- Reaction score
- 516
Using your figures:
100W x 10Hrs = 1000Wh = 1kWh
4.16 kWh @ 0.13p = 0.5408 £ (you are a factor of 10 out)
So you'll cave 54p each cycle
so so break even you need to do that FULL cycle 3700 times.
Now in practice there are a very large number of days when you won't have 5.2kWh (5200Wh) 'spare' that you would have exported. Let me be generous and say that on a 4kWp system you could do that for 6 months of the year (some days you'll get zero, some days you may still be exporting) so on an average year you'll achieve 185 fce's (Full cycle equivalents)
That gives you a 20 year pay back assuming zero maintenance costs, and no additional costs over the £2000.
100W x 10Hrs = 1000Wh = 1kWh
4.16 kWh @ 0.13p = 0.5408 £ (you are a factor of 10 out)
So you'll cave 54p each cycle
so so break even you need to do that FULL cycle 3700 times.
Now in practice there are a very large number of days when you won't have 5.2kWh (5200Wh) 'spare' that you would have exported. Let me be generous and say that on a 4kWp system you could do that for 6 months of the year (some days you'll get zero, some days you may still be exporting) so on an average year you'll achieve 185 fce's (Full cycle equivalents)
That gives you a 20 year pay back assuming zero maintenance costs, and no additional costs over the £2000.