Savings from your 3kW solar power system
Yearly Average = 14 Units
Assuming:
10kWh is consumed during daytime and the balance 4kWh is exported to grid.
7 cents is paid for every unit of energy fed back to the grid.
Cost of each unit of energy from utility supplier24 cents.
Every day the house hold will earn:
Electricity Savings:
10 kWh x 24 cents = $2.40/day
Credit earned from feed-in:
4kWh x 7 cents = $0.28/day
Total: $2.68/day
Savings from your 5kW solar power system
Yearly Average = 24 Units
Assuming:
18kWh is consumed during daytime and the balance 6kWh is exported to grid.
7 cents is paid for every unit of energy fed back to the grid.
Cost of each unit of energy from utility supplier24 cents
Every day the house hold will earn:
Electricity Savings:
18 kWh x 24 cents = $4.20/day.
Credit earned from feed-in:
6kWh x 7 cents = $0.42/day
Total: $4.62/day
The savings can be maximized by you using of energy intensive devices like the pool pump, washing machine, dryer, dish washer etc to the day time when the solar system is running and you have excess solar energy.
PS: All these savings are approximate. Exact amounts will depend on the power usage pattern in a house against the solar system size.