ᐅ Photovoltaic System – Is It Worth It?

gnika77 schrieb:
I agree with the first statement in the case of Germany.
Storage costs of over 30 cents/kWh were accurate about two years ago. That’s when I bought my battery, which cost roughly 31 cents/kWh.
Nowadays, you can get a battery storage system for under 25 cents/kWh. Depending on demand and system design, I have even seen offers below 20 cents/kWh. In 5 to 7 years, without renewable energy legislation, a battery storage system will almost certainly be cheaper than feed-in and repurchase.

Regards, Nika

Really? Do you have a calculation example for that?

I just quickly looked for a storage system on an online shop. NeeoBASIX 6.5 at €6790. Nominal capacity 6.5 kWh, usable capacity 5.5 kWh. Expected cycles 5000. That means 27,500 kWh can be charged and discharged, without accounting for storage losses or standby consumption (especially in winter). €6790 purchase price divided by 27,500 kWh results in 24.7 cents per kWh, just for the initial cost of the battery. This excludes installation and accessories. Plus about 4 cents VAT on self-consumption.

Photovoltaic electricity generation costs about 5 cents/kWh, plus storage cost of 25 cents/kWh, plus VAT of 4 cents/kWh. This makes at least 34 cents/kWh for a self-generated, stored, and later self-consumed kWh of electricity. It is obvious this is not economical, since regular grid electricity is already significantly (!) cheaper.

My suggestion:
Photovoltaic electricity generation at about 5 cents/kWh, minus feed-in tariff of 12 cents/kWh. That results in a 7 cent profit. Buying electricity back at night from the utility here costs 23 cents, which effectively means 16 cents per kWh from the so-called expensive “battery storage grid.” This is cheaper than any electricity tariff an individual customer can get.
Of course, the best option is direct self-consumption, which comes to about 9 cents/kWh including generation costs plus VAT.

gnika77 schrieb:
In 5-7 years, a storage system will almost certainly be cheaper than feed-in tariffs and buyback without the Renewable Energy Act.

That may be true, but it is not a valid argument to buy a storage system now, especially when after 10 years no one guarantees its capacity anymore. Although 5000 cycles are already quite good, and definite progress can be seen here.

As soon as the Renewable Energy Act expires, storage will be the only option if you don’t want to give away the electricity you generate to the utility company. At least based on the current situation. If politicians stay inactive here as well, the systems will be dismantled just like what’s happening now with the wind turbines. What a great energy transition.

@felixdummy: Your question was whether photovoltaic systems are cost-effective. It's difficult for anyone to give you solid advice tailored to your personal situation. Conditions can vary greatly. Look at the electricity price trends in your area over the past 20 years. Then get a quote for the simplest possible system. Estimate your future electricity consumption, try to calculate an average electricity price for the next 20 years (cautiously), and then do the math yourself.

guckuck2 schrieb:
Really? Do you have a calculation example?

I quickly looked up a storage system in an online shop. NeeoBASIX 6.5 for €6790. Nominal capacity 6.5 kWh, usable capacity 5.5 kWh. Expected cycles 5000. That means 27,500 kWh go in and out, without considering storage losses or standby power (winter time!). Dividing the purchase price of €6790 by 27,500 kWh results in 24.7 cents per kWh, just for the initial cost of the storage system. This excludes installation and accessories. Plus about 4 cents VAT on self-consumption.

PYLONTECH LiFePO4 storage 48V – 7.2 kWh for €3500.
I would say you can almost halve your calculation with that.

But these are only the pure memory cells

The problem is that not everyone has an unlimited line of credit. The purchase usually has to be paid for upfront. Especially in the case of renovating older buildings, there are often better alternative investments in insulation, heating technology, etc., which pay off much faster and provide greater environmental benefits. In particular, storage technology using lithium is an ecological disaster in terms of production.