How to Choose a Renewable Energy Installation Company – Complete Guide

Why is choosing the right company crucial?

The renewable energy market for individual customers in Poland, despite entering a stabilization phase after years of intensive development, still offers enormous opportunities for prosumers considering investment in photovoltaic installations, heat pumps, or energy storage systems. By the end of June 2025, the number of all micro-installations connected to the DSO distribution network reached nearly 1.586 million, with their capacity exceeding 13.1 GW (data source: Polish Society for Electricity Transmission and Distribution).

However, for the average individual customer, market statistics are not the most important thing, but rather the practical question: how to choose an installation company that will carry out the investment professionally, on time, and honestly? Rising energy prices and availability of support programs mean that more and more homeowners are considering RES installations, but at the same time, the market is filling with companies of varying reputation and competence.

Most common problems homeowners face with contractors

Unfortunately, along with the development of the industry, unreliable entities have also appeared. Consumers report problems with faulty installations, lack of service, and even companies disappearing right after installation completion. Unfortunately, the renewable energy sector is among those where consumer rights violations occur most frequently.

The most common problems include:

• Installations executed inconsistently with the project or safety standards
• Use of lower quality components than ordered
• Lack of adequate service support after work completion
• Problems with launching billing with the grid operator
• Incorrect documentation submitted to authorities

What you can gain and lose with a poor choice

Choosing the right installation company is a decision that will affect the functioning and profitability of your installation for the next 20-25 years. A poorly chosen company can mean not only financial losses, but also safety problems, warranty loss, or legal troubles with authorities.

The right choice guarantees an installation that will generate savings according to predictions, operate trouble-free, and bring satisfaction from well-invested money.

Get to know the RES installation company market in Poland

Who operates in the market – from sole proprietorships to corporations

The Polish RES installation market is characterized by enormous diversity of contractors. Both small installation companies operate here, where the owner employs about 2-3 people who independently perform installations, as well as large corporations with extensive teams, where various departments function: sales, marketing, service, etc. Each model has its advantages and disadvantages.

Small companies often offer more personalized service and competitive prices, but may have limited operational range and smaller financial capabilities in case of problems.

Large companies ensure stability and a wide range of services, but sometimes at the cost of flexibility and individual approach to the customer. Larger companies usually delegate installations to external installers. When choosing such a company, I encourage you to ask about the qualifications and experience of the people who will perform the installation in your home. But more on that later.

Typical business models of contractors

In the market, you’ll encounter different company operating models:

• Full service – from design through installation to service + subsidy handling for customers
• Specialist installers – installation only, you prepare documentation (e.g., for subsidies) yourself
• Franchises – local companies operating under a larger network brand

Where to look for installation companies

The best sources are:

• Recommendations from acquaintances with RES installations
• Specialized industry portals with verified companies
• Trade fairs and industry events
• Equipment manufacturer websites with lists of authorized installers

If a company contacts you solely through telemarketing or door-to-door visits – verify it according to our recommended checklist, which I presented in the second part of the article.

Basic checks – first verification steps

Documents you must check:

CEIDG or KRS registration

Every company must be registered. For sole proprietorship, check the entry in the Central Registration and Information on Business Activity (CEIDG), and for companies – in the National Court Register (KRS). Pay attention to:

• Date of business commencement
• Whether the activity has not been suspended
• Whether the business scope includes electrical work and RES

Required permissions and installer certificates

Installers must possess:

• SEP electrical permits up to 1 kV, group G1 – for electrical equipment, installations and networks
• SEP permits group G2 – for heating equipment
• Specific manufacturer certificates (to maintain warranty)
• Current health and safety training
• Possibly UDT certificate in renewable energy sources (photovoltaics, heat pumps)
• For split-type heat pumps: f-gases and “f-gases for company”

Business liability insurance

The company should have liability insurance of at least 100,000 PLN, and preferably much more. Ask to see the policy.

