Kiln Electricity Cost Calculator: What Does One Firing Cost?

How the kiln electricity cost calculator works

The kiln electricity cost calculator follows the method kiln maker Skutt publishes: multiply the kiln’s power in kilowatts by the firing time in hours, then by an adjustment factor for how much of that time the elements are actually on, then by your price per kilowatt hour. The result is the energy the firing uses, and its cost.

With the defaults, a Tetlow K2FL rated at 3.6 kW, an 8 hour firing and a factor of 0.6, that’s 3.6 times 8 times 0.6, or 17.28 kWh. At the United Energy flat rate of 27.35 cents per kWh, it costs about $4.73. Divide by the 10 kg of ware in the kiln and you get 47 cents a kilogram. Four firings a month comes to about $18.90, or around $227 a year.

The calculator also shows the full-power figure, here about $7.88, which is the most the firing could cost if the elements never switched off. Real firings land well below it, because the controller switches the elements on and off to follow its schedule.

How much does it cost to fire a kiln in Victoria?

At Victoria’s default flat rate, an 8 to 12 hour firing costs about $4.50 to $7 in a small 3 to 4 kW kiln, $8.50 to $13 in a mid-size 6.5 kW kiln and $14 to $22 in a large 11 kW three-phase kiln. The biggest factors are the kiln’s size, how long the firing runs and whether you fire on a flat rate or a time-of-use plan.

The rates built into the tool are the Victorian Default Offer for 2026-27, the regulated price the Essential Services Commission sets for each distribution area. In the United Energy area, which covers Mordialloc and much of Melbourne’s south-east, the flat rate is 27.35 cents per kWh. Other areas range from 25.96 cents with CitiPower to 31.98 cents with AusNet. A comparison site put the Melbourne average across market offers at about 25.85 cents in October 2026, so many households pay a little less than the default.

A typical 8 hour bisque in a 3.4 kW Woodrow DK30 uses about 16 kWh and costs about $4.46 at the flat rate. A 12 hour glaze firing in a Skutt KM818, at about 6.5 kW, uses about 47 kWh and costs around $12.80. These are small sums against the cost of the kiln itself, but they add up over a year of weekly firings.

What is the duty factor, and why 0.6?

The duty factor is the share of the firing time the elements are actually drawing power, and 0.6 is a sensible middle estimate. Skutt suggests an adjustment factor of 0.5 to 0.7 for its kilns, because the controller pulses the elements to follow the firing schedule rather than running them flat out.

Early in a firing, during slow warm-up segments, the elements are off much of the time. Near the top of a glaze firing they run almost continuously, fighting heat loss through the walls. A slow bisque with a long candling stage might average close to 0.5, while a fast glaze firing in an older kiln with worn elements might be nearer 0.7 or more.

We flag 0.6 as an assumption rather than a fact. If your kiln controller logs energy use, or you can read your meter before and after a firing with nothing else running, use your own figure. That one measurement makes the calculator far more accurate than any published average.

Does firing off-peak save money?

Yes, if you’re on a time-of-use plan and the firing fits inside the cheaper window. On United Energy’s default time-of-use rates, the same 17.28 kWh firing costs about $3.83 off-peak, $2.98 in the solar soak window from 11am to 4pm, and $6.97 at the 4pm to 9pm peak rate.

The catch is that firings are long. An 8 hour glaze firing started at 9pm finishes around 5am, comfortably off-peak, and the hottest, most power-hungry hours fall in the cheapest window. Started at 11am, the same firing runs into the evening peak just as the elements work hardest. Most kiln controllers have a delay-start setting for exactly this reason.

If you have rooftop solar, a daytime bisque can run partly on your own generation, which changes the sums again. In that case, the calculator’s figure is the upper limit, and the real cost depends on how much of the firing your panels cover.

Bisque vs glaze: cost per firing and per kilogram

A glaze firing usually costs more than a bisque, because it runs hotter and the kiln loses more heat at cone 6 than at cone 06. The longer, higher end of the schedule is where the elements run nearly flat out, so a glaze firing usually costs noticeably more than a bisque in the same kiln. Enter each schedule’s length separately to see the difference for your own firings.

The cost per kilogram is the most useful figure for pricing your work. At 47 cents a kilogram, a 400 g mug carries about 19 cents of electricity for each firing, or under 40 cents across a bisque and a glaze. A half-empty kiln costs nearly as much to fire as a full one, so packing the kiln well is the easiest saving of all.

That’s also why shared firings make sense for many potters. When the electricity is split across a full kiln, each piece costs very little. If you fire only occasionally, a kiln firing service may cost less than running your own kiln half full.

Common mistakes when costing a kiln

The most common mistake is using the kiln’s full rating for the whole firing, which overstates the cost by around two thirds if the real duty factor is 0.6. The second is forgetting that the daily supply charge is paid whether the kiln runs or not, so it isn’t really a firing cost, though it is part of your bill.

The third is ignoring installation. Woodrow, an Australian maker, says all its kilns need a dedicated connection like an oven or an air conditioner, because a normal power point is rated at only 10 amps. Larger kilns can need a three-phase supply. The electrician’s quote can be a bigger number than years of electricity, so get it before you buy. The pyrometric cone chart will help you plan the firing temperatures that drive these costs.