Commercial Solar in Subiaco, WA

Standard 6.6kW residential system: $4,500-$8,000 installed (after federal STC rebate). 10kW system: $7,500-$13,000. 13kW: $9,500-$16,000. Premium tier-1 panels (LG, REC, SunPower) add $1,500-$3,000. Battery (10kWh): $9,000-$18,000 (less Federal Cheaper Home Battery rebate of $4,000-$7,000). Total system with battery typically $13,500-$22,000 fully installed. Always get 3 quotes — prices vary 30-50% between installers for the same system.

The Small-scale Technology Certificate (STC) scheme automatically discounts your solar system at point of sale. Value depends on system size and location zone (Australia divided into 4 zones based on solar resource). For a 6.6kW system: Zone 1 (Darwin, FNQ): ~$3,500. Zone 2 (Brisbane, Perth): ~$3,200. Zone 3 (Sydney, Adelaide): ~$2,800. Zone 4 (Melbourne, Hobart): ~$2,400. The rebate is built into the price installers quote — you never claim it separately. STC values change with carbon market prices and reduce each year (10% reduction in 2030).

Battery economics improved significantly in 2026 with the Federal Cheaper Home Batteries program ($4,000-$7,000 rebate per battery from 1 July 2025). Best for: high evening electricity use, flat or low feed-in tariffs ($0.04-$0.08/kWh in most states), planning long home occupancy (10+ years), EV ownership, virtual power plant participation (extra income). Payback time with rebate: 6-9 years on a $13,000 battery. Top brands 2026: Tesla Powerwall 3, BYD Battery Box, AlphaESS, Sungrow, Sigenergy.

Feed-in tariff is the rate your electricity retailer pays for excess solar energy you export to the grid. Rates have declined dramatically: 2010 $0.40-$0.60/kWh, 2020 $0.10-$0.15/kWh, 2026 typically $0.04-$0.08/kWh (some retailers offer higher with conditions). Rates vary by state and retailer — compare on Energy Made Easy (energymadeeasy.gov.au). Strategy: maximise self-consumption (use power when generating) rather than relying on export. Battery storage shifts excess to evening use instead of low-rate export.

Verify CEC accreditation at solaraccreditation.com.au — required by law for STC rebates. Higher tier: CEC Approved Solar Retailer (industry quality assurance). Look for: 5+ years in business, tier-1 panels (Jinko, Trina, REC, LG), tier-1 inverters (Sungrow, Fronius, SMA, Enphase), product warranties 12+ years, workmanship warranty 5+ years, written quote with components specified, no high-pressure sales. Get 3 quotes and compare apples-for-apples — same panel and inverter brands, same battery if applicable.

From quote to switched-on: typically 4-12 weeks. Process: quote acceptance and deposit (1-2 weeks), site assessment and engineering (1-2 weeks), panel ordering (1-3 weeks for stock items, 4-8 for premium tier-1), installation day (4-8 hours for residential), grid connection paperwork (1-3 weeks). Some states have longer grid connection delays (NSW: 4-8 weeks, VIC: 2-4 weeks). The actual installation day is fast — most of the timeline is paperwork and supply chain. Battery installation adds 1-2 weeks.

First check: inverter display for error codes, app monitoring (most modern systems), and main switchboard for tripped breakers. Common issues: inverter failure (8-12 year typical lifespan, $1,800-$3,500 replacement), single panel failure (rare, covered under product warranty), bird/possum damage to wiring ($300-$800 repair), shading from new growth (tree trim), system disconnected by retailer (check bills). Original installer should provide workmanship warranty support. If they're out of business, any CEC-accredited installer can service the system.