Mr Pool of Kenilworth installs a 2.40 kW system comprises of 10 E19 240w panels. Costing £5010.00 this system would produce 2,060 kWh/year. We assume half the electricity is used in the building, half exported to the grid. He would earn; (2060X £0.149) (Generated Electricity) + (2,060 / 2 X £0.0464) (Exported Electricity) = £306.92+ £47.79= £354.71 he would save (save buying half of the electricity); (2,060 / 2 X £0.13) = £129.79Total £484.50/year. A return on investment of 9.5%! The system would pay for itself in year 9 and earn a total profit of £13,477* over 20 years!!
Mr Conlon of Redditch has a larger roof and installs a 3.92Kw Solar PV System costing around £8,100. The system would produce 3,463kWh/year. We assume half the electricity is used in the building, half exported to the grid. He would earn; (3463X £0.149) + (3463/ 2 X £0.0464) = £516.01+ £80.34= £596.35 He would save (save buying half of the electricity); (3463/ 2 X £0.13) = £225.09 Total £821.44a year. A return on investment of 10%! The system would pay for itself in year9 and earn a total profit of £21,586.79* over 20 years!! * The profit figure does not take into account the time value of money. This underlines the fact that there is clearly a benefit in installing the largest possible system on your roof. For more information please visit the Department of Energy & Climate Change website. If you would like to find out how much your roof could earn you please request a consultation.