The number of households in Germany operating solar panels on their balcony continued to rise rapidly since the start of the year. More than 50,000 mini plug-in PV systems usually consisting of one or two solar panels — dubbed “balcony power plants” — were registered in the first quarter of 2024, taking the total to over 400,000, according to data by the country’s grid agency (BNetzA), as seen in report from newswire dpa. In mid-2023, the number of registered systems was 230,000. The total number of these systems is likely to be higher, as many are not yet registered.
Balcony power plants are a relatively simple and affordable way for both tenants and homeowners to save on electricity costs. The grid agency simplified the registration of mini PV systems further in early April in order to allow people “to participate in the energy transition as easily as possible." Germany aims to cover 80 percent of its electricity demand with renewable energy by 2030, mainly using wind power and photovoltaics. Demand for PV systems is set to increase further this year in Germany, even if the recent boom is likely to level off because it was partly fuelled by the energy crisis exacerbated by the war in Ukraine, industry association BSW told dpa
According to a couple sites I just read, you are allowed to generate up to 600w and feed it to the grid without registering with the utility (!). [Germany & Austria] Some units are available for 300w. If the 400,000 users number is accurate, that would be, say average 450w x 400,000 = uh, carry the 1, divide by kilowatts, well, a whole bunch of watts.
I’m not sure what the consumer benefit is unless it slows down your own meter from turning, but I haven’t gotten that far.
I found a number.
“As a rough calculation, he [Jan Osenberg] estimates Germany has around 200 MW of installed balcony solar; compared to 16 GW capacity from the residential roof sector.”
Given the less than optimal environment, I would guess the capacity factor is low.
If the Germans balcony PV generate 500 watts for 6 hours per day, then they get about 3000 watt-hours per day for 6 months of the year.
Average German homes use about 4000 kwh per year = 4,0000,000 watt-hours per year
Average German homes use about 11 kwh per day = 11,000 watt-hours per day
3000 watt-hours at 30 cents/watt-hour = $90 saved per year
Data from the Energy-Charts website shows 67.44 GW of installed solar power capacity at the end of 2022. During 2023, solar generated 60,000 GWh.
60,000 / (67.44 x 24 x 365) = 0.102, or a 10.2% capacity factor. In reality, the capacity factor was even lower, since they added around 15 GW during 2023. A 10% capacity factor is pretty horrible, compared to more sunny locations. Much of the generation comes from large, utility-scale solar farms which presumably should be engineered for maximum output. So far this year, the solar power capacity factor in Germany is 2.5%! But they have yet to get to the summer months with more hours of sunshine.
The utility-scale solar power capacity factor in the US is usually around 24%.
And that’s for “well situated” locations. Balconies would be even lower because of trees and buildings. Hopefully nobody put them on the north side of buildings.
I know that Germans are not as dumb as you imply. Besides if anyone mounted solar panels on the north side of the building they would immediately relalize that solar panels need sun.
You are looking at the capacity factor for a whole year. Germans do not expect to get much solar for 6 months of fall and winter. Therefore, the German capacity factor in spring and summer is 2 x 10.2% = 20.4%. People living in the northern latitudes are happy to get their solar power in spring and summer. Northern Europeans are not competing with California, Arizona, New Mexico, Texas and the other southern states that have so much sunshine ready for solar panels.