Tool · Solar
Solar & Smart Energy Pre-Planning
Enter your appliances. Get the system size, the roof area to keep shadow-free, and the conduits and earthing to build in now.
Recommended solar system
10 kW
18 panels × 580 W = 10.44 kWp · hybrid/on-grid inverter 10 kW (3-phase) · ≈ 1,175 units/month
Daily use
26.8 kWh
Peak load
4.9 kW
Needed
7.1 kW
Shadow-free roof area
897 sq ft
Tilted array on a flat RCC roof (rows spaced to avoid self-shading). Flush-mounted on a sloped roof: 573 sq ft.
Battery backup
Grid-tied with net metering (no battery). Enter backup hours to size a battery for essential loads.
Embed before plastering: conduits, cables & earthing
- DC cable (roof → inverter), per string
- 4 mm² PV1-F (UV, double-insulated) · 0.6 % drop
- DC conduits
- 2 × 1 in (25 mm) heavy-gauge PVC (≈ 2 strings + 1 spare)
- AC cable (inverter → DB)
- 4 mm² Cu · 15 A 3Φ · 1 in (25 mm)
- Main DB disconnect (AC MCB)
- 20 A 4P + 30 mA RCD
- DC isolator
- 1000 V DC, ≥ 25 A
- Surge protection
- Type-2 SPD on DC and AC sides
- Earthing rods
- 3 pits: array · AC/inverter · lightning, each 8–10 ft deep
- Earth conductors
- Array 6 mm² · inverter 10 mm² · lightning 16 mm² bare Cu
- Run the conduits in the wall/column chase from the roof to the inverter wall (near the main DB, shaded, ventilated, ≥ 4 ft high). Use sweeping bends and leave a pull-rope.
- Bury earth rods (≥ 10 ft apart) before the compound floor is cast; keep an inspection pit cover on each.
- Roof: build a 1 ft-high RCC plinth with anchor bolts or leave a clear 4 in cut-out for each leg, then waterproof around it.
- Net metering: apply through your DISCO (e.g. PESCO) with the installer; the approved layout may differ.
Assumptions: 5 peak-sun-hours/day (Haripur average), 75 % system efficiency, 1.5-ton inverter AC ≈ 1,100 W average, fridge ≈ 2 kWh/day. This is a pre-planning estimate; the installer's design governs.
Advisory only
This guide is general advice for Haripur / Hazara homeowners. It does not replace a site-specific design by a registered structural engineer (PEC), a soil test, or legal advice from a lawyer. Always follow the approved drawings.