References and market experience

How to verify a company’s real experience

The mere existence of a company for several years is not enough. Check:

• Number of completed installations (especially similar to yours)
• Whether the company has experience with your roof/building type
• Whether the company has experience installing all RES you plan to install, i.e., photovoltaics, heat pumps, energy storage

Portfolio of implementations – what to pay attention to

Ask for a portfolio with implementations from the last 2-3 years. Pay attention to:

• Quality of aesthetic execution (cable routing, structure mounting)
• Project diversity
• Whether the company can perform installations on different types of roofs

Contact with previous customers

A good company will gladly provide contacts to their customers. Ask previous customers about:

• Implementation timeliness
• Communication quality
• Any problems after startup and the company’s response
• Whether they would recommend this company

Financial credibility assessment – will the company go bankrupt?

Checking financial condition in public databases

Use:

• Business Information Bureau – financial liquidity reports
• National Debt Register – whether the company has arrears
• Court and Commercial Department – whether bankruptcy proceedings are ongoing

Warning signals regarding financial liquidity

Beware of companies that:

• Require full prepayment before starting work
• Have very low prices compared to competition
• Pressure for immediate contract signing
• Operate briefly but realize a very large number of projects

What distinguishes a young company from an unstable one

A young but solid company:

• Has experienced founders from the industry
• Starts operations gradually, building reputation
• Invests in training and certificates
• Has realistic market prices

Product and technology quality – what does the company offer?

Cooperation with manufacturers

Authorized partners vs. importers

Authorized partners offer:

• Full manufacturer warranty
• Access to newest products
• Technical support from manufacturer
• Installer training

Importers may offer more attractive prices, but often at the cost of limited warranty or service problems.

Equipment warranties

Pay attention to warranty length and conditions. Standard warranties are:

• PV panels: 12 years on product, 25 years on efficiency
• Inverters: 5-10 years with extension possibility
• Mounting structures: 10-15 years
• Installation: minimum 2 years

Modernity and efficiency of solutions

A good company should:

• Offer panels with minimum 400W+ power
• Propose inverters with optimizers or micro-inverters in difficult conditions
• Consider possibility of later adding energy storage
• Suggest energy production monitoring systems

Cooperation process – from first contact to installation acceptance

Quotation and technical visit

What a free quote should include

• Analysis of energy bills from the last 12 months
• Roof measurement or building plan analysis
• Optimal installation configuration proposal
• Energy production simulation
• Investment return calculation

Technical visit – key audit elements

Professional audit includes:

• Roof structure condition assessment
• Sunlight analysis (shading consideration)
• Building electrical installation check
• Optimal inverter and meter location determination
• Identification of potential technical problems

Offer and contract – what to watch for

Elements of a reliable commercial offer

A complete offer contains:

• Detailed specification of all components (manufacturer, model, parameters)
• Panel arrangement scheme on the roof
• Expected annual energy production
• Savings calculation
• Payment and implementation schedule

Most important contract clauses

Check if the contract contains:

• Exact description of work scope
• Implementation deadlines with contractual penalties for delays
• Warranty and complaint conditions
• Installation acceptance procedures
• Responsibility for obtaining permits and grid connection

Project implementation – quality control

Professional installation – standards and norms

Pay attention to:

• Proper roof protection against leakage
• Aesthetic cable routing
• Application of appropriate electrical protections
• Placement of informational and warning signs

Installation acceptance – control list

Before acceptance, check:

• Whether all photovoltaic modules are installed according to the project
• Monitoring system operation
• Documentation completeness (warranties, user manuals)

Service and support – what happens after installation?

