Hydroponic Running Cost Calculator
The electric bill is the cost most new growers worry about, and it is usually the small one. A countertop light costs less than a coffee a month to run, while replacement seed pods can quietly cost more than everything else put together.
This free hydroponic running cost calculator adds up your electricity, nutrients and pods or seeds for a month and a year. Pick where you live and a starting setup, change any number to match yours, and the total updates as you type.
Where do you live?
What runs on electricity?
Start from a setup, then change anything that does not match yours.
Nutrients
Prefilled with the General Hydroponics Flora Series set (three 16 oz bottles, 1,419 ml together) at its current Amazon price, dosed for EC 1.4, the middle of the range for herbs and leafy greens. Another brand? Type its dose from the label and its price.
Pods or seeds
Herbs from pods usually keep producing for two to three months. Replanting a jar of lettuce after each harvest counts as a new start.
Your running cost
Where the money goes
Electricity by device
| Device | kWh a month | Cost a month |
|---|
Plug your light or pump into it and it shows the real watts and kWh, so you can type true numbers into the calculator.
Holds the light to the hours your crop needs, so it never burns all night by mistake.
The concentrate the nutrient line is based on. A small system uses very little of it each month.
Empty pods for your own seeds, cheaper than pre-seeded kits.
The cheapest per pod of the two, if your garden takes standard pods.
🔎 Research picks, chosen from published specifications and listings. Prices are pulled from Amazon and were last checked on 8 October 2026 at 8:47 pm. Amazon prices change often, so check the listing before buying. How I test and choose products.
How to use this hydroponic running cost calculator
- Pick your country. The electricity price fills in with an official average for the US, the UK price cap, Ontario for Canada, or New South Wales for Australia. Replace it with the rate on your bill for the most accurate result.
- Choose a starting setup, then edit the devices. Each line is a light, pump or fan: how many you run, the watts on the label, and the hours a day it is on. Air pumps run all 24 hours.
- Check the nutrient line. Enter your reservoir size, how often you mix a fresh batch, the dose from your bottle and what the bottle cost.
- Add pods or seeds. Count the plants growing at once, how many months each lasts, and what one start costs. The total and the breakdown update as you type, and the link to your setup saves every number.
Where these numbers come from
- US price: 18.2 cents per kWh, the average US home price for January to July 2026 in the EIA Electric Power Monthly, table 5.3 (18.19 cents, rounded).
- UK price: 26.32p per kWh, the Ofgem price cap unit rate for 1 October to 31 December 2026, direct debit, Great Britain average.
- Canada price: 12.0 cents per kWh, the Ontario Energy Board regulated price, tier 1, for 1 November 2025 to 31 October 2026. It covers electricity only; delivery and regulatory charges are extra.
- Australia price: 38.3 cents per kWh, the ACCC median effective price for New South Wales homes, July to September 2025, excluding rebates and GST (Inquiry into the National Electricity Market, June 2026, table 2.1). It includes the daily supply charge spread over usage, so the cost of each extra kWh is usually a little lower.
- Wattages: the Amazon listings for the Mars Hydro TS600 (100 W), Spider Farmer SF1000 (100 W), VIPARSPECTRA P700 (70 W), VIVOSUN T5 strip (7 W) and hygger dual-outlet pump (5 W); the countertop lights (AeroGarden Harvest 20 W, Click & Grow Smart Garden 3 8 W) from the countertop systems guide. The Click & Grow light follows the maker’s preset timer, 16 hours on and 8 off by its listing, so its preset uses those hours.
- Nutrient dose: about 2.7 ml per liter of the three Flora Series parts together for each 1.0 of EC, from the General Hydroponics feed chart as used in the pH and nutrient calculator. EC 1.4 gives 3.8 ml per liter, or 14.3 ml per gallon.
- Light hours: 14 a day for herbs and leafy greens, and a fresh batch every two weeks for pumped and countertop systems, the same rules every guide on this site uses. A month here is 30.4 days.
Common questions about hydroponic running costs
How much electricity does a small hydroponic system use?
Mostly what the light uses. A 20 W countertop light on for 14 hours a day uses about 8.5 kWh a month, a 100 W LED panel on the same schedule about 42.6 kWh, and a 5 W air pump running all day about 3.7 kWh. At the US average of 18.2 cents per kWh that is roughly $1.55, $7.75 and 66 cents a month.
Does an AeroGarden use a lot of electricity?
No. The Harvest’s 20 W light on a 14-hour timer comes to about 8.5 kWh a month, around $1.55 at the US average price. In a typical 6-pod garden replanted every few months, the replacement seed pods cost more each month than the power does.
Should I turn the air pump off at night to save money?
No. Roots in an aerated system need oxygen around the clock, so the air pump runs 24 hours a day. A 5 W pump costs well under a dollar a month at the US average price, far less than one lost plant. Kratky jars are the exception because they use no pump at all.
What costs more, nutrients or electricity?
Electricity, and often the pods or seeds too. A 1-gallon reservoir mixed fresh every two weeks uses only about 31 ml of a three-part concentrate a month, so one set of 16 oz bottles lasts years in a small system. A 6-pod garden replanted every three months, on the other hand, goes through a whole pod kit each season.
Where do I find my electricity rate?
On your bill. Look for the price per kWh, or divide the energy charge by the kWh used. In the UK the unit rate is printed on the bill and follows the Ofgem price cap. In Canada prices differ a lot by province, and Ontario bills add delivery charges on top of the electricity price, so the all-in rate is higher than the electricity line alone. Australian bills list the usage rate in cents per kWh apart from the daily supply charge.
How accurate is this calculator?
As accurate as the watts and hours you give it. The presets use the wattage printed on each product listing, and a plug-in power meter shows what your light and pump really draw from the wall. Standing charges, taxes and water are left out: a small reservoir uses a few gallons of tap water a month, which costs pennies.