rtcosic
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- 2,615
- Location
- Warwickshire
Finally sorted out the data for the first full year of operation and reconciled with supplier bills.
1 June 22 to 31 May 23:
Gross PV Generation 5280 kWh
Self Consumption 1938 kWh
Import 2871 kWh
Gross Consumption 4810kWh
Export 3342kWh
Import avoidance £345
Export revenue £137
Total return £483
Total investment £7070.71
My system has 5.46kW nominal array, but limited by a 3.6kW inverter.
Return 6.8% or 15 years which given achievable interest rates when the investment decision was made is reasonable.
It will be 'interesting' to see what the figures look like when my fix expires in March 2024. I currently pay 17.82 p/kWh import and receive 4.1 p/kWh export
For a possible battery I looked at the balance each month. The maximum it can save is the lesser of the export or import at the difference between import and export tariff. On that fairly simplistic basis the potential saving over the same period is only £183.
So unless there is around £250 or more per year to gain from arbitraging the high/low tariff periods as well, I still can't see a battery paying its way for us. Unless a monster one is very cheap and I can save June, July and August's surplus to draw down from November to March!
1 June 22 to 31 May 23:
Gross PV Generation 5280 kWh
Self Consumption 1938 kWh
Import 2871 kWh
Gross Consumption 4810kWh
Export 3342kWh
Import avoidance £345
Export revenue £137
Total return £483
Total investment £7070.71
My system has 5.46kW nominal array, but limited by a 3.6kW inverter.
Return 6.8% or 15 years which given achievable interest rates when the investment decision was made is reasonable.
It will be 'interesting' to see what the figures look like when my fix expires in March 2024. I currently pay 17.82 p/kWh import and receive 4.1 p/kWh export
For a possible battery I looked at the balance each month. The maximum it can save is the lesser of the export or import at the difference between import and export tariff. On that fairly simplistic basis the potential saving over the same period is only £183.
So unless there is around £250 or more per year to gain from arbitraging the high/low tariff periods as well, I still can't see a battery paying its way for us. Unless a monster one is very cheap and I can save June, July and August's surplus to draw down from November to March!