Balkonsolar - year three in review
Thomas Hampel
19 January 2026It's been THREE years ago when I installed two solar panels on my balcony to produce my own power.
I've already blogged about it at length two years ago and again last year
Now another year has passed and I'd like to review it again with current information.
Nothing has changed the cost of power per kW stayed at € 0,35 per kWh and I did not manage to upgrade the inverter from 600W to 800W but writing this blog post serves as a good reminder.
so lets take a look 2025.
I've done the last assessment exactly one year ago, so now its time to review the third year of running my own mini solar power production at home.
Following are the plain unfiltered figures:
Produced : 580,06 kWh, so 27,5 kWh more than last year.
I've returned 101 kWh to the grid (for free) due to producing more than what I have used, mainly because I was on vacation away from home.
At a current price of € 0,35 / kWh it results in savings of € 203,02 for 2025
Which is about the same savings as the year before:
2024 = € 193,39
2023 = € 210,62
Our power cost here is slightly higher than the current market price with € 0,35 / kWh vs. € 0,30 / kWh in average.
So it is time to look for a new supplyer that providers a better price.
Lets look at the charts for the year 2025.
Please note I am including the energy I have returned to the grid worth € 35,35 in my savings calculation because it was on me to use it.
Here is the chart showing power production over the course of the year.
In this year, the month of June seemed to be the best month, but July showing a sharp drop. Overall April came out much stronger than the last two years, see yourself.
When putting all the charts together, you can see a difference due to mount panels at an angle - which I've done in 2024.
Ok, great - now what's next?
UPGRADE! This year the legal situation changed in Germany in 2024. It is now allows to run with an 800W inverter while I'm still using the basic 600W inverter.
I already bought the new inverter, but have not found time to do the upgrade. Overall I'm not expecting a huge power boost, but a small 10% to maybe 20% improvement during the peak PV season in summer.
TCO (updated)
Price for new solar panels has dropped to <50 Eur / piece for a 450 Wp panel, e.g. Trina Solar.
EUR 100,- for 2x Panels (€ 50,- each)
EUR 85,- for 1x Hoymiles HM-800
EUR 80,- for panel mount/equipment
EUR 50,- for some 5m solar power cables,adapters and other small parts
= EUR 315,-
Given current figures, the entire investment would have already payed off in under two years!.
Just because I bought my equipment at a slightly higher price, my personal return on invest was achieved in 2025.
Conclusion:
Is it (still) worth it ?
Need to repeat my previous statement from 2023 : Absolutely YES YES YES YES!
Even at current energy prices and prices of new solar panels you'll have a return of invest in under two years.
That is comparable to an interest rate of >50% - where on earth do you get that for your bank account?
My advise:
Dont wait, START NOW and install as many solar panels as you (leagally) can.
Tagged with: Solar