The False Economy of Cheap Solar

Are cheap solar panels a false economy?

We modelled 25-year returns for budget vs premium solar panels: BUDGET SYSTEM (£5,500): Panels: unknown brand, 17% efficiency, 380W. Degradation: 0.7%/yr. Warranty: 10yr product, 25yr at 80%. Inverter: basic string, 10yr warranty. 25yr generation: 78,500 kWh. 25yr savings: £14,200. PREMIUM SYSTEM (£8,500): Panels: REC/SunPower, 22% efficiency, 430W. Degradation: 0.25%/yr. Warranty: 25yr product, 25yr at 92%. Inverter: hybrid, 12yr warranty. 25yr generation: 91,800 kWh. 25yr savings: £17,800. DIFFERENCE: £3,000 more upfront → £3,600 more savings over 25 years. NET BENEFIT OF PREMIUM: +£600 profit AND better warranty, better monitoring, battery-ready inverter. MID-RANGE SYSTEM (£7,000): The sweet spot. LONGi/JA Solar panels (21%, 400W, 0.4% degradation). 25yr generation: 86,200 kWh. 25yr savings: £16,400. Best ROI per pound invested. Sources: Manufacturer datasheets, PVGIS generation data (re.jrc.ec.europa.eu), Ofgem pricing (ofgem.gov.uk).