Every new owner of an aerobic system eventually asks the same question, usually while looking at a power bill: how much is that thing in the yard costing me?
Most articles answer with a vague range. There is no need for that, because the two numbers you need are both published. Your pump’s nameplate tells you the watts. Your electricity bill gives you the price. The rest is multiplication, and you can do it for your own system in two minutes.
The short answer, with the arithmetic shown
An aerator that runs continuously can be a major electrical load. Check your model’s approved operating cycle before using the 24-hour example. Take a common unit as the worked example.
The manufacturer’s product listing for the Hiblow HP-80 gives a maximum flow of 120 litres per minute and a power consumption of 71 watts. Check the nameplate on your own pump: models and wattages differ.
Running continuously:
- 71 watts × 24 hours × 365 days = 622 kilowatt-hours a year
- To get a yearly cost, multiply the kilowatt-hours by the price per kilowatt-hour on your own electricity bill.
Here are the three sizes in that family:
| Model | Watts | kWh / year |
| HP-60 | 51 | 447 |
| HP-80 | 71 | 622 |
| HP-100 | 100 | 876 |
Those kilowatt-hours are the number to take to your bill. Your rate, and whether your model runs continuously or on a timed cycle, decide the cost.
Do it for your own system
Do not use our table. Use your pump.
- Find the nameplate on the pump housing, or the data sheet for your model. You want the figure in watts. If the plate gives only amps and volts, multiply them: 1.6 A × 120 V = 192 VA, which is not the same as watts for a motor, so prefer the stated wattage when it is printed.
- Annual kWh = watts × 24 × 365 ÷ 1000.
- Annual cost = kWh × your price per kWh. Take that price from your own bill, not from an average.
Write the result in your records. Our printable maintenance record has somewhere to keep it, and it belongs in the yearly figure described in our guide to aerobic septic maintenance costs.
What that figure does not include
The example assumes a continuously operating aerator. Three other things draw power, and none of them can be estimated honestly from a nameplate alone.
The effluent pump. It runs intermittently, only when the pump tank reaches its float. Its annual consumption therefore depends on how much water your household sends through the system, which is why nobody can give you a number for it without knowing your usage. If you want to estimate it, you need run hours, and some control panels log them. Our guide to how much water an aerobic system can handle explains why that loading governs so much.
Ultraviolet disinfection, if you have it. Where fitted, a UV lamp can add electrical load; use its rated wattage and documented operating schedule. Systems using chlorine tablets have no equivalent.
The control panel and alarm. Include their documented power consumption if it materially affects the estimate.
A reasonable way to think about it: the aerator figure is the floor, and the real total is somewhat above it.
The question you should not act on
Once an owner learns the aerator runs twenty-four hours a day, the next thought is almost always the same: could I put it on a timer, or switch it off at night?
No. And it is worth being precise about why, because the reasoning matters more than the instruction.
The U.S. Environmental Protection Agency describes an aerobic system as one that injects oxygen into the treatment tank, where the added oxygen increases bacterial activity and provides additional treatment. That bacterial population is a living thing with a continuous oxygen demand. Interrupt the supply and you are not pausing a machine, you are starving a culture. The treatment degrades, and what leaves your system moves back toward untreated wastewater, onto ground your family walks on.
There is a second reason. Your system is permitted on the basis of an approved design, and that design assumes the equipment runs as specified. In Texas, aerobic systems operate under a maintenance regime set by TCEQ rules; in Florida, under an operating permit that depends on a current maintenance agreement. Deliberately running the equipment outside its design is not a private economy, it is a modification of a permitted installation.
Use the manufacturer’s approved operating schedule; do not create your own energy-saving timer cycle.
How to reduce it legitimately
There are real savings available. None of them involve switching anything off.
- Keep the air filter clean. A restricted intake makes the pump work against resistance. It also shortens diaphragm life, which costs far more than the electricity.
- Keep the housing shaded and ventilated. Heat is what kills diaphragms early, and a struggling pump is an inefficient one.
- Replace a failing pump promptly. A pump with torn diaphragms draws power and delivers little air: you pay for electricity and get no treatment. The symptoms are in our guide to what happens when the air pump stops working.
- Match the pump to the design, not to the price. Fitting a larger unit than the design calls for means paying for air the system does not need, every hour, for years. Our component guide covers what each part does and why the rating matters.
- Spread your water use. It does not change the aerator, but it reduces effluent pump cycles.
Put it in perspective
Electricity is a running cost to include in your budget, alongside the maintenance contract, disinfection supplies and replacement parts. For the one-off side, see installation costs.
How these figures were calculated
Educational information only, and not a diagnosis of your system. The figures here are calculated from published manufacturer wattages, shown so you can repeat the calculation with your own numbers; they are not an estimate for your property. Your pump’s rating, your electricity tariff, your system design and your usage determine your actual cost. Your permit, your system manual, your permitting authority and a qualified provider determine how the equipment must be operated. This site does not encourage tank entry, electrical work, contact with untreated wastewater, or altering how a permitted system runs.
Sources
- Hiblow USA, pressure-pump product finder, for the HP-60 (51 W), HP-80 (120 lpm, 71 W) and HP-100 (100 W). Checked October 15, 2026.
- U.S. Environmental Protection Agency, Types of Septic Systems, for how aerobic treatment works and why the system requires electrical power.
- Texas Commission on Environmental Quality, OSSF maintenance guidance, 30 TAC §285.90.
Last reviewed: October 3, 2026. If a figure here no longer matches the manufacturer’s listing, tell us through our contact page and we will correct it.