A 20 kWp system is a large roof system – for a large single-family home, a home with a heat pump and electric car, or a small apartment building. As a guideline value it costs roughly CHF 34,000 to 46,000 including installation, whereby the price per kilowatt-peak tends to be lower than for smaller systems – larger systems spread the fixed costs over more output. The one-off feed-in incentive is deducted from this, which amounts to several thousand francs at this size. (As of: July 2026)
Key points in brief
- 20 kWp is a large system – for large single-family homes, households with a heat pump and electric car, or small apartment buildings.
- Guideline value incl. installation: around CHF 34,000–46,000, before incentives.
- The price per kWp tends to fall compared with smaller systems (fixed costs spread over more output).
- The one-off feed-in incentive amounts to several thousand francs at this size.
- From this size upward, it's worth looking at the self-consumption concept and ZEV.
What does a 20 kWp system actually cost?
As a guideline value, a 20 kWp system including installation costs roughly CHF 34,000 to 46,000 – before deducting incentives. The range is wide because roof type, complexity, module choice and any storage battery shift the price considerably. How the price is fundamentally made up is shown in the article Cost per kWp; the smaller siblings of this system are covered in the articles on the 15 kWp system and the 10 kWp system.
An important effect at this size: the price per kilowatt-peak tends to fall compared with a small system. The reason lies in the fixed costs – scaffolding, planning, connection, and site visits cost roughly the same whether you build 10 or 20 kWp, and are spread over more output with the larger system. A 20 kWp system therefore doesn't cost double a 10 kWp system, but noticeably less than double.
| Size | Guideline value (incl. installation, before incentives) | Price per kWp |
|---|---|---|
| 10 kWp | see 10 kWp guide | medium |
| 15 kWp | see 15 kWp guide | lower |
| 20 kWp | around CHF 34,000–46,000 | lowest in this series |
Guideline values, as of: July 2026. Actual costs depend heavily on the roof, complexity and equipment – the individual quote is authoritative.
How much one-off feed-in incentive do I get for 20 kWp?
The one-off feed-in incentive (the KLEIV for small systems) is assessed per kilowatt-peak, and at 20 kWp it adds up to several thousand francs. For systems up to 30 kWp, the higher rate per kWp applies; the exact rates and the application process are covered in the article on the one-off feed-in incentive. The rates currently set by Pronovo are authoritative.
This noticeably reduces the net costs. As always, the sequence and the correct registration matter – the one-off feed-in incentive is applied for after commissioning, but belongs in the planning from the very start.
Who is a 20 kWp system worthwhile for?
This size is made for three situations. First, the large single-family home with correspondingly large roof area. Second, the household that's deliberately expanding its consumption: anyone running a heat pump and an electric car has a much higher electricity demand than average – and for them a larger system is worthwhile because more self-consumption is possible. Third, the small apartment building, where several parties share the solar power through a self-consumption community.
The common thread here: from this size onward, it's no longer just the roof area that decides, but the self-consumption concept. A large system whose electricity flows unused into the grid at midday doesn't exploit its potential. Whether a storage battery is worthwhile is a separate calculation – the article on the solar system with storage shows the orders of magnitude. The honest sequence is: first look at consumption and its time profile, then size the system accordingly.
At 20 kWp, the conversation shifts away from pure roof area toward consumption. Anyone building this much output usually has a reason – a large house, a heat pump, an electric car, or tenants who are meant to be supplied too. And that's exactly where we start: a 20 kWp system is only as good as the concept that uses its electricity. We occasionally see large systems that feed almost everything into the grid at midday because nobody's home and no control system kicks in – a shame about the potential. What we advise everyone going into this size range: calculate the system from consumption, not from the roof. Then the size fits, and the electricity stays in the house.
Frequently asked questions
What does a 20 kWp solar system cost in Switzerland?
As a guideline value, around CHF 34,000 to 46,000 including installation, before deducting the one-off feed-in incentive. The range is wide because roof type, complexity, module choice and any storage battery shift the price significantly. The individual quote is authoritative – a figure from the internet doesn't replace a site visit.
Is a 20 kWp system cheaper per kWp than a small one?
Tending to yes. Fixed costs like scaffolding, planning, connection and site visits are similar whether you build 10 or 20 kWp, and are spread over more output with the larger system. A 20 kWp system therefore doesn't cost double a 10 kWp system, but noticeably less.
How much one-off feed-in incentive is there for 20 kWp?
Several thousand francs – the one-off feed-in incentive is assessed per kilowatt-peak, and the higher rate applies for systems up to 30 kWp. Pronovo sets the exact current rates. It's applied for after commissioning, but belongs in the planning from the very start.
Who is such a large system worthwhile for?
For large single-family homes, for households with a heat pump and electric car, and for small apartment buildings with a self-consumption community. From this size upward, the self-consumption concept is decisive: a large system is worthwhile if its electricity is actually used – otherwise it flows cheaply into the grid.
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We size your 20 kWp system based on consumption – including heat pump, electric car and the question of whether a storage battery or a ZEV is worthwhile.
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Swissolar-certified specialist company · ESTI installation authorisation (Art. 14 NIV) · in Zurich since 2017 · over 150 systems completed · a personal answer from the specialist company, no call centre
Sources: Market-standard guideline values from Swiss providers (as of July 2026), Pronovo (one-off feed-in incentive), experience from system projects by ecoEn GmbH, Zurich region.
Last updated: 9 July 2026 · Author: ecoEn editorial team
