How much does it cost to run a continuous flow electric water heater?
A typical continuous flow electric water heater draws about 3000 watts. Used 0.5 hours a day, that works out to roughly $0.26 per day, $7.76 per month, and $93.08 per year on an average electricity rate of 17¢ per kWh. Tankless electric water heaters draw 2000-5000W when in use for instant hot water delivery.
Continuous Flow Electric Water Heater running cost calculator
- Per day
- $0.26
- Per month
- $7.76
- Per year
- $93.08
- CO₂ / year
- 219 kg
Based on 547.5 kWh per year. Adjust the price per kWh to match your latest electricity bill for an exact figure.
The number that matters most is your own electricity rate. Rates range from under 11¢ per kWh in some regions to over 30¢ in others, so the same continuous flow electric water heater can cost two or three times as much depending on where you live. Enter your exact rate in the calculator above to get a figure tailored to your bill.
In the kitchen the continuous flow electric water heater is typically used in short, frequent bursts rather than left on all day, so total run time matters more than peak wattage. Small changes — batching tasks, matching the appliance to the job — add up over a year of daily cooking.
At 3000 watts, the continuous flow electric water heater is a high-draw appliance — the kind that can briefly become the single biggest load in your home while it runs. On a time-of-use tariff, shifting it to off-peak hours is often the easiest way to cut its cost without using it any less.
Over a full year this continuous flow electric water heater uses about 547.5 kWh of electricity and is responsible for roughly 219 kg of CO₂ emissions on an average grid. Because it runs more or less year-round, even a small reduction in daily use carries straight through to a lower annual total.
To put the draw in everyday terms, one hour of running this continuous flow electric water heater uses about as much electricity as charging a smartphone 250 times. It is a rough comparison, but it makes an abstract wattage figure easier to picture.
If this continuous flow electric water heater is one you use daily, even small efficiency gains compound. Cutting its usage or wattage by 20% would save around $18.62 every year — money that an efficient replacement can recover over its lifetime.
Frequently asked questions
- How much does it cost to run a continuous flow electric water heater per hour?
- At 3000 watts and a 17¢/kWh rate, a continuous flow electric water heater costs about $0.51 per hour to run.
- How much electricity does a continuous flow electric water heater use per month?
- Running 0.5 hours a day, a continuous flow electric water heater uses roughly 45.6 kWh per month, costing about $7.76.
- How many kWh does a continuous flow electric water heater use per year?
- Used 0.5 hours a day for 365 days a year, a continuous flow electric water heater consumes about 547.5 kWh annually — that is the figure your electricity rate is multiplied by to get the $93.08 yearly cost.
- Is a continuous flow electric water heater expensive to run?
- Not particularly — at around $93.08 per year, a continuous flow electric water heater is a relatively minor part of most electricity bills.
- How much CO₂ does a continuous flow electric water heater produce?
- On an average grid, a continuous flow electric water heater used this much is responsible for roughly 219 kg of CO₂ per year. The exact figure depends on how clean your local electricity supply is.
- How can I reduce my continuous flow electric water heater running costs?
- Use it during off-peak hours if your utility offers time-of-use pricing, reduce daily run time, and consider an ENERGY STAR rated continuous flow electric water heater, which uses less power for the same job.