ᐅ Photovoltaic System – Is It Worth It?

Hello dear community! I’m new here. My girlfriend and I want to renovate my parents’ house instead of building a new one. Sustainability has also become an important topic in this project. We are considering installing a photovoltaic system. Does anyone have experience with retrofitting one? Would it even be cost-effective? And what are the requirements regarding this in Austria? I hope you can help us!
Best regards, felixdummy

felixdummy schrieb:

Would it even be profitable? And what are the regulations regarding this in Austria? I hope you can help us!

In Germany, this question doesn’t really arise due to the feed-in tariff system. Austria is a bit different. The answer depends, and it’s not entirely clear. Unfortunately, I’m not familiar with the exact framework for feed-in tariffs there, but I assume it is simply compensated at around 5ct/kWh.

Since the levelized cost of electricity from a small photovoltaic system is above 5ct/kWh, it mainly makes sense economically through self-consumption. This also depends on whether you use a heat pump or something else for heating.

With a 6kWp system in Austria, and a suitable orientation, you can expect an annual yield of more than 6600kWh (kilowatt-hours). Of that, you can consume about 2200kWh yourself and would need to sell around 4400kWh.
So, for the electricity sold, you would receive about 220€/year.
For simplicity, I assume a very low grid electricity cost of 15ct/kWh.
This means you would save more than 330€/year through self-consumption.
In total, that adds up to annual savings of about 550€/year. The system’s lifespan is over 20 years, so that means at least 11,000€ in savings/revenue. The system itself should be achievable for about 8,000€. So overall, a positive calculation. However, it should be expected that within 20 years you might have to replace the inverter for under 1,000€. On the other hand, the modules usually last significantly longer than 20 years.

The calculation assumes there is a feed-in tariff. If there isn’t one, it becomes difficult with a grid electricity price of 15ct/kWh. If your electricity price is around 20ct/kWh, then the system is profitable through self-consumption alone.

If you use a heat pump, your self-consumption would be somewhat higher, which increases the benefit of the photovoltaic system. If there is a difference of more than 15ct/kWh between feed-in tariff and grid electricity costs, then it makes sense to carefully calculate the benefit of adding a battery storage system.

If you plan to use an electric car within the next 10 years, this would increase the economic efficiency (self-consumption) of the photovoltaic system.

By the way, I couldn’t understand why it should make a difference whether the photovoltaic system is installed in an existing building or in new construction. Maybe there is something specific in Austria regarding photovoltaics in new buildings (such as subsidies?).

Best regards
gnika77

Photovoltaic systems are only worthwhile, if at all, without storage. However, it should be noted that only a high energy consumption makes them profitable. They are quite practical when combined with a heat pump and an electric vehicle.

In Germany, it is always worthwhile as long as there is no shading and you do not buy from the pharmacist. It pays off solely through the 20-year guaranteed feed-in tariff. Self-consumption is the icing on the cake.

Bookstar schrieb:
Photovoltaics are only worthwhile without a battery storage system.

This is only true in the case of feed-in tariffs in Germany. In Austria, or in Germany without the Renewable Energy Act, the cost of battery storage can actually be lower than the difference between feed-in compensation and grid electricity costs when there is a good offer for a battery. However, this is often still quite borderline.

Regards, Nika

In Austria, there are two incentives: a feed-in tariff of 7.67¢/kWh and an investment grant of €250 per kWp (kilowatt peak).
Electricity costs between 15 and 20¢/kWh – providers seem to vary quite a bit regionally.
This makes it clear that self-consumption is more worthwhile than feeding electricity back into the grid.
In winter, you need more electricity than in summer, while the photovoltaic system produces more electricity in summer than in winter. Oh, and it produces more during the day than at night, which is a good reason for a battery.
If you can cover 2000 kWh of self-consumption at 15¢/kWh, you save €300 annually; at 20¢/kWh, it’s already €400. You can earn a little more from the surplus production in summer. These are just examples; make a calculation based on your own consumption pattern.
You can then compare the purchase price minus the subsidies and calculate after how many years your savings will exceed the investment, possibly including financing costs.
You can also factor in price increases or alternative system options, but you don’t have to.
That’s the financial side of it.
Sometimes, it simply feels good to become somewhat more independent and have the satisfaction of doing something “right.” Some people love the technology and enjoy “playing” with photovoltaic systems. As they say in the Rhineland, everyone is different.
If the investment does not cost you essential liquidity, just go for it.