Now that we have had our solar and battery system for 2 years, I have calculated the energy costs for the 6 years we have been living at our present home as it may assist others.
SOLAR SYSTEM PERFORMANCE
ANNUAL SYSTEM OUTPUT
SYSTEM DETAILS
- 6.6 Kw. 22 x Seraphim 300 watt panels. 11 facing East. 11 facing West.
- Sungrow SH5K-20 inverter.
- Sungrow backup box.
- LD RESU10 battery.
SYSTEM PRICE AND PAYBACK
Total installed price $15,733
Deposit $2,733
Qld Government grant $3,000
Qld Government 10 year loan $10,000
The system has slashed our electricity costs from an annual average of $1,979.21 between 2015 and 2018 to an average of $436.78 in 2019 and 2020, a saving of $1,542.43 less the $1,000 annual repayment to the Qld Government, thus a nett saving of $542.43 per annum.
However, the battery does not stack up financially.
If one uses the average annual amount of the solar output used to charge the battery of 1,813.50kwh and multiply it by the 16 cents difference between Tariff 11 and the F.I T., it is a saving of just $290.16 per annum.
The battery is really only viable to keep power on when the mains power goes down.
