The embodied energy of a PV installation has a longer payback period than that of a wind turbine. This is due to the relative immaturity of the technology. The payback period is expected to be around 3 years. With this period taken into consideration, the expected saving of one 3960W roof unit over a 20 year period is projected to be 41.2tonnes. If utilisation of all possible 440 sites took place, then a total saving of around 18147tonnes of CO2 could be made. With a capital cost of around £21000 for the system this equates to around £509 per tonne of CO2 saved. With the economic aspects of the loan and FIT considered, a potential gain of around £121 could be made with every tonne of CO2 saved.
Assessment for One Scheme |
||
Total CO2 Saved |
41.24 |
tonnes |
Capital Cost per tonne |
509.16 |
£/tonne |
Income with FIT |
121.13 |
£/tonne saved |
440 Schemes | ||
Total CO2 Saved |
18147.41 |
tonnes |
Table 1: Amount of CO2 saved for an individual scheme and the total schemes