How Much Electricity Does a Borehole Pump Use?

Running a borehole can cut your municipal water bill meaningfully — but it does shift some of that cost onto your electricity bill. Before you commit, it’s worth understanding exactly what a borehole pump draws, what that translates to in rands per month, and which equipment choices keep the figure reasonable.

How pump power is measured

Electricity consumption is quoted in kilowatts (kW) for demand and kilowatt-hours (kWh) for energy used over time. A pump rated at 1.1 kW running for two hours uses 2.2 kWh — the same unit your electricity meter counts. Your bill charge per kWh depends on whether you’re on a City Power residential tariff, a prepaid block rate, or a rural Eskom tariff; as a rough guide, most Johannesburg homeowners pay somewhere between R2.50 and R3.50 per kWh, but confirm your current rate on your latest statement or via Eskom’s published tariff schedule.

Typical power ratings for residential pumps

Submersible borehole pumps for homes generally fall into three broad categories:

Pump size	Typical motor rating	Likely application
Small	0.37–0.75 kW	Low-yield borehole, garden irrigation only
Medium	0.75–1.5 kW	Household use plus garden, most Joburg homes
Larger	1.5–2.2 kW	High-demand households, dual-purpose supply

Pumps beyond 2.2 kW exist but are uncommon in standard residential installations. The motor rating on the pump nameplate is the number that matters — ignore the inlet pressure figure for electricity calculations.

Borehole pump hardware and installation typically costs R15,000–R35,000 installed. If you want a fuller picture of what the whole system involves, the complete guide to borehole drilling in Johannesburg covers yields, casing, and system design in one place.

Calculating your monthly cost

The formula is straightforward:

Daily kWh = pump kW × hours run per day Monthly cost = daily kWh × 30 × your tariff (R/kWh)

As a worked illustration (not a guaranteed figure for your pump):

• A 1.1 kW pump running 3 hours a day = 3.3 kWh/day
• At R3.00/kWh: 3.3 × 30 × R3.00 = roughly R297/month
• At R3.50/kWh the same pump costs roughly R347/month

Run time is the variable most homeowners underestimate. A pump feeding a header tank typically cycles on and off; one feeding directly through a pressure vessel runs for shorter bursts. Either way, total daily runtime is what you need to estimate — your installer should help you model this against your household’s daily demand.

South Africans use on average about 237 litres per person per day (IWA Water Policy data), which is above the world average of roughly 173 litres. A household of four using the full average — around 950 litres a day — gives you a realistic baseline for sizing both your pump and your expected runtime.

Unsure which pump size suits your borehole yield and household demand? Compare 3 free quotes — vetted installers, no obligation.

What drives the bill up unnecessarily

Several common mistakes inflate electricity consumption:

Oversized pump. Installers sometimes fit a larger pump than the borehole yield warrants. An oversized pump draws more power every cycle and can cause the borehole to run dry, triggering automatic cutoff and restart cycles that waste energy.

No timer or float switch. Without a cut-off, a pump feeding a storage tank will keep running after the tank is full, burning electricity doing nothing useful. A simple float valve or timer adds little to the installation cost and pays back quickly.

Pumping directly into supply pressure. Constant-pressure pumps that respond to every tap opening run more frequently than systems that pump into an elevated or ground-level storage tank on a fill-and-stop cycle. Both approaches are legitimate, but the storage-tank approach typically results in fewer total running hours.

Old or worn pump. Motor efficiency drops as bearings wear and windings degrade. A pump that was efficient at installation may draw noticeably more current five years later.

Solar as a way to manage the electricity cost

If load-shedding or rising tariffs concern you, running a borehole pump on solar is increasingly practical in Johannesburg. The city’s solar resource is strong, and a correctly sized PV array can cover most daytime pumping. The trade-off is upfront capital cost and the need to match panel output to pump starting current, which is higher than running current. Read the full breakdown in solar-powered boreholes in Johannesburg before specifying a system.

Keeping ongoing costs in check

Electricity is only part of the running-cost picture. Pump maintenance, borehole water testing against SANS 241 (the 2024 South African drinking-water quality standard), and any treatment equipment all contribute. The detailed numbers are covered in borehole running costs, which walks through annual servicing, pump replacement cycles, and testing fees.

A few practical steps that genuinely reduce electricity use:

• Right-size the pump to the yield. Your driller’s yield test determines the safe sustained abstraction rate; the pump should match that, not exceed it.
• Install a pump controller or timer. Even a basic float switch on a storage tank eliminates wasted run time.
• Check starting current before choosing an inverter or solar system. Submersible pumps draw two to three times their rated current at startup; undersizing the inverter causes nuisance tripping.
• Log your meter reading. A simple monthly note of kWh consumed tells you immediately if consumption creeps up, which is often the first sign of a failing pump.

Ready to get actual cost estimates for your specific site? Get three installer quotes — vetted professionals, no pressure to commit.

The honest bottom line

For most Johannesburg households, a correctly sized borehole pump adds R200–R700 per month to the electricity bill — less if the pump is small and well-controlled, more if it’s oversized or runs without cutoffs. That figure needs to sit alongside the saving on your municipal water account and the value of supply security, given that Johannesburg Water’s own figures show 44.8% non-revenue water losses and the city’s reservoir system holds only roughly 27 hours of citywide storage buffer. Whether the numbers work for your situation depends on your specific pump size, daily demand, and tariff — which is exactly what a proper quote comparison should lay out for you.