You can recognise a good solar company by four things: verifiable reference systems in the region, a quote with all items fully itemised, its own installation teams instead of anonymous subcontractor chains – and being reachable after installation. Price and module brand matter, but they come second to these four points.
Key points in brief
- The system runs for 25 years and more – you are not choosing a supplier, but a long-term point of contact.
- References in the region say more than any website: ask about specific systems and go and look at them.
- Anyone building in Zurich needs to know the local procedures: ewz or EKZ, the municipality's notification procedure, core-zone rules.
- Beware of doorstep selling, discount countdowns and high advance payments.
- A transparency note: we are a provider in this region ourselves – the criteria in this article nevertheless apply to everyone, including us.
Why choosing the company matters more than choosing the modules
Modules today are technically mature across the board – between two solid makes, nuances decide. Between two companies, on the other hand, there are worlds of difference: planning quality, clean installation, meeting deadlines and whether anyone still answers the phone in year five. In everyday life, a mid-range system from a reliable company beats a premium system whose builder can no longer be reached.
The 7 criteria in detail
1. References in the region. Not "over 1,000 satisfied customers" on the website, but specific systems: where? How big? May I contact the owner? Reputable companies will give you two or three addresses without hesitation. How to check references without being pushy: Checking references properly.
2. A complete, specified quote. Makes with model designations, scaffolding and electrical work as separate items, registrations included. The complete checklist: Comparing quotes.
3. Own installation team or clearly named partners. Ask directly: "Who will be on my roof?" Long, anonymous subcontractor chains dilute responsibility – when something goes wrong, everyone points at someone else.
4. Knowledge of local procedures. In the city of Zurich, the grid connection is handled by ewz, in the rest of the canton mostly by EKZ; on top of that come municipal notification procedures and separate rules in core zones (details). A company that goes through these procedures regularly saves you weeks.
5. Advice that can also advise against. A good first meeting asks about your consumption and your plans – and sometimes says "that won't pay off for you" or "wait with the battery". Anyone who sells everything that is ordered is not advising.
6. Professional credentials. An electrical installation or connection authorisation is mandatory; labels such as Swissolar's "Solarprofi" are a good additional signal – what they mean (and what they don't): Swissolar Profi & labels. ecoEn is registered with ESTI with an installation authorisation under Art. 14 NIV for photovoltaic systems (No. SOB-284349-1) – verifiable in the public ESTI register.
7. Reachable after installation. Is there a fault service? How are warranty cases handled? A company with its office and team in the region has a structural advantage here over providers who travel in for every project.
The warning signs
The opposite list is just as important. Beware of:
- Doorstep selling and cold calling with "your roof has been selected" rhetoric
- Discounts with an expiry date ("only if you sign this week") – a serious calculation does not expire on Friday
- High advance payments before the material is delivered
- Fantasy yield promises and exact payback guarantees – ranges with assumptions are what's serious
- No Swiss legal form/address when it comes to warranty and liability for defects
The full list of sins: Red flags in solar quotes.
Regional or national – does it matter?
Large national providers can buy cheaply and present themselves professionally; that is legitimate. The structural difference shows at two moments: during planning (does the planner know the municipality, the utility, the roofscape in the neighbourhood?) and after years in operation (does someone come round when there's a fault – or does a ticket odyssey begin?). Our honest assessment of both models: General contractor vs. separate trades and Foreign providers in Switzerland.
Questions for the first meeting
Take this list with you – the answers quickly sort the field:
1. Who plans, who installs, who is liable? 2. Two reference systems near me? 3. What does your quote not include? 4. How does registration with ewz/EKZ and the municipality work – and who does it? 5. What does a service visit cost me in year three? 6. What reserves are you planning for a wallbox or heat pump?
More context on each question: The consultation.
A pattern we see again and again in the region: systems that are technically fine – but nobody ever set up or explained the monitoring to the owner. The system runs, the owner just doesn't know whether it runs well or badly. When choosing a company, "induction and documentation" sounds like a footnote; in everyday life it is the difference between a system you understand and a black box on the roof.
Frequently asked questions
How do I find solar companies near me?
Via Swissolar's Solarprofi search, via recommendations from the neighbourhood – you can see systems from the street – and via targeted enquiries to two or three regional companies. Don't collect ten contacts, collect three good ones.
What does a solar system in Zurich cost?
Guideline prices match the Swiss average: depending on size and roof, typically CHF 2,000–2,800 per kWp turnkey (as of: July 2026). The details: Cost guide.
Does the company have to be from my municipality?
No – but it should serve your region regularly. What matters is the combination of references nearby, knowledge of your grid operator and reachable service.
Are review portals reliable?
As one signal among several. Specific reference systems and behaviour in the consultation are more telling – both are harder to stage than stars.
Does the company also handle heat pumps and wallboxes?
Many companies – including us – offer this in combination. The advantage lies less in a package discount than in coordinated planning: electrics, energy management and reserves are sized correctly once instead of being patched up three times.
What happens if the solar company goes bankrupt?
Legally, every contract for work carries a certain default risk – that applies to every industry. Two things protect you: a payment plan without high advance payments before construction starts (see warning signs above) keeps your financial risk small. And product and performance warranties on modules and inverters run directly through the manufacturer, independently of the installation company. A look at the commercial register and the ESTI register (our installation authorisation: SOB-284349-1) also shows how long a company has been active.
Free initial consultation
Get to know us – without obligation.
ecoEn plans and installs solar systems, batteries and heat pumps in Zurich and the surrounding area – with its own team, its own ESTI installation authorisation (Art. 14 NIV), transparent quotes and references you can visit.
Want to calculate yourself first? Solar calculator with official roof data →
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Photovoltaics Switzerland – installation by a specialist company →
Swissolar member and Solarprofi · ESTI installation authorisation (Art. 14 NIV) · in Zurich since 2017 · over 150 systems completed · a personal answer from the specialist company, no call centre
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Der komplette KaufratgeberSources: Swissolar (Solarprofi directory), ESTI (installation authorisations).
Last updated: 9 July 2026 · Author: ecoEn editorial team
