Why should it make no sense? The feed-in tariff just about covers the investment costs.
Actually, you already answer the question in the following sentence. Monetarily, it probably doesn’t make sense at the moment. The system may pay for itself through the feed-in tariff, but only if repair costs are not taken into account. On the credit side, there are also profits from self-consumption. However, this is offset by several disadvantages that are not so easy to quantify objectively and that everyone values differently: appearance of the system – disposal problem – resource waste during production – social and ecological situation in the manufacturing country
For self-consumption, the following assumptions:
- typical builder is a couple in their mid-30s with 2 children
- parents fully employed in regular shifts
- no electric car
- no air conditioning
For us, it looks like this:
- cooking only sometimes in the evenings on weekdays
- washing and drying is done when the children are asleep
- when washing and drying is done, it’s done a lot at once
- on weekends we are not often at home during the day – either shopping or going on trips, so energy consumption is again concentrated in the evening
- sauna is only turned on in the evening
- lights are only turned on in the dark
We have 4 refrigerators/freezers (I am a hunter), these would probably be the only significant base load in our example. Otherwise, I tried to estimate what we manage in self-consumption. I actually wanted to justify a battery system. But it didn’t work out, and I think most households are structured similarly.