If you're a homeowner thinking about solar, this is the guide we wish existed when we started fielding consultation requests in 2020. It walks through every decision you'll face, in order, with the specifics that actually matter.
Nothing about "clean energy future" or "join the movement." Just the practical stuff.
Is your home a good candidate?
Not every home is. The four filters to run, in order:
1. Roof orientation
Ideal: south-facing (northern hemisphere) or north-facing (southern hemisphere), at a pitch close to your latitude. East- or west-facing roofs work but lose 10–20% of annual yield. Opposite-facing roofs (north in northern hemisphere) can lose 30%+ — often enough to kill the economics.
2. Shading
Walk around your property at midday. If tall trees, neighbouring buildings, or terrain shade your roof for more than an hour around solar noon, flag it for detailed shading analysis. Shading in the early morning or late afternoon matters less.
3. Roof condition
Solar systems are designed for 25+ years. If your roof has less than 15 years of life remaining, replace it first. Installing solar on a roof that needs replacing in year 5 costs you the de-install / re-install fee — effectively doubling installation cost.
4. Roof structure
Modern solar adds 15–20 kg per square metre. Most modern homes handle this fine, but older structures or unusual framing need to be assessed. A competent supplier will do this during feasibility.
A supplier who tells you solar is right for every home regardless of orientation, shading, or roof age isn't giving you advice — they're making a sale. Good suppliers will tell you to wait, or to fix the roof first, when that's the correct answer.
Sizing a home system
The right size isn't "maximum panels that fit on the roof." It's the size that matches your consumption pattern and your utility's export rules.
Start with your electricity bills
Pull 12 months of bills. Note the total annual consumption in kWh. That's the ceiling for how much solar can meaningfully offset.
Match to your net-metering regime
- One-for-one net-metering: size up to match your annual consumption. Any extra is wasted or credited at near-zero.
- Net-billing or self-consumption: size for what you actually use during daylight hours — typically 40–70% of annual consumption for most households.
Typical home sizing
- Small home, moderate consumption: 3–5 kWp (8–12 panels)
- Standard family home: 5–8 kWp (12–20 panels)
- Large home with pool, EV, AC throughout: 8–15 kWp (20–38 panels)
Budget and payback
Residential solar pricing varies across Asian markets, but the economic structure is consistent:
- Hardware (panels, inverter, mounting, BOS): roughly 55–65% of total.
- Design, permitting, interconnection: roughly 10–15%.
- Installation labour: roughly 20–30%.
- Optional: batteries add significantly — often 50–100% of the base system cost.
Typical payback for a well-sized residential system in Asian markets: 5–8 years on cash purchase. Over the 25-year system life, you're typically looking at total returns of 3–4× the original investment after accounting for one inverter replacement.
The process, step by step
- Initial consultation (45 minutes). Review your bills and goals. Identify obvious red flags (bad orientation, heavy shading, old roof).
- Site survey. On-site visit to measure roof, check electrical panel, confirm structure.
- Yield modelling and design. Specific production estimate based on your roof, your climate, and your shading profile. Full bill of materials.
- Proposal and contract. Written proposal with yield model, BOM, warranty schedule, and payment terms.
- Utility application. Grid connection paperwork. Timeline varies 1–8 weeks depending on utility.
- Installation. Coordinated with our installation partner. Typically 1–2 days on a home site.
- Commissioning. Final testing, utility inspection, connection to grid.
- Ongoing. Monitoring app shows production from day one. Service contact is direct — not a call centre.
What to watch for
Common homeowner pitfalls:
- Undersized inverter. Some quotes pair aggressive panel counts with inverters that can't handle peak output. You lose production in midday. Ask about inverter capacity vs array size.
- Cheap mounting hardware. Saves a few hundred dollars, costs you a leaking roof in year 7. Tier-1 mounting systems are non-negotiable.
- Roof penetrations without proper flashing. The place where water ingress starts. Check that the installer uses manufacturer-approved flashing kits appropriate to your roof type.
- Warranty terms in fine print. Read the warranty section before signing. If the workmanship warranty is 1 year while the hardware warranties are 25, the installer doesn't stand behind their own work.
- No monitoring. Without production monitoring, you won't know for years that your system is underperforming. Insist on monitoring, and check it monthly for the first year.
After installation
A solar system is not install-and-forget. Low maintenance, not zero maintenance.
- Year 1: Check monitoring monthly. Confirm the system is producing close to the modelled output. Flag any underperformance immediately while workmanship warranty is fresh.
- Years 2–10: Visual check once a year for obvious issues (loose components, damage, bird nests under panels). Clean panels only if your climate demands it.
- Year 10–12: Expect inverter replacement around now. Budget for it from day one.
- Years 13–25+: Panels continue producing with ~0.5% per year degradation. By year 25 you're typically at 85% of original output. Many systems keep producing well beyond 25 years.