While the cost of Eskom generated electricity is expected to increase dramatically following approval by Nersa for the recovery of R32.69-billion from consumers, the cost of solar PV generated electricity is plummeting, testing pay-back periods of less than 3 years for commercial solar inverter applications that have no storage capacity. However, off-grid battery inverters for typical home use have a longer pay-back period, therefore the choice of battery type is an important consideration. In this case study, we reviewed the benefits of deploying a Lithium Iron Phosphate (LiFePO4) energy storage solution.
Ms Tessa Davies from Harfield Village (Claremont) decided that she needed a more secure supply of electricity to counter load shedding, together with environmental considerations and a reduction in the cost of living, which prompted her to approach AWPower for a long-term energy solution. AWPower engineers designed and installed an off-grid Solar PV solution during October 2017.
As Tessa required a long-life maintenance free solution, a Freedom Won Lithium Iron Phosphate (LiFePO4) battery with capacity of 10kWh was chosen. This particular battery is maintenance free and comes with a 10-year guarantee. The battery was installed together with 3.1kW of PV modules (12 x 260Wp) and an MLT Oasis 6kW Off-grid Inverter with Nomad Controller.
Tessa reported that the average savings over a year since date of installation has been approximately R800 per month, where the average cost of electricity prior to installation of the solar PV solution was approximately R1,000 per month.
Tessa further commented:
“The solar PV system that AWPower installed has made management easier and made me more aware of my own poor use management. It did take a couple of months for me to understand the system, like running heavy loads such as washing machine, geyser, dishwasher etc. during the daylight hours, as previously I ran these appliances overnight, but I am comfortable with it now having been through a whole summer/winter cycle. Other benefits include adding value to the house.”
Tessa concluded “I checked the qualifications of those involved and was happy that the AWPower team were well qualified to do the job. Not fully understanding the system I asked many basic questions at first but they were always very prompt and professional with advice and call-outs. Together we tweaked the system to get the best performance for my requirements.”