Carolyn Lee
Kiama
Battery storage leads to 99.9% self-sufficiency – even with an electric vehicle!
Carolyn Lee is one of the Directors of The Energy Experts. Within 4 days of moving into her new home in Kiama in June 2020, there was a high-performance 6.5kW solar power system installed on her roof. When she and her partner decided to get an electric vehicle (EV) in June 2023, they expanded their solar power system to 10.2kW and added battery, together with a smart EV charger.
| Previous electricity bill | Current electricity usage from grid | Current Bill Credit | |
|---|---|---|---|
| Average consumption: | Solar installed at purchase | 0.61kWh/day | $202 |
| Average cost: | Solar installed at purchase | $0 |
| Solar power system installed: |
|---|
| 10.2kW system using 28 x LG panels, 28 x SolarEdge optimisers, 10kW SolarEdge inverter, a SolarEdge 10kWh Home Battery with Back-Up Interface for blackout protection, a SolarEdge Smart Hot Water Controller and a SolarEdge Smart EV Charger. |
Caro was determined to get a system that would give her and her partner maximum future-proofing functionality, as they weren’t planning on selling their property anytime soon and they knew they wanted to get an electric vehicle within 1 or 2 years. She wanted a solution that would allow for future system expansion if needed.
Their solar array, which faces east and west, generates peak power from 8am-4pm. Caro and her partner work from home most of the time, so they’re in a position to use quite a lot of their heavy-duty appliances during daylight hours). The 10.2kW system produces enough energy to cover all the usual household daytime usage (washing machine, clothes dryer, dishwasher, air-conditioning, refrigeration, etc), as well as charging the BYD Atto 3, filling the battery and heating the household water (c/o a Sanden heat pump, which exclusively runs from surplus solar energy). The credits they achieve over spring, summer and autumn go towards covering their winter electricity usage and supply charges, when their consumption is higher.
Before getting an EV, they were quite low electricity users. But the EV requires quite a lot of energy to charge (60kWh), so Caro figured it was better to oversize the system. This investment has paid off, with an average of 0.0006% of their energy usage coming from the grid – even when the car is being charged.
One of the reasons she went with SolarEdge optimised inverter technology is because she wanted the option of expanding her system down the track and she didn’t want to be impacted by “export limitation” (she’s in the Endeavour Energy area and the property only has single phase power, which means she can only export a maximum of 5kW back to the grid at any moment in time). When she and her partner added a SolarEdge battery, they were able to keep their original inverter and expand their system – and not be affected by export limitation.
Caro encourages all of her clients to follow the same 5 step process when buying a solar power and battery storage system that she’s followed for her own home:
- Buy good quality components
- Oversize your system a little to give you a buffer for lowlight days
- Where possible, self-consume your free solar power during the day
- Draw down on your stored energy in your battery when required; and
- Join a Virtual Power Plant and get paid incredibly well when the grid is under stress
Daily Energy Balance
From the 17/09/2023 to the 23/10/2023.
