Newly built single-family house KfW55 standard - How to heat?

We were told that with a too large photovoltaic system you overproduce and that this is basically lost when the storage is full (especially in the warm months). Also, I once read somewhere that the ratio of battery storage to photovoltaic should be approximately 1 kWp = 1 kWh. So should you rather go for a larger photovoltaic system?

What should be lost there? Everything you don't consume you even get paid for! Unless you take such a stupid storage subsidy where you have to throttle at 50%. Also consider that a larger system delivers more energy even in low light conditions and thus increases your self-consumption rate. This is especially important in winter.

I would save the money for the storage completely and rather max out everything possible; in a few years V2H/V2G will come and then you will have your storage in the car with significantly more capacity.

We were told that with a photovoltaic system that is too large, you overproduce and that is basically lost when the battery is full (especially in the warm months). Also, I once read somewhere that the ratio of battery storage to photovoltaics should be about 1 kWp = 1 kWh. So should you rather go for a larger photovoltaic system?

Ratio photovoltaics to storage: photovoltaics >= storage, better if "larger" "Overproduction": There are actually 2 kinds ... Instead of the 70% max feed-in of the power, you have 50% thanks to a subsidy. That concretely means that with 10 kWp on the roof you may feed in a maximum of 5kW to the utility. You have to consume 5kW in the house (heating, oven, stove, hairdryer, etc.) and/or charge your battery with 5kW ("soft setting"). You can only do this until the battery is full. If that is the case and you cannot absorb 5kW, the inverter throttles the power and not 10kW are "produced", but only 7kW. In this case, you lose 3kW of power. Or, you have 9kWp installed on the roof, but your inverter can only deliver "8kW" AC power. The delta of 1kW sometimes is lost %. Now, you don’t have 100% sun and an ideal curve every day ... so you can calculate a small % rate online how many € are lost per year. A somewhat undersized inverter has better efficiency at partial load (i.e. when it is cloudy). There are forums on the internet where this is discussed extensively ...

Unless you take such a stupid storage subsidy where you have to throttle at 50%.

Don’t you have to do that as well if you want a subsidy without storage?! At least that was the case last year.

I would save myself the money for the storage completely and rather fill up everything that’s possible, in a few years V2H/V2G will come and then you’ll have your storage in the car with significantly more capacity.

You probably mean decades. Sorry, but V2H/V2G is all just pipe dream.

Don't you have to do that as well if you want funding without storage? At least that was the case last year.

I don't know of any current funding that doesn't also require storage, otherwise the 70% rule applies to everyone.

You probably mean decades. Sorry, but V2H/V2G is all pipe dream.

I'm not so pessimistic, e3dc is currently leading the way and the ID3 is supposed to be able to do it theoretically as well (or all those Asian cars). If we take the energy transition seriously, we can't avoid understanding the e-car as a grid-friendly element. I think what's missing at the moment is just the political will and not the technical possibility. Sorry 4 OT