The pool pump tax
A typical WA residential pool pump runs 6–8 hours daily at 1.0–1.5 kW continuous draw. That's 8–10 kWh per day, every day. At Synergy's flat-rate Home Plan A1 (~32c/kWh), that's $940–$1,170 per year just to keep the water moving. Heated pools push that closer to $1,500/year.
Most homeowners don't realise this because the pump runs in the background. It's easily 25–40% of your total annual electricity bill if you have a pool.
Why a battery is particularly good for pool households
Three reasons:
- The pump load is predictable. Unlike aircon (which spikes erratically), the pool pump draws a known number of kWh on a known schedule. A battery can be sized exactly to cover it.
- It runs during daylight hours. If you schedule the pump for 10am–4pm, it runs directly off solar - no battery needed during the day. Excess solar charges the battery for evening household loads.
- The pump can shift to off-peak. On Smart Home Plan, run the pump 9pm–5am (off-peak rates) and let the battery cover whatever overlap with peak hours.
Three configurations that work
Configuration A: Solar-direct pool + battery for the house
Best for: 6.6 kW+ solar systems, daytime pool scheduling, household with evening peak load.
How it works: Pool pump runs 10am–4pm directly off solar. Battery captures excess solar generation. Battery covers household 4pm–10pm evening peak. Grid only kicks in during overcast days.
Battery sizing: 10–13.5 kWh covers evening household load.
Configuration B: Pool runs from battery during peak rates
Best for: Smart Home Plan customers, year-round pool use, no flexibility on pump timing.
How it works: Battery is sized big enough (16–20 kWh) to cover both pool pump and household evening load during peak hours. Battery charges from off-peak grid overnight + midday solar.
Battery sizing: 16–20 kWh.
Configuration C: Pool runs overnight off-peak only
Best for: Cost-sensitive setups, simpler installs, partial benefit.
How it works: Reschedule pool pump for 9pm–5am off-peak window (Smart Home Plan). Battery covers household evening load only.
Battery sizing: 10–13.5 kWh for household, pool just runs off cheap grid.
The maths for a pool household
Take a Perth Synergy household with a 6.6 kW solar system, 13.5 kWh battery, pool pump running 7 hours/day, $850/quarter bill:
- Pool electricity cost without changes: ~$1,100/year
- Pool electricity cost with solar-direct scheduling + battery: ~$300/year
- Net battery cost after rebates: ~$4,000
- Annual household + pool savings: ~$1,900
- Payback: ~2.1 years. Pool households see the fastest battery paybacks in WA.
What to ask your installer
- "Will the battery support the continuous load of my pool pump (1.2–1.5 kW)?" - most modern batteries do, but verify.
- "Can you set up smart scheduling so the pump runs from solar when available?" - yes, with Fronius/SolarEdge/Tesla integrated solutions.
- "What's the optimal pump schedule for a 6.6 kW solar + 13.5 kWh battery setup?" - a good installer will model this for you.
- "Do I need a smart consumption meter to make this work?" - usually yes for advanced scheduling.
Heat pump pool warmers - the bonus play
If you currently heat your pool with gas (or have unheated water but use the pool year-round), a heat pump pool heater paired with your new solar + battery setup is a powerful combination. Heat pumps draw 1.5–3 kW for heating, which solar + battery covers cleanly. Annual gas savings can be $1,500+. Talk to your installer about quoting a heat pump alongside the battery install.