ᐅ Evaluation of Solar Power System Proposal with Battery Storage

What appliances do you use in the evening and how much energy do they consume? With lights and the TV, you might use about 1 kWh. The dishwasher is also in that range if you run it in the evening. The main energy consumer at night is cooking, where you often have the issue that the induction stove draws more power than the battery can supply, so you sometimes have to draw electricity from the grid. You will only consume around 10 kWh overnight if the heat pump is heating. In winter, however, you often won’t reach that amount. The battery cycles are recharged during transitional seasons when there is more sunlight but the heating still runs.

WilderSueden schrieb:

What appliances are you using in the evening and how much do they consume? With lighting and the TV, you might use about 1 kWh. The dishwasher is also in that range if you run it in the evening. The main energy consumer in the evening is cooking, where you often face the problem that the induction cooktop draws more power than the battery can supply, so you sometimes have to draw from the grid again. You’ll only use around 10 kWh overnight if the heat pump is heating. In winter, however, you often won’t fully use that capacity. The cycles are replenished by the battery during transitional seasons when there is more sunlight but the heating is still running.

I find it hard to say at the moment because my living situation is completely different and I’m not connected to a single meter. It really only makes sense when using the sauna or if the heat pump needs to heat a lot. So, you mean I probably won’t get enough cycles?!

It also depends on the current cost of the storage system.
If it only accounts for about €4,000 of the total price, it can be worthwhile.
If it accounts for about €10,000 of the total price, the situation looks different.

I firmly believe that our storage system will pay off over time.
Whether that will actually be the case, I will find out in a few years 😉

DaGoodness schrieb:

It also depends on the current cost of the storage system.
If it makes up about €4,000 (around $4,400) of the total price, it can be worth it.
If it’s about €10,000 (around $11,000) of the total price, the situation looks different.

I firmly expect our storage system to pay off over its lifetime.
Whether that really will be the case, I’ll only find out in a few years 😉

Ok, costs without storage have been requested, I’m curious :-)

Dachshund90 schrieb:

It’s hard for me to say right now because the living situation is completely different, and we aren’t connected to a single meter. It’s really only worth it when using the sauna or if the heat pump needs to heat a lot. So, do you mean I probably won’t get enough cycles?!

We haven’t had our storage system for very long either. So far, it’s almost always been nearly full because there’s simply not enough usage in the summer.
The same applies to the sauna as it does to the induction stove. If the sauna heater draws 8kW, that overloads most storage systems. However, a larger storage system does allow for a higher discharge current. But if you belong to the group that only uses the sauna in winter, the question is irrelevant anyway, since the electricity consumption of the heat pump and sauna far exceeds what the storage system can handle.

We recently installed a very similar system, also all from Sungrow.
However, ours has a 12.8 kWh battery (one module more) and 12.45 kWp.
So far, we are very satisfied with the system. We had to restart it once because it occasionally went offline for a few minutes, but it has been fine since then.
We also have a Sungrow wallbox.
In total, including installation and commissioning, we paid 26k, which I found quite reasonable compared to other offers. We got a bit of a discount, probably because the electrician who was already working on our house did the installation.

I think the offer you have is quite good in terms of price.
We were also advised against the battery. A battery is basically always a gamble on the future. You need to decide what you think is likely.
We planned based on rising energy prices and hope the battery won’t fail on the day the warranty expires.

Most days in autumn, we are about 90% self-sufficient and have even reached 100% once. That’s pretty cool. But we have a high electricity demand. We have many energy consumers in the evening (gaming PCs), a heat pump, an electric car, generally a large house, and always people working from home. We use as much solar power as possible directly during the day, but the battery still empties overnight.
Take a look at your nighttime electricity consumption to see if you can fully use the battery’s capacity. If you don’t cycle it regularly during the year, a battery rarely pays off.

Best regards,
kati1337