Electric Kiln Firing - Estimating Cost

Step 5: Calculation of Firing Electricity Cost
- Kiln KWatt x Firing Hours x Duty Cycle x Cost per KWH
- Preheating: 11.52 x 7 x 0.15 x 0.18 = $2.18
- Bisquing: 11.52 x 9 x 0.5 x 0.18 = $12.35
- Glazing: 11.52 x 10 x 0.65 x 0.18 = $13.48
- Total cost for candling, bisque (cone 06) and glaze firing (cone 6): 2.18+12.35+13.48 = $28.00

Step 6: Other Firing Costs
- Fans: Use the same calculation as above to figure out operating fans costs (about $1.00 for 24 for two fans)
- Kiln cost: Let’s assume that your kiln purchase cost is $2500 and lasted 400 firings. Cost per firing will therefore be $6.25
- Kiln maintenance: Elements, relays and thermocouple require replacement approximately every 100 firings (150 firings if used for low fire only). If you are able to use your own labor to replace parts, the cost for the above parts is about $375 (add $250 for labor). Cost per firing is therefore $3.75 or $5.75 (w/labor) per firing.
- Space used: If you rent space, monthly rental cost for the kiln room will add to “Per Firing Cost”. Let’s say your kiln room is 9x6’ = 54 sq ft. For example, if your rent is $2 a sq ft per month, the kiln room cost is $108 per month. If you fire 5 times a month, cost per firing is $21.60
- Insurance: Insurance cost for a house or a facility can double in some cases due to having a kiln. In our case (Lakeside Pottery), insurance cost increased by $1,200 a year. At a 5 times a month firing rate, the cost per firing will be $20.00
- Misc other costs: Kiln shelves maintenance (labor, parts and material), kiln wash, witness cones. For this example, let’s assume $2.00 per firing

Conclusion
If all variables are added up using the information above with a real situation example, cost per firing is way more than just the electric cost. For example, electric cost per glaze firing is $13.48. But, the total cost taking in all variables, adds up to $70 per firing ($13.48 + 1 + 6.25 + 5.75 + 21.6 + 20 + 2).

More tips and information about firing electric kiln: Firing Electric Kiln - kiln sitter or electronic control, instructions, tips and issues

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