PV system for the whole roof or better to undersize?

  • Erstellt am 2024-05-02 22:12:14

Teryamy

2024-05-03 07:29:29
  • #1
30% for a system on average. The first 2 kWp certainly 80%, the last 2 kWp rather 10%. When you only get back what you originally put in, nothing is amortized for a long time. For that, you still need an interest rate. The statement "if nothing breaks" says the rest. To the OP: I would decide now based on gut feeling; this is not an investment decision but a pure consumption decision. Considering effort and structural risks, an ETF is always better. But 4,000 euros is rather pocket money, your retirement provision will not be ruined by it or exactly the opposite.
 

RotorMotor

2024-05-03 07:49:40
  • #2
Wine feeding remuneration and self-consumption should together amount to 500€/year.
Amortization period thus at just 8 years!
Which system surely achieves such a return?
[Etf] can only be meant as a joke.
 

Zaba123

2024-05-03 08:16:02
  • #3
That may theoretically be true, but you also don't calculate that over 20 years without photovoltaic, you miss out on x€ monthly due to your higher grid consumption, which you could, for example, invest in ETFs with a 7% return. For example, I would have to buy an additional 5000 kWh per year from the supplier without photovoltaic + storage, since my consumption averages 6800 kWh over 5 years. However, for me, it is not about pros and cons or squeezing out the last penny. I enjoy my photovoltaic system just as much as e-mobility.
 

kbt09

2024-05-03 08:56:27
  • #4
And, what does amortization actually mean in this context? The electricity consumption of the grid operator does not amortize either.

My experience with ONLY a small balcony power plant is that you also engage more intensively with your own habits. So currently, I not only do not purchase electricity from the grid operator that I produce myself and do not feed in, but overall, I have examined and adjusted my electricity consumption and my habits in this context, and as a result, in addition to the 460 kWh of self-consumed electricity, I do not consume more than another 100 kWh of electricity at all. It's peanuts, as it is only a rental apartment, but overall helpful. Why less? Because I have dealt with the various ECO modes of the devices, and meanwhile accept that devices sometimes run longer, etc.

In 2004, in my first year of working from home, I still consumed about 4000 kWh.
Then gradually worked it down to about 2100 to 2200 kWh.
For the billing on 30.04.2023, it was still about 1760 kWh. At that time, the BKW had been running for 6 months
And for the current billing, I have just reported about 1470 kWh.

I have not changed my end-user devices themselves.
 

RotorMotor

2024-05-03 09:27:37
  • #5
That is nonsense. Of course, you can calculate the amortization of photovoltaic systems. It is not fundamentally about the electricity itself but whether I have to buy it or generate it myself. And the feed-in tariff applies to that. In this case, something around 10 years comes out. Depending on whether you consider interest for borrowed capital or rising electricity prices or not. That is a very good return, especially with the high security. Yes, the effect you described is often present. But it has nothing to do with the question. This was about whether 6 or 10 kWp are installed. That has little influence on consumption. Sometimes even a bit the opposite, because with 10 you might even become more wasteful. But let's just stick to the numbers above, instead of feelings and behaviors; that way we are on the safe side.
 

Evolith

2024-05-03 11:17:38
  • #6
We installed our system on the roof over 2 years ago. 10kwp. We did NOT fully utilize the roof but based it on our consumption (6500kwh, heat pump, lots of home office and 4 people). For half a year now, a Tesla has been parked in front of our door, which is occasionally charged via socket due to lack of a wallbox. Conclusion: We should have fully used the roof! We will eventually do that too. In summer, we are almost continuously 100% self-sufficient. That's an awesome feeling! Even when the eDose is connected, we still feed in electricity. In winter, though, it changes drastically and we usually just manage to cover normal household needs (cooking and heating up the heat pump do the trick). We have almost halved our electricity demand. So only half the electricity costs plus now 1000€ feed-in tariff for 2 years. So fill up the roof. 6kwp is nothing.
 

Similar topics
12.02.2015Photovoltaic systems & storage systems *collective thread*21
13.07.2016Photovoltaic storage - experiences? Tips?17
17.05.2017Photovoltaics initially without storage54
20.10.2017Roof with photovoltaic or other investment, any experiences?19
05.03.2018Photovoltaic planning - possible retrofitting of battery storage13
19.02.2018Additional Costs Statement - How should the list be created?21
19.06.2018Photovoltaic system in new construction: Would you install one? Any experiences?31
24.11.2019Fuel cell or operating costs, photovoltaics and solar thermal?21
20.11.2019Photovoltaic system that pays for itself monthly and amortizes41
02.03.2020Is a photovoltaic system also sensible in the west or east?78
10.11.2021Photovoltaic system: Costs, saving potential? - Experiences?240
18.12.2020Install photovoltaic power storage yes or no?53
27.12.2020Solar Thermal vs. Photovoltaics13
31.01.2022Consultation for photovoltaic systems227
27.10.2021Photovoltaic system 120 sqm living area - cover the entire roof?45
24.02.2022Photovoltaic system air-water heat pump - profitability single-family house KFW55EE95
08.05.2023Evaluation of Photovoltaic Offer and Components34
27.09.2024PV system offer including storage - Storage yes/no?44
28.09.2024Single-family house photovoltaic system with 30KW20
02.06.2025Help with photovoltaic decision41

Oben