On-grid Rooftop Solar

How an on-grid system works

Panels produce DC power, the on-grid inverter turns it into AC and feeds the building's switchboard. The building uses solar power first and draws the rest from the grid as usual. There is no battery, so when the grid goes down the inverter stops by itself (anti-islanding) to protect line workers who may be repairing the network. If you need power during outages, look at hybrid solar with battery.

Sized to your daytime load

We start from twelve months of electricity bills and, where possible, one to two weeks of measured load. What matters is the daytime base load (09:00–15:00), not the monthly total. A system larger than the daytime load overproduces, and with zero-export set, that surplus is simply curtailed.

An example: an office that steadily draws about 8 kW during the day suits a system of roughly 8–10 kWp. With about 4.5–5.5 kWh/m²/day of sun across Laos and Thailand, a 10 kWp system makes roughly 35–45 kWh on a good day and less in the rainy season. That is an estimate, not a guarantee.

Zero-export and export limiting

Many buildings do not want, or are not able, to push power back into the grid. We install a smart meter or CT on the incoming supply; the inverter reads it and throttles its own output so nothing flows out. We coordinate the grid connection with the local power utility for you.

What makes a system last 25 years

• Tier 1 panels and an inverter named by brand and model on the quote
• String sizing checked against Voc on the coldest morning and voltage on a 70°C roof
• DC isolators, SPDs on both DC and AC sides, and measured earthing
• MC4 connectors of the same make on both halves of every joint, never mixed brands
• A structural check of the roof and waterproofing at every penetration

Send us photos of your roof and your last three electricity bills on WhatsApp. We will tell you what system size makes sense and what we need to check on the site visit.