Day

#87

Post by ben_w »

inglor_cz wrote: post #45
runtime_terror wrote: post #33

Earlier quoted context omitted.

Batteries, having a mixed grid of renewables, and new advances in nuclear solves this

To scale battery storage to a level that is capable of bridging, say, 48 hours of "Dunkelflaute" (darkness and no wind) on a regional scale (e.g. the entire Scandinavia) is probably unrealistic. Just the amount of lithium needed would be insane. And there were longer Dunkelflautes in recent history. New advances in nuclear is what I hope for. First experimental SMRs are being installed in several places of the world,…

> To scale battery storage to a level that is capable of bridging, say, 48 hours of "Dunkelflaute" (darkness and no wind) on a regional scale (e.g. the entire Scandinavia) is probably unrealistic. Just the amount of lithium needed would be insane. And there were longer Dunkelflautes in recent history.

48 hours in Scandinavia is roughly equivalent to turning all their road vehicles electric. And that's even with Norway using the second highest per-capita rate of electricity in the world let alone Scandinavia (second to Iceland, whose electricity is 100% renewables thanks to abundant geothermal): https://www.statista.com/statistics/383633/worldwide-consump...

Given nobody is suggesting an instantaneous transition, this is not at all unrealistic, and I don't know why anyone might consider it to be.

Good luck with new nuclear, but with all the politics in that domain, I don't expect that to work out even if e.g. Helion Energy supplies working shipping-container-sized aneutronic fusion.

Re: Solar Energy Saves Europeans $135M a Day

#88

Post by complianceowll »

polairscience wrote: post #80
complianceowll wrote: post #69

Earlier quoted context omitted.

Uh, that's absolutely badass... As an adult, one of the things that fascinate me is self-sufficiency: the idea that you can buy a solar power system, install it, and use your own power -- without getting a bill in the mail every month, many times feeling like a victim of modern day suburban subjugation. I'm still a good little obedient peasant, but I hope one day I can rely more on well water/rain catchment system, s…

If you own a home you should genuinely spend time calculating and thinking about it. It's not near as far fetched as you think. You can benefit from the same technical advancements in engineering and manufacturing that have benefited every single industrial sector. It has never been easier. The number of plug and play components out there is unreal. These days it's very much sun-legos. You decide what you can afford…

I 100% believe you! We're planning on doing a custom build for our next home, and I'm going to budget for solar. Like you said, it's gotten so much easier these days and I think that we don't take advantage of this because it requires budgeting/saving and because paying a monthly bill can be so much easier in the short-term. But I'm 100% going to do this.

Re: Solar Energy Saves Europeans $135M a Day

#89

Post by elevation »

complianceowll wrote: post #69
tapoxi wrote: post #23

I installed a solar system at my home in Massachusetts for 17k last year (after tax credits), 7.82 kw. So far it's covered about 70% of my usage and 5.7 Mwh. I don't have a full year of data yet so I expect that number to grow as it includes the summer months. I drive an EV and this includes the car.

Uh, that's absolutely badass... As an adult, one of the things that fascinate me is self-sufficiency: the idea that you can buy a solar power system, install it, and use your own power -- without getting a bill in the mail every month, many times feeling like a victim of modern day suburban subjugation. I'm still a good little obedient peasant, but I hope one day I can rely more on well water/rain catchment system, s…

> one day I can rely more on well water/rain catchment system

There are some fascinating youtube videos on digging your own backyard shallow well (12-40'). This close to the surface, the water is considered non-potable, and you should have yours tested, but you can pump up what you need for backyard garden irrigation. Wells like this can be seasonal, as it is essential a rainwater catchment system using the permeable ground as your reservoir. Still, a neat concept for a relatively low cost.

Re: Solar Energy Saves Europeans $135M a Day

#90

Post by toast0 »

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.

I don't get it... system costs scale pretty closely with number of panels.

If a $X system covers 100% of your use, a $X/2 system probably covers 50% of your use.

Ignoring time value of money, if the $X system saves you $X / 5 per year, the $X / 2 system that generates 50% will save you $X / 10 per year. Both systems would have a 5 year ROI.

Even if your half price system generates only 45%, it only brings the ROI out to 5 years 6 months.

There's are some fixed costs to hook into your panel and whatnot, but as long as your system is within a reasonable range, the math should math pretty well until your system generates more than your usage. Assuming the math maths at all... if system costs are high and utility rates are low, it doesn't math. If you roll a roof replacement into your system cost, then yeah, a small system won't get you the ROI, but I don't think the math works to include roofing in the system cost unless your utility power is very expensive per kWh. If you're in a reasonable cost area, and you need a new roof for your system, you need to wait until it's time for a new roof anyway. Or if you can't afford a new roof and a solar system at the same time and don't want to finance the solar system, you could probably have the roofers put in rails for future panels when the roof is installed so that the roof warranty covers the rails. Then you can add solar when you've rebuilt your reserves.

Post reply on HN