Bauhaus concrete villa with core insulation - experiences

In photovoltaic systems, there is a 70% regulation or active power reduction.

Yes, but: what is the point of that?
A four-cylinder engine is enough for me, so I drive a four-cylinder. Why should I buy a six-cylinder from the car dealer and then tell him to turn off two cylinders? – I don’t understand this point: to dimension a system from the start at 40% over demand and then limit the excess; you might as well just leave out the excess (?)

Yes, but: what is it supposed to be good for?
A four-cylinder is enough for me, so I drive a four-cylinder. Why should I buy a six-cylinder from the car dealer and then tell him to switch off two cylinders? - I don't understand this point: designing a system from the start to be 40% oversized and then cutting off the surplus; you might as well leave out the surplus (?)

Wrong thinking. The more photovoltaics are installed overall, the more electricity is available even at times when the sun is not shining at its maximum and the yield is lower. That is obviously what you want.

At maximum sunlight, preferably nationwide in Germany, the grid could have problems if all photovoltaic systems run at maximum power, so the maximum production is limited here.

Certainly to still have a good yield on not so sunny days because then more modules generate more electricity than fewer

Haha Tego12 was faster^^

Alternatively, you can also have yourself regulated externally. This is mandatory above a certain level of performance; below that, it is, in my opinion, uneconomical.

Yes, but: what is it good for?

It is the lesser evil. Officially, it is about grid stability and avoiding high peaks, but in my opinion, it is simply a result of lobbying.

Since 2012, the Renewable Energy Act requires that even small systems <30 kWp must be grid-service controllable. However, the ripple control receiver (RSE) usually used for this and the additional effort in the household installation greatly impair the economic viability of such small systems. Therefore, there is the alternative to limit the feed-in fixed at 70% of the generator capacity at the inverter ("70% hard" in photovoltaic jargon). That means 30% of the generator capacity is flat-out thrown away. Alternatively, there is the possibility to implement "70% soft." In this case, the current household consumption is measured additionally, so that the photovoltaic system feeds in the "hard" 70% generator capacity plus the current consumption of its own household. Less production is wasted then.

research86 rightly noted that with an east/west system, the 70% soft regulation is usually not necessary at all, since this type of system does not deliver high peak power anyway. The south system has a strong peak at noon, whereas the east/west system shows a flatter power curve over the day. flatten the curve If you orient a 10 kWp system to the south, as a simplified example, 10 kW can come from the roof at noon; with "70% hard" only 7 kW would be allowed to feed in. With east/west, you also have a 10 kWp system, but 5 kWp are oriented east and 5 kWp west. Thus, you never reach the allowable 7 kW feed-in power.

With maximum solar radiation, preferably nationwide in Germany, the grids could have problems if all photovoltaic systems are running at maximum capacity, which is why the max. production is limited here.

I have not yet experienced a record-breaking summer when the electricity consumption for air conditioners, fans, etc. did not also rise along with the temperatures.

Officially, it's about grid stability and avoiding high peaks, in my opinion this is simply a result of lobbying.

That seems more plausible to me. It’s not clear to me why grids should handle the phenomenon of the "roast goose peak" on the supply side worse than on the demand side. After all, solar radiation does not increase suddenly either; temperatures rise predictably with several hours' lead time.