Is installing a battery worth it?
A client recently posed the question: “Is it worthwhile to install a battery with my solar PV”? Well, it depends.
For the client in question, they run a large number of cold stores around Australia. So, their load is fairly constant, and applies around the clock and on weekends. But this was an investigation for a specific site in Western Sydney.
Normally, demand tariffs apply 24/7 but after looking at the tariff from Endeavour Energy, the maximum demand applied from 1pm to 8pm, working weekdays.
Using a model of the battery to correctly account for the costs of charging and discharging was essential. The model incorporated the actual site demand, predicted output from the solar PV system and determined the new monthly electricity bills for a number of different scenarios.
Along the way, we were able to answer a number of questions:
- what was the best battery technology?
- lithium ion
- redox flow
- what was the optimum size of the battery?
- how would the battery operate in conjuction with the solar array?
In this case, “best” included attributes of installation cost, performance deterioration and refurbishment cost. In the end, lithium-ion came out as the winner (for this client) but it is clear that there are a range of novel technologies out there seeking to establish a presence.
In the end we concluded that there was probably a role for storage and release of energy, but doing it using current technology was not compelling right now. The client is now making allowance for future inclusion of batteries in the facility plan.