Warranty and service – differences and rights

Installation warranty is minimum 2 years, but a good company offers:

• Periodic inspections
• Remote system operation monitoring
• Quick response to failures (max 48 hours)
• Transparent cost policy after warranty period

Technical help availability

Check if the company offers:

• Technical helpline during business hours
• Remote problem diagnosis
• Service network in your region
• Replacement during key personnel vacations

Subsidies and financing – practical help

Help in obtaining grants and tax reliefs

A professional company should:

• Inform about available support programs
• Help fill out applications
• Provide required documents and certificates
• Inform about tax reliefs

Installation financing possibilities

Check if the company cooperates with:

• Banks offering RES credits
• Leasing companies

Grid operator settlements – company support

A good company will help with:

• Submitting connection application
• Prosumer billing startup process
• Bidirectional meter configuration
• First settlement with operator

Red flags – alarm signals to avoid

Dishonest installation company practices

Avoid companies that:

• Offer prices significantly lower than market (difference above 20-30%)
• Require full prepayment before starting work
• Have no permanent headquarters or operate only mobile
• Cannot present references from previous customers
• Do not possess appropriate permits and certificates

Most common RES market scams

Warnings against:

• Promises of “free energy” without cost explanation
• Companies offering installations “on trial”
• Door-to-door sales with time pressure
• Hiding real additional costs
• Unrealistic investment return forecasts

Offers “too good to be true”

Especially check offers that:

• Promise investment return in less than 5 years
• Guarantee specific savings without energy consumption analysis
• Offer installations significantly below component costs
• Contain hidden costs discovered only in the contract

Your checklist – step-by-step guide

20 questions you must ask the installation company

1. How long has the company been operating in the RES market?
2. How many installations similar to mine have you completed?
3. What permits and certificates do you possess?
4. Can I contact previous customers?
5. What equipment brands do you recommend and why?
6. How does the warranty and complaint process work?
7. Do you offer after-sales service?
8. How long does project implementation take?
9. Who will perform the installation?
10. What documents will I receive after work completion?
11. Do you help with official formalities?
12. What is the actual production of similar installations?
13. Do you offer financing or help with grants?
14. What happens if the company stops operating?
15. How often should the installation be serviced?
16. Does the installation require any operation from my side?
17. How to monitor system operation?
18. What to do in case of failure?
19. Can I expand the installation in the future?
20. What are the additional costs beyond installation price?

Documents to check before signing contract

• CEIDG or KRS entry
• Liability insurance policy
• Installer certificates and permits
• Portfolio with references
• Detailed technical specification
• Warranty conditions
• Payment schedule

Your action plan

Most important contractor selection rules

• Don’t be guided only by price – too low price often means quality savings
• Check references – talk to previous customers
• Verify documents – permits, insurance, certificates
• Choose experienced ones – min. 3 years in RES market
• Read contracts – all conditions should be clearly defined
• Remain cautious – avoid time pressure and 100% prepayments

First steps after reading the article

1. Prepare analysis of your energy bills from the last 12 months
2. Determine investment budget
3. Create a list of 3-5 companies to check
4. Request technical visits and offers
5. Use the checklist when choosing
6. Don’t sign the contract immediately – think over the decision for several days. Remember, you don’t have to decide on purchase right away!

Remember: a well-chosen installation company is a guarantee of successful investment that will please you for the next two decades.

Useful contacts and information sources

Company and certificate databases

• SEP (Association of Polish Electricians) – electrical permits database
• UDT – list of accredited RES installers – https://www.udt.gov.pl/wykazy/rejestr-certyfikowanych-instalatorow-oze.html?INST-OZE

Control institutions and consumer organizations

• UOKiK – in case of practices violating consumer rights
• URE (Energy Regulatory Office) – connection and billing issues

In summary, choosing an installation company, whether for photovoltaic installation, heat pumps, or energy storage is an important undertaking worth spending time on to properly verify its reliability and quality. I hope that the checklist presented in the article will help you, dear reader, in properly checking the company that will implement your investment.

Follow us, as we are soon launching a campaign aimed at educating investors about criteria for choosing professional installation companies in the RES industry and raising quality standards in the industry.

Download the free Checklist – “Choosing a RES Installer” in PDF format – https://bit.ly/417Zky3