Photovoltaic system: Advantages and disadvantages, experiences, worthwhile?

If you then pay 200-400€ annually for it, you can calculate the difference and evaluate how small or large the difference is for you. Many people, for example, like to have the accounting done by the tax advisor, so you can really save yourself the trouble.

Tax consultants are, of course, a waste of money. Although, tax consultants are probably used less for VAT returns than for profit determination, and thus in both cases.

How do you come to €400 VAT?

Sorry, error in thinking 1-200€

How do you achieve 50% self-consumption without a battery?

50% self-consumption without storage is quite high. With a south-facing system, we have about 30%. In addition, we try to run heavy consumers like the washing machine or dishwasher at midday whenever possible. It gets a bit better with east/west systems, as more power is available in the morning and evening. However, the energy/performance of E/W systems is worse than with S systems.

Our architect said that the performance over the day is roughly identical.
With a south orientation, you have a better peak, but you also have to time all the devices (more effort?), and the efficiency decreases because the modules get warmer.
With east/west, energy is provided when it is needed, and even though the peak is not as high, the power supply is more consistent.
One could aim for an intermediate solution here, for example, by using a battery that charges over midday and then powers all the devices in the evening.
Or photovoltaic panels on three roof sides without changing the size of the system? Does that make sense effort-wise if you stay under 10 kWp?

If you have a tent or flat roof i.v. with SE yes.