PV System Planning & Sizing
Analysis of roof area, orientation and consumption profile for optimal system design.
Photovoltaics & Battery Storage in Wels
Constant Sanitär & Elektro is your partner for photovoltaic systems in Upper Austria and Salzburg. We plan and install PV systems on pitched roofs, flat roofs and facades, integrate battery storage, and handle permits and grid connection. From first consultation and grant applications to commissioning – all from one source.
Your path to your own solar power
With a photovoltaic system you produce a large share of your electricity and become less dependent on rising energy prices. We plan and install PV systems that match your roof area, consumption and budget.
Optionally we combine your system with a battery storage so you can use more of your own electricity. We support you from planning and grants through to grid connection.
Clean solar power
From module layout on the roof to grid connection – we take care of every detail.
Service overview
What we offer
Roof Mounting
Safe installation on pitched and flat roofs with suitable mounting systems and penetration details.
Battery Storage
Selection and installation of battery storage to significantly increase your self-consumption.
Inverters & Monitoring
Integration of modern inverters with online monitoring for full transparency of your production.
Permits & Grid Access
Support with notifications to grid operator and authorities, meter replacement and commissioning.
Grant Advice
Information on current grant programmes (e.g. feed-in, Climate and Energy Fund) and support with applications.
Right-sizing your PV system
Electricity consumption → system size → storage
As a rough guide: a household with annual consumption of 3,500 kWh can generate a large share of its electricity with a system of about 6–8 kWp. Without storage you typically use 25–35% of the generated power yourself, with storage around 50–70%. System size should be based not only on consumption but also on available roof area. In Upper Austria, 1 kWp yields about 1,000–1,100 kWh per year. We calculate the optimal size from your consumption and roof area.
As of 2026. We are happy to advise you individually.
Frequently asked questions
What does a PV system cost for a single-family house?
A typical PV system for a single-family house (8–12 kWp) costs including installation approx. €12,000–€18,000. With battery storage (5–10 kWh) add approx. €4,000–€8,000. The EAG investment grant and possible regional grants reduce the cost further.
When does a PV system pay for itself in Upper Austria?
With an average electricity price of €0.25/kWh and self-consumption of 25–35% (without storage) or 50–70% (with storage), a PV system typically pays for itself within 8–12 years. The higher your self-consumption, the faster it pays off. Module lifespan is 25–30 years.
What grants are available for PV in Austria 2025/2026?
Main grants: EAG investment grant (2026: €150/kWp for systems up to 10 kWp, €140/kWp for 10–20 kWp, battery storage €150/kWh – awarded in time-limited funding calls), payment for surplus electricity fed into the grid via OeMAG or an electricity supplier, and possible regional and municipal grants. The 0% VAT rate on PV ended on 31 March 2025 – 20% VAT applies again since 1 April 2025. We help you with the applications.
Do I need a battery storage?
Storage significantly increases self-consumption (from about 30% to around 50–70%) but is not essential. Whether storage pays depends on your consumption pattern: if you are away during the day, storage is especially useful as it stores solar power for the evening. We calculate the optimal storage size from your actual consumption.
Is my roof suitable for a PV system?
Most roofs in the Wels region are suitable for photovoltaics. South, south-east or south-west orientation with 15–35° pitch is ideal. East-west roofs and flat roofs also work well – on flat roofs modules are mounted on frames. Shading from trees, chimneys or neighbouring buildings can reduce output. We check your roof free of charge on site and simulate expected yield.
Does Constant Sanitär handle permits and grid connection?
Yes, we take care of everything: checking with the municipality whether a building notification is needed, registration with the responsible grid operator, the feed-in contract for surplus power and commissioning. This keeps your effort to a minimum.
Benefits
Why photovoltaics pays off
Lower electricity costs through self-generated solar power.
Greater independence from energy suppliers and price rises.
Contribution to climate protection through lower CO₂ emissions.
Higher property value through modern energy technology.