Residential Solar FAQ

Roof suitability depends on available space, roof condition, access and shading. Because Singapore is close to the equator, suitable north-, south-, east- and west-facing roof sections can all contribute effectively depending on roof pitch, shading and surrounding obstructions. A site assessment helps establish a suitable layout and whether further professional checks are needed.

Required roof space depends on the exact panel dimensions, access paths, setbacks and mounting layout. A system around 10 kWp may use roughly 19 panels rated at 540W, but panel count alone does not establish a suitable roof layout. We assess usable roof area before recommending a system.

Physical roof mounting structure installation, panel fitting, and electrical wiring typically take 3 to 4 days on site.

Physical roof and electrical installation typically takes 3 to 4 days on site. The full process—including SP Group grid connection approval and LEW submission—takes approximately 4 to 6 weeks from project execution.

Surplus solar electricity may be exported to the grid under an approved arrangement. Eligible non-contestable households buying from SP Group under Simplified Credit Treatment (SCT) receive the regulated tariff less grid charges, reviewed with tariff changes. Customers buying from electricity retailers may use ECIS, where export payments depend on prevailing half-hourly wholesale electricity prices rather than a fixed SP/SCT rate.

Yes. Solar panels generate power from ambient solar irradiance, not just direct sunlight. While peak output occurs during clear, sunny afternoons, modern N-Type monocrystalline panels continue generating electricity at reduced capacity during overcast or rainy Singapore weather.

For safety reasons, standard grid-tied solar inverters automatically shut down during a public power grid outage (islanding protection). This prevents hazardous back-feeding of electricity into grid power lines while technicians perform repairs.

Panels have no moving parts, but the complete installation needs performance monitoring and periodic inspection. Rain does not remove every type of dirt. Inspection and cleaning frequency depend on site conditions and the maintenance coverage in your agreement; rooftop work should be carried out by suitably equipped personnel.

Actual electricity bill savings depend on several key factors: available unshaded roof space, roof orientation, household daytime electricity consumption habits, total installed system size, prevailing electricity tariffs, and applicable grid export credit rates.

Product and panel performance warranties are manufacturer-specific. Workmanship covers the installation items expressly listed in your agreement, while maintenance specifies agreed inspections or cleaning. Duration, exclusions and the claims process are provided with your proposed system; a performance warranty is not a guarantee of electricity-bill savings.

We select mounting methods appropriate to the roof type and take care over waterproof sealing. Existing roof condition and the proposed fixing method should be assessed before installation; any required repairs or limitations will be discussed with you.

Interconnection with the national grid requires formal electrical single-line diagram endorsement by a Licensed Electrical Worker (LEW) and grid connection clearance from SP PowerGrid. Vonx Solar manages all technical applications and administrative submissions on your behalf.

While daytime solar generation can significantly lower or even offset your daytime energy usage, night-time electricity consumption is supplied from the grid. Export credits generated during daytime help offset grid charges, but fixed utility service fees or evening consumption may remain.

You can request a no-obligation solar assessment by filling out our online Enquiry Form or contacting us via WhatsApp (+65 9187 9573). Our engineering team will evaluate your property address and roof profile to prepare a customized feasibility report.