An electric geyser uses about 2.5 units (kWh) to heat a 50 litre tank from winter tap temperature, and about 2.3 units for every 10 minute hot shower. For a family of four, that typically adds 120 to 300 units a month in winter, which at 2026 tariffs can mean several thousand rupees on your bill.
This guide shows how to work out your own geyser's consumption, what it costs at current NEPRA rates, and the simple habits that bring it down. You can compare models in our electric geysers collection.
The simple formula
There are two easy ways to estimate a geyser's units.
From the wattage: units = watts ÷ 1000 × hours the element runs. A 1500W geyser that heats for 2 hours a day uses 3 units a day, or 90 units a month.
From the water you heat: raising 1 litre of water by 1°C takes about 1.16 watt-hours. So units = litres × temperature rise × 1.16 ÷ 1000. This version is better because it doesn't depend on guessing how long the element runs.
Units to heat a full tank
In a Punjab winter, tap water is around 12°C and most people set the geyser to about 55°C, a rise of about 43°C.
| Tank size | Units per full heat-up | Time at 1500W | Time at 2000W |
|---|---|---|---|
| 15 L | about 0.75 | about 30 min | about 22 min |
| 30 L | about 1.5 | about 1 hour | about 45 min |
| 50 L | about 2.5 | about 1 hr 40 min | about 1 hr 15 min |
| 80 L | about 4.0 | about 2 hr 40 min | about 2 hours |
| 100 L | about 5.0 | about 3 hr 20 min | about 2 hr 30 min |
Check your model's wattage on the product page or rating plate. For example, the Signature WH50R and Signature WH100R are both 1500W models. Heating times are shorter in summer, when tap water is warmer.
Units per shower and per month
What really drives your bill is how much hot water you use, not the tank size.
- A 10 minute shower at about 7 litres per minute and 40°C uses about 2.3 units.
- A bucket bath of about 25 litres at 40°C uses about 0.8 units.
- A storage tank also loses heat while it waits, roughly 0.5 to 1 unit a day depending on its insulation and thermostat setting.
| Household (winter) | Approx. units per month |
|---|---|
| 1 to 2 people, bucket baths | 40 to 70 |
| 2 people, daily showers | 150 to 160 |
| Family of 4, bucket baths | about 120 |
| Family of 4, daily showers | about 300 |
What it costs on your bill
Pakistani electricity is billed in slabs, so the cost of geyser units depends on where they push your total. Under NEPRA's 2026 base tariff for non-protected domestic consumers:
| Monthly units | Base rate per unit |
|---|---|
| 101 to 200 | Rs 28.91 |
| 201 to 300 | Rs 33.10 |
| 301 to 400 | Rs 37.99 |
| 401 to 500 | Rs 40.22 |
| Above 700 | Rs 47.69 |
These are base rates before fuel price adjustments, GST and other charges, so your actual cost per unit is higher. As a rough guide, every 100 geyser units landing in the 301 to 400 slab adds about Rs 3,800 in energy charges alone. A family of four on daily showers could add around Rs 11,000 or more before taxes.
The bigger risk is crossing slabs. If your winter bill is around 180 units without a geyser, adding 150 geyser units moves your whole household into a higher bracket.
How to cut your geyser bill
- Lower the thermostat. 50 to 55°C is hot enough for bathing. Every few degrees lower cuts both heating and standby losses.
- Heat on a schedule, not all day. Switch the geyser on about an hour or two before the family bathes and off afterwards. A geyser left on 24 hours keeps paying for heat lost through the tank.
- Pick the right size. A 100 L tank for two people wastes units keeping unused water hot. Our guide on what size geyser you need helps you match tank to family.
- Insulate exposed hot water pipes, especially on rooftops and outside walls.
- Descale the tank and element. Hard water builds up scale that makes the element work longer for the same heat. Drain and flush the tank before each winter.
- Fix dripping hot taps. A slow drip means the geyser keeps reheating cold water that flows in.
- Install the geyser close to the bathroom. Long pipe runs waste hot water while you wait for it to arrive.
- Use gas when you have it. A gas and electric hybrid lets you heat on gas during good-pressure hours and only use electricity as backup. See gas vs electric geyser for the full cost comparison.
Lower-running-cost alternatives
If electricity costs are the main worry:
- Instant gas geysers use no electricity and have no tank losses. See our instant gas geysers collection, starting with the Bold 6L BO2006N-LPG and Canon 6L 16DD-LPG.
- Hybrid geysers switch between gas and electricity. Compare the Bold 35GTWIN-HD-AI and others in our electric and gas geysers collection.
- Smaller electric tanks for single users, like the Boss KE-15CL Supreme, heat up in about half an hour and lose less heat.
- Models with timers or smart controls, such as the Midea D30-20EFG, make scheduled heating easier. Check each product page for its exact features.
Frequently asked questions
How many units does a geyser use per hour?
A geyser uses its wattage divided by 1000 for every hour the element is on. A 1500W geyser uses 1.5 units an hour; a 2000W geyser uses 2 units. Once the tank is hot, the element switches off and on only to top up lost heat.
Should I keep my electric geyser on all day?
Generally no. Heating the tank shortly before use and switching it off afterwards saves the standby losses of a tank kept hot for hours nobody uses it.
Does a bigger geyser use more electricity?
Only a little more for the same hot water use, mainly through higher standby losses. What you pay for is the hot water you actually use, plus the heat the tank loses while waiting.
How long does an electric geyser take to heat water?
About 30 minutes for a 15 litre tank and about 1 hour 40 minutes for a 50 litre tank on a 1500W element in winter. Higher-wattage models are faster.
Is an electric geyser expensive to run in Pakistan?
It can be. At 2026 tariffs, a family of four can add several thousand rupees a month in winter. Gas, hybrid or a right-sized tank with scheduled heating keeps the cost down.
Choose an efficient geyser
Browse every in-stock model in our geyser collection, or read our geyser buying guide to compare types, sizes and prices.
