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Germany outfitted half a million balconies with solar panels

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Re: Germany outfitted half a million balconies with solar panels

#171

Post by zevon »

55555 wrote: post #146
adrianN wrote: post #72

Earlier quoted context omitted.

What a ridiculous take. I have one of these systems and a 2kWh battery attached to it. It reduces my electricity bill by about half and will pay for itself in less than five years. I sacrifice nothing of my balcony, the panels hang outside.

Can you break down the costs and subsidies you had? Genuinely curious

Not the person you are replying to but my four panels with about 2000W cost me about 370€ shipped including an inverter and cables.

The main subsidy is that you don't pay VAT. There are some smaller subsidies but they are local and come from the town/region you live in (none available in my area, for example).

Re: Germany outfitted half a million balconies with solar panels

#172

Post by kragen »

pfdietz wrote: post #160
kragen wrote: post #154

Earlier quoted context omitted.

While I think what Standard Thermal is doing is very interesting, and in particular may be very helpful for already-built thermal plants, I don't think they've solved the fundamental problem that large heat engines are really expensive to build compared to solar.

But that's not a problem they're trying to solve, or one they need to solve.

As I understand it, their market is dependent on it. They can't store electrical energy, only thermal energy, and their system is designed to store it at fairly high temperatures (they don't say explicitly, but I'm guessing 800° and up from the problems they report having to solve) which you can avoid doing if you're just targeting the process heat market. So turning their stored heat back into electrical energy is necessary for their process to make sense, and that requires a heat engine, such as a steam turbine.

But utility-scale steam circuits cost more per watt than solar panels, and much more than batteries, the electrochemical kind.

Re: Germany outfitted half a million balconies with solar panels

#173

Post by kragen »

slow_typist wrote: post #148
kragen wrote: post #112

Earlier quoted context omitted.

No, land is not a significant cost, not even in Germany. You're in completely the wrong order of magnitude.

You don’t want PV to crowd out local food production though, land is generally overused in Germany and the pressure is rising.

That could start happening if Germany's electrical energy consumption were to grow 100× or so, yeah. That might sound like I'm being sarcastic, but no, cheaper forms of energy tend to lead to more energy usage, and solar energy is cheaper, so we might see a lot more energy usage. But we're talking about problems we'll have in 20 years after we've solved global warming.

Re: Germany outfitted half a million balconies with solar panels

#174

Post by ssl-3 »

kragen wrote: post #156
ssl-3 wrote: post #150

Earlier quoted context omitted.

Even in that weird non-existent corner case instance, it is a necessary function because a hypothetical microinverter is completely and utterly incapable of kickstarting a grid.

You could totally have half a dozen microinverters scattered around your household, connected to each other but temporarily not to the neighborhood distribution network.

I could have that; many homes in the world do have that. And when the grid dies, the microinverters all die with it.

Re: Germany outfitted half a million balconies with solar panels

#175

Post by john61 »

I have cut my warm water costs by 80% with balcony solar panels. I have a warm water heating pump with 600 W electrical power. My little server turns it automatically on when the solar access power is greater than 540 W (measured by the smart meter). This generates usually enough warm water for our household. Also the solar panels cover to idle power of the house of 50-100 W very easily during daytime. This pays off in a few years and it reduces my carbon footprint and that of my neighbors.

Re: Germany outfitted half a million balconies with solar panels

#176

Post by onli »

dmix wrote: post #70
syntaxing wrote: post #48

AP News had a great article about this. We really need more states to adopt this beyond Utah. https://apnews.com/article/balcony-plug-solar-climate-energy...

> The $2,000 plug-in solar system installed on Dwyer’s backyard deck in March consists of two 400 watt panels, an inverter, a smart meter and a circuit breaker. It saves him around $35 per month on his power bill because he is consuming less energy from the grid, but he said reducing his carbon footprint was his primary motivation. so about 5yrs ROI And in germany a similar 5yr ratio (With some german cities subsidiz…

It's nice that it is both. You do something good and also save money. Everyone with a plug at their balcony is throwing money away when not installing some panels, if there is no roof installation already ofc.

Re: Germany outfitted half a million balconies with solar panels

#177

Post by adrianN »

slow_typist wrote: post #145
adrianN wrote: post #76

Earlier quoted context omitted.

It is completely rational to install one of these. The paypack times are just a few years, depending on how sunny the balcony is.

Well not if you value the time you put into the project, that can easily double or triple the payback time.

