Bisque vs Glaze Firing Cost Calculator
Instantly estimate your kiln electricity costs for bisque and glaze firing. Understand your energy consumption and optimise your pottery studio budget.
Calculate Your Kiln Energy Costs
Enter your kiln specifications and firing schedules. The calculator instantly estimates the electricity cost per fire and projects your monthly expenses.
Kiln Cost Estimator
Compare the energy costs of your bisque and glaze cycles.
Understanding Kiln Energy Use
Key factors that influence your electricity bill
Wattage and kWh
Your kiln’s wattage (e.g., 6000W or 6kW) is the maximum power it draws. Energy is billed in kilowatt-hours (kWh), which is the power used over time.
The Duty Cycle
Kilns do not draw maximum power continuously. As they approach the target temperature, the elements cycle on and off. A 60% duty cycle is a safe average for calculations.
Bisque vs Glaze Duration
Bisque fires are typically slower (8-12 hours) to allow physical and chemical water to escape without cracking the clay. Glaze fires are often faster (6-8 hours) but reach higher temperatures.
Heat Loss Factors
Older kilns with worn bricks or damaged element groves lose heat faster, forcing the elements to stay on longer and increasing the effective duty cycle and cost.
Typical Firing Profiles
Generalised averages for standard ceramic firings to help you contextualise your own kiln schedules.
| Firing Type | Target Temperature | Cone Equivalent | Typical Duration | Primary Goal |
|---|---|---|---|---|
| Bisque Fire | ~960°C – 1060°C | Cone 06 – 04 | 8 – 12 Hours | Drive out moisture, harden clay for glazing |
| Low Fire Glaze | ~1000°C – 1100°C | Cone 06 – 03 | 6 – 8 Hours | Melt earthenware glazes, vibrant colours |
| Mid Fire Glaze | ~1180°C – 1220°C | Cone 4 – 6 | 6 – 8 Hours | Vitrify stoneware, durable functional ware |
| High Fire Glaze | ~1280°C – 1300°C | Cone 10 | 8 – 10 Hours | Full vitrification, porcelain, reduction effects |
Kiln Cost Calculator FAQ
Answers to the most frequently asked questions about estimating ceramic kiln electricity costs.
Kiln firing cost is calculated by determining the total energy consumed in kilowatt-hours (kWh). The formula is: (Kiln Wattage / 1000) × Firing Duration (hours) × Duty Cycle (%) × Electricity Rate per kWh. The duty cycle accounts for the fact that kiln elements cycle on and off to maintain temperature.
Not always. While glaze firing reaches a higher temperature, it is often shorter in duration than a bisque fire. Bisque firing requires a slow ramp-up to drive out physical and chemical water, often taking 8-12 hours, whereas a glaze fire might take 6-8 hours. The cost depends on your specific kiln’s wattage and the exact schedules used.
The duty cycle is the percentage of time the kiln’s heating elements are actually drawing full power during a firing. As the kiln approaches its target temperature, the elements cycle on and off. An average duty cycle of 50% to 60% is commonly used for cost estimation.
You can reduce costs by fully loading the kiln to maximise efficiency per piece, ensuring kiln shelves and bricks are in good condition to retain heat, using an off-peak electricity tariff if available, and avoiding unnecessarily long hold times at peak temperature.
This calculator focuses specifically on the primary kiln heating elements, which account for the vast majority (typically 95%+) of the energy used during a firing. Ventilation fans consume a relatively negligible amount of electricity in comparison.
