Electric geyser (storage water heater): units per month in Pakistan
Short answer. A 2,000 watt electric geyser used for two hours a day costs 4 units daily and about 120 units a month. Left on continuously, the element cycles for around nine hours a day to hold a tank of water hot that nobody is using — roughly 18 units a day and 540 units a month. In most Pakistani homes with an electric geyser, this is the largest winter load by a wide margin.
Power draw
- Low: 1500 W
- Typical: 2000 W — the figure used in every calculation below
- High: 3000 W
Element rating. A 30-gallon domestic geyser is usually 2,000 W; larger and twin-element units reach 3,000 W.
Units and cost by usage pattern
Each row is 2000 W × the hours shown ÷ 1,000, over 30 days. The three cost columns exist because the rupee cost of a unit depends entirely on which slab your month lands in — the same consumption costs a light user and a heavy summer household very different amounts. Rates are illustrative and not a substitute for the tariff table printed on your own bill.
| Usage pattern | Units / day | Units / month | At Rs 12.5/unit | At Rs 27.5/unit | At Rs 36/unit |
|---|---|---|---|---|---|
| Timer, one hour before each of two bathing times | 4 | 120 | Rs 1,500 | Rs 3,300 | Rs 4,320 |
| Switched on in the morning and left on until night | 12 | 360 | Rs 4,500 | Rs 9,900 | Rs 12,960 |
| Left on continuously (element cycling to hold temperature) | 18 | 540 | Rs 6,750 | Rs 14,850 | Rs 19,440 |
Rate bands: Rs 12.5 — light user, protected (≈150 units/month); Rs 27.5 — average household (≈250 units/month); Rs 36 — heavy summer month (700+ units). This appliance is seasonal — the usage patterns above assume 5 months of the year at most, so the annual figure is lower than twelve times the monthly one.
Standby loss is the whole problem
A storage geyser holds thirty or so gallons at temperature. Heat leaks out through the tank wall continuously, and the element switches back on to replace it whether or not anybody has drawn a drop of water.
The energy that actually reaches your shower is a fraction of what the meter records. Everything else was spent keeping water hot at 3 am.
What a timer is worth
Going from continuously on to two heated hours a day takes the load from roughly 540 units a month to about 120. At a top-slab marginal rate that is a four-figure monthly saving from a device that costs very little.
A mechanical timer, or simply a disciplined switch on the wall, is the highest-return intervention available in a Pakistani home in winter. Nothing else on this list comes close.
Gas versus electric
Where a gas geyser is an option, it is almost always cheaper to run in Pakistan on a per-unit-of-heat basis. The counter-argument is gas load shedding in winter, which is precisely when the geyser is needed, and the safety risk of a poorly ventilated gas heater in a bathroom.
Households with both frequently use gas as primary and electric as backup. Doing the reverse — leaving the electric geyser on as a standby that is never turned off — is the expensive version of the same arrangement.
How to use less
- Fit a timer, or switch it on an hour before bathing and off immediately after. This single change is worth more than every other tip on this site combined for a winter bill.
- Insulate the tank and the first two metres of hot pipe. Jackets are cheap and cut standby loss materially.
- Set the thermostat to around 55–60 °C. Higher than that means you are heating water only to mix cold back into it.
- Fix dripping hot taps immediately — a drip on the hot side is a drip of paid-for heat.
- Consider an instant heater for a bathroom used briefly by one person; there is no tank to keep warm.
Frequently asked questions
Is it cheaper to leave the geyser on all day or switch it on when needed?
Switching it on when needed, decisively. The claim that reheating costs more than maintaining is false for a well-insulated tank — the standby loss over sixteen idle hours far exceeds the energy to reheat once.
How many units does a geyser use per hour?
A 2,000 watt element uses 2 units for each full hour it is actually on. Once the tank reaches temperature the element cycles, so a geyser switched on for three hours may only draw for one and a half of them.
Does a bigger geyser use more electricity?
For the same amount of hot water actually used, a larger tank costs more because there is more water and more surface area to keep hot. Size the tank to your household's real draw rather than to the biggest available.
Compare with
- Instant water heater — 4500 W typical
- Water pump (motor) — 750 W typical
- Electric room heater — 1800 W typical
Go further
Filed under water heating and pumping in the full appliance index. Add your own hours in the consumption calculator, or open your actual bill with the reference number lookup.