It takes literally two hours to install and plug it in if you have two left hands like me.

Re: Germany outfitted half a million balconies with solar panels

#178

Post by brucehoult »

tecleandor wrote: post #50

> German regulations limit balcony solar systems to 800 watts, enough to power a small fridge or charge a laptop. That gotta be a big laptop!

Yeah, crazy.

I've got 6x 440W panels literally lying flat on the lawn. They produce at least enough (200W) to power all my computers, my Starlink, my fridge, and some LED lighting by about 2 hours after sunrise and until 2 hours before sunset, even if it is completely overcast and/or raining. When there isn't a cloud in the way they produce 2000W-2400W from 11 AM to 3 PM, usually enough (at this time of year, spring conditions) to fill my 6kWh battery by noon if I don't need to use it for heating (4kW output portable air conditioner, using 900W) in the morning, leaving the electricity free for cooling in the afternoon. Otherwise the battery fills in the afternoon. If I don't need heating at night then the battery powers everything from before sunset to after sunrise with typically 2-3 kWh left in the morning to make coffee and breakfast (I use about 1kWh in the kitchen per day) and run some heating until solar generation (and the direct sun heating) pick up.

The solar panels (JAM54D40-440/GB if anyone is interested) cost me the equivalent of US$390 plus tax for all six. The Pecron E3600LFP I use to control them (combined 3kWh battery, 2x 1200W MPPT controllers, 3600W inverter, AC charger) cost ~US$1500, and an extra 3kWh battery US$800. And $200 for 2x 30m 6mm^2 cables. That's it.

I just did this last month. Results so far indicate the panels will pay for themselves by March. I bought the battery unit primarily as a UPS because of the terrible electricity reliability where I'm living, and a $450 petrol generator to charge it in the event of the multi-day outages I get in big storms (most recently 40 hours in April). It was looking like having about an eight year payback period just via time-shifting night rate power to peak times, but adding the solar panels looks like reducing that to about three years.

I'm at 35.5º S.

Re: Germany outfitted half a million balconies with solar panels

#179

Post by kragen »

AtlasBarfed wrote: post #167
kragen wrote: post #147

Earlier quoted context omitted.

Well, there really are economies of scale involved in building solar farms. Accidental deaths per installed megawatt are orders of magnitude lower than rooftop solar. A single-axis solar tracker can rotate hundreds of square meters of solar panels. Washing dust off solar panels can increase their output by several percent, but is much more likely to happen if it's somebody's full-time job instead of a household chore…

Are deaths per megawatt really better if one looks at total infrastructure deaths from transmission wires and the like?

I think the answer is that they are, because there aren't that many infrastructure deaths.

https://www.ncbi.nlm.nih.gov/books/NBK448087/ says that in the US, where the statistics are best, "electrical injuries cause approximately 1000 deaths annually. Of these, around 400 result from high-voltage electrical injuries, while lightning accounts for 50 to 300 deaths." That's 400 deaths per year from high-voltage transmission lines and substations, and from other high-voltage sources such as CRT televisions being repaired or ion-implantation voltage sources. https://en.wikipedia.org/wiki/Electricity_sector_of_the_Unit... says the USA's utility-scale electricity generation was 4230.723 TWh in 02022.

So that's ballpark 100 nanodeaths per megawatt hour from transmission wires and the like. Or 0.1 deaths per terawatt hour. By contrast, https://www.nextbigfuture.com/2008/03/deaths-per-twh-for-all... claims that rooftop solar claimed 0.44 deaths per terawatt hour at the time; possibly that has improved since then, but I doubt that it has changed that much. Brian Wang returned to the question in 02021 in https://www.nextbigfuture.com/2021/07/2020-fatalities-for-us... and estimated almost 1 death per terawatt hour.

So it seems clear that the infrastructural deaths are much lower than the deaths from falling off roofs.

Re: Germany outfitted half a million balconies with solar panels

#180

Post by adrianN »

ffsm8 wrote: post #114
kragen wrote: post #102

Earlier quoted context omitted.

Yes, but until recently, Germany produced more electricity than China did.

You're not getting his point. Germany has a space problem. There aren't large swaths of land available to put solar panels on. Added to that you have to realize just how far north Germany is, and consequently how... Bad solar is because of that. Seriously, dropping down the same amount of panels gets you significantly less electricity in Germany then where China is building them, much closer to the equator. Overall,…

Germany uses millions of hectares to grow biofuels. They would be better used for solar panels, but NIMBYs prefer endless monoculture.
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