Residential

A 4.0 kWp Solar PV system on a south facing roof (or ground mounted), in Northern Ireland, will produce approximately 3,380 kilowatt hours of electricity per annum. If 50% of the energy produced was used on site the financial returns would be as follows:

System Size

4.0 kWp

Quantity of modules

16 modules (roof area required 28m²)

Annual electricity yield

3, 380 kWh/annum

Annual ROC payment

£573.24

Electricity saved (assuming 0.17p/kWh)

£287.30

Electricity exported to the grid

£100.55

Total annual benefit - income and savings

£961.09

Payback period

6.2 years (ROI 11%)

 

A 6.5 kWp Solar PV system on a south facing roof (or ground mounted), in Northern Ireland, will produce approximately 5,490 kilowatt hours of electricity per annum. If 50% of the energy produced was used on site the financial returns would be as follows:

System Size

6.5 kWp

Quantity of modules

26 modules (roof area required 45m²)

Annual electricity yield

5,490 kWh/annum

Annual ROC payment

£931.10

Electricity saved (assuming 0/17p/kWh)

£466.65

Electricity exported to the grid

£163.32

Total annual benefit - income and savings

£1,561.07

Payback period 

5.7 years (ROI 12.5%)

 

These figures do not allow for the expected increase in electricity prices and value of the ROC over the period which may decrease the payback time and increase the return on investment.