.jpeg)
Every homeowner who has gone through the process of finding the right solar installer will tell you the same thing: the quality of the questions you ask determines the quality of the outcome you get. This guide walks you through the 10 most important questions to ask any solar installer before signing anything, plus 5 bonus questions that experienced buyers ask once they have already evaluated the basics.
Why the right questions matter
Solar installations are long-term investments. A correctly specified system will generate clean energy for 25 years or more. A poorly specified one will leave you with sub-optimal output, unexpected costs, and limited options if something goes wrong. The right installer will welcome these questions because they signal a serious, informed buyer.
The core 10 questions
1. Are you a licensed electrical worker in Singapore?
All solar installations in Singapore require an EMA-licensed electrical worker to certify the work. Ask for their licence number and verify it directly with the Energy Market Authority. Any reputable installer will have this information on hand. If they hesitate, that is a significant warning sign.
2. Are you accredited by the Singapore Solar Energy Research Institute (SERIS) or BCA GreenMark?
Industry accreditations signal that the company has met independently verified standards. SERIS endorsement or BCA GreenMark certification for solar products indicates a level of quality assurance that self-reported credentials cannot provide. Ask specifically which accreditations apply to the installation work, not just the panels themselves.
3. What warranties are you offering, and who backs them?
This is one of the most important questions you can ask. A complete solar system has at least three separate warranties: panel performance (typically 25 years for Tier 1 manufacturers), product warranty (covers physical defects, usually 10–25 years depending on the brand), and workmanship warranty (covers the installation itself, should be a minimum of 5 years, though 10 is better). Ask to see the actual warranty documents, not just a summary in a brochure. For workmanship specifically, ask what happens if the installer closes operations during the warranty period.
4. Which panels and inverter brand will you be using, and why?
The specific components matter. Tier 1 panels from manufacturers with independently audited production processes outperform cheaper alternatives in long-term degradation rates. The inverter is the most complex electronic component in the system and is statistically the most likely to require servicing. Ask the installer why they selected the specific brands they are recommending and whether alternatives were considered.
5. How do you assess my roof before recommending a system size?
A competent installer will conduct a site assessment that includes roof orientation and tilt angle, shading analysis across different times of day and seasons, roof load-bearing capacity (particularly important for older HDB blocks), and structural integrity for the mounting system. Be wary of any installer who quotes a system size without visiting your property or conducting a digital survey using satellite imagery tools.
6. Will this installation require BCA approval, and will you manage that process?
Certain installations in Singapore, particularly on landed properties with roof modifications, may require approval from the Building and Construction Authority. For HDB flats, there are specific conditions around panel placement and structural assessments. Ask clearly who is responsible for obtaining the necessary approvals and whether that cost is included in the quote.
7. How will you handle the SP Group Net Energy Metering application?
Connecting your solar system to the grid requires an approved application to SP Group. This involves a technical review, meter replacement, and approval process that typically takes several weeks. Your installer should manage this process on your behalf. Ask them how long this typically takes for their customers and whether they will keep you updated throughout.
8. What is included in your post-installation support?
Solar panels require minimal maintenance, but inverters sometimes need attention and monitoring systems occasionally need resetting. Ask specifically what the installer will do in year two or year five if something stops performing correctly. Find out whether their post-installation support is reactive (you call them when something breaks) or proactive (they monitor your system and contact you).
9. Can you provide references from previous customers in Singapore?
Verifiable references from past customers are a significant quality signal. Ask for references from installations completed in the last 12 to 24 months, and contact those customers directly. Ask them specifically about the communication during the project, the accuracy of the initial energy savings projections, and how any issues were handled after installation.
10. What is your company’s track record in Singapore?
The solar industry attracts new entrants regularly, and some companies that were active three years ago are no longer trading. Ask how many installations the company has completed in Singapore specifically, how long they have been operating, and whether they have a physical office in Singapore. A company with a genuine operational history in the local market is far better positioned to honour long-term warranties and service commitments.
5 bonus questions for serious buyers
Bonus 1: What is the actual system size you are recommending, and how did you calculate it?
A correctly sized system is matched to your actual electricity consumption, not just your available roof space. Ask the installer to walk you through the calculation. They should be referencing your last 12 months of electricity bills, your daily usage patterns, and the orientation and shading profile of your roof.
Bonus 2: What is the expected annual energy yield for my specific installation?
Ask for a projected annual energy yield in kilowatt-hours (kWh), not just a monthly savings figure. The yield should be modelled using solar irradiance data for Singapore (approximately 1,580 kWh per kWp per year under standard conditions, with variation based on roof profile). If the installer cannot provide a projected yield figure with assumptions clearly stated, that is a gap in their technical capability.
Bonus 3: What is your installation process, and how long will it take?
A typical residential solar installation in Singapore takes one to two days of physical installation work, but the total project timeline from contract to grid connection is usually four to eight weeks once approvals and metering are factored in. Ask for a project timeline with clear milestones and understand what the dependencies are at each stage.
Bonus 4: Do you offer system monitoring, and what does it show?
Modern solar systems include real-time monitoring, typically accessible via a mobile app. Ask what data is available, how granular it is, and whether the installer has access to your system performance data. Panel-level monitoring, where each panel’s output can be viewed independently, is significantly more useful than inverter-level monitoring for diagnosing performance issues early.
Bonus 5: What happens at the end of the system’s life?
Solar panels have a working life of 25 to 30 years. Ask the installer what the options are at end of life, including panel recycling and system decommissioning. Singapore has developing frameworks around solar panel recycling, and a forward-thinking installer should be able to speak to this topic clearly.
The right installer will treat these questions as a sign of a serious buyer, not an obstacle. If any company is unwilling to answer directly and in writing, that itself is useful information about how they will handle your project.
Try Sunollo: www.sunollo.com
Once you have your shortlist of installers, compare solar plans and pricing to understand exactly what each package includes before your first consultation.
.jpg)
