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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

#151

Post by kragen »

slow_typist wrote: post #134
elashri wrote: post #93

Earlier quoted context omitted.

Yes there are many studies that did life cycle assessment of them. This is a good source [1] that analyze about 400 of these life cycle assessments. [1] https://docs.nrel.gov/docs/fy13osti/56487.pdf

That is more than ten years old, efficiency of PV is much better today, which probably brings emissions down a bit.

Efficiency has improved somewhat, but also, the cost to manufacture PV is enormously lower than it was then, which means that it's using much less materials and energy to produce. Therefore the energy payback time should be much shorter.

Re: Germany outfitted half a million balconies with solar panels

#152

Post by kragen »

oceanplexian wrote: post #120
Kim_Bruning wrote: post #27

Earlier quoted context omitted.

I just did some modelling with the help of claude (which can write 200LOC+ numpy code faster than I can) 300 Euros crappy setup, 600 euros mid-range setup, 1200 with storage. (Extra) regulations is zilch, it's legal to plug and play these things up to 800W nameplate capacity. I went with numbers for mid-range, vertical south orientation and offsetting 200W (without battery, any overproduction is wasted). This nets yo…

I built one in Utah which is the only part of the US where it's currently legal, so I can give you the numbers. - 4x Hyundai 435W Solar Panels @ 167$ each for $670 total - 1x EcoFlow Stream Microinverter for $257. - Various cables, MC4 crimping kit, etc.. about $150 Grand total was $1077, I set them in direct sun on my patio and have generated 6-8kWh per day. At Utah energy prices (0.12 where I live), they will pay o…

That's fantastic! What's the microinverter's peak capacity?

Re: Germany outfitted half a million balconies with solar panels

#153

Post by morshu9001 »

lucb1e wrote: post #12
lm28469 wrote: post #2

I'm in Germany and keep seeing these, I always wonder what a 400w poorly oriented panel getting like 3 hours of sun a day is good for. If they weren't basically free thanks to tax reduction and other tricks I assume no one would get them

Article cites manufacturers as saying that > installing a couple of 300-watt panels will give savings of up to 30% on a typical household’s electricity bill, but there are lots of variables that come with that claim. It depends on which direction the balcony faces and whether the panels are shaded part of the day. My german electricity bill is around 1200 euros a year. Sign me up for a one-time purchase of 426€ to sa…

Have to also consider the opportunity cost of that upfront cash. Those numbers sound worth anyway, but the 5 year break-even mentioned in the article is more questionable, and that's with subsidies.

Re: Germany outfitted half a million balconies with solar panels

#154

Post by kragen »

pfdietz wrote: post #54
ViewTrick1002 wrote: post #34

Earlier quoted context omitted.

Yes. Phasing out coal is a multi step process. The next step is coal plants forced to become peakers thermally cycling daily because they are loosing too much. As seen in for example Australia: https://www.abc.net.au/news/2024-10-13/australian-coal-plant... The next step is being a reserve plant only activated seasonally. Finally rounding off with purely being a reserve plant and then decommissioning when it costs to…

Another possibility is retrofitting the coal plant with a thermal battery. https://www.orcasciences.com/articles/standard-thermal-copy > 3) (medium term) The world-conquering dream is for our PV-based steam to replace fossil-generated steam at conventional power plants. That will let us feed electricity back into the grid using otherwise stranded generating assets (e.g. a coal plant). You might see this as a way to c…

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.

Re: Germany outfitted half a million balconies with solar panels

#155

Post by cycomanic »

plantain wrote: post #101
Kim_Bruning wrote: post #86

Earlier quoted context omitted.

The subsidy question is interesting, but in Germany these balcony panels are ~ €600 unsubsidized (depending on the exact kit; see my numbers elsewhere in this discussion) and still pay back in 5 years. The economics work with and/or without government help.

The fact the economics of DIY make sense, is the evidence of the market/state failure. (whether they really do make sense without fanciful efficiency calculations, I leave to you). https://www.investigativeeconomics.org/p/solar-is-only-cheap...

I think you need to make some better arguments to convince. Your argument only makes sense when wholesale cost of solar panels is significantly cheaper than retail. The better the economics of scale (i.e the smaller the difference between wholesale and retail) the more favourable "DYI" becomes, because the person had home does not need to cover the overheads that are necessary for large scale installations (financing, management, transmission, planning...). It's the same reason that hiring a vps to run all your compute is not necessarily cheaper than buying your own pc.

Re: Germany outfitted half a million balconies with solar panels

#156

Post by kragen »

ssl-3 wrote: post #150
hedora wrote: post #129

Earlier quoted context omitted.

It’s not necessary in that the inverters need to support it (they could just do randomly staged power ons, and the first one could pick the phase). However, there’s a problem in addition to electrocuting utility workers (the ones around here assume islanding during outages, so that’s less of an issue now). Say you plug the microinverter into a 16A 120V outlet in the US, and the power goes out while you’re running a 2…

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.

Re: Germany outfitted half a million balconies with solar panels

#157

Post by kragen »

morshu9001 wrote: post #153
lucb1e wrote: post #12

Earlier quoted context omitted.

Article cites manufacturers as saying that > installing a couple of 300-watt panels will give savings of up to 30% on a typical household’s electricity bill, but there are lots of variables that come with that claim. It depends on which direction the balcony faces and whether the panels are shaded part of the day. My german electricity bill is around 1200 euros a year. Sign me up for a one-time purchase of 426€ to sa…

Have to also consider the opportunity cost of that upfront cash. Those numbers sound worth anyway, but the 5 year break-even mentioned in the article is more questionable, and that's with subsidies.

A 5-year breakeven for a durable good is a 20% annual return on investment, which is very good indeed.

Re: Germany outfitted half a million balconies with solar panels

#158

Post by plantain »

ssl-3 wrote: post #136
plantain wrote: post #65

Earlier quoted context omitted.

You grow herbs at home because it's kitsch, fun, or even convenient, not to save money. Store harvested herbs die in the fridge, electricity does not. In Australia, our government massively subsidizes putting solar panels on our roof, and batteries in our garages, for a $/kWh price wildly higher than could be achieved with economies of scale in an industrial installation. Batteries are even more egregious than solar,…

What does your vision of perfect solar power look like? And within that vision, is a free person still able to decide for themselves if they want to buy a solar panel to hang on their balcony?

People are entitled to do as they want, even if it's not profitable. I am just pointing out that if the economics of this add up, people have been seriously let down by their governments.

Re: Germany outfitted half a million balconies with solar panels

#159

Post by itsme0000 »

SoftTalker wrote: post #63
melasadra wrote: post #19

Some people laugh at the 800W output. However, in Indonesia, roughly half of the 300 million people live in homes with an electricity capacity of 900W or less. Wish these kind of panels were available at that price here. We have pretty much 12 hours of sunlight every single day but household solar panel is discouraged by the state owned utilities.

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[flagged]

Re: Germany outfitted half a million balconies with solar panels

#160

Post by pfdietz »

kragen wrote: post #154
pfdietz wrote: post #54

Earlier quoted context omitted.

Another possibility is retrofitting the coal plant with a thermal battery. https://www.orcasciences.com/articles/standard-thermal-copy > 3) (medium term) The world-conquering dream is for our PV-based steam to replace fossil-generated steam at conventional power plants. That will let us feed electricity back into the grid using otherwise stranded generating assets (e.g. a coal plant). You might see this as a way to c…

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.
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