This calculator estimates how much electricity your rice cooker uses for each batch of rice and how that translates into cost. By entering the rice cooker wattage, typical cooking time per batch, your electricity price, and how many batches you cook per week, you can see both per-batch and weekly electricity expenses.
The tool is designed for quick budgeting and for comparing different cooking habits, such as cooking one small batch every day versus a few larger batches per week. It can also support decisions about which rice cooker to buy or how to size an off‑grid or solar power system.
Once you enter these values, the calculator estimates the energy used per batch (kWh), the cost per batch, and the total weekly cost based on how many batches you cook.
The core idea is to convert the rice cooker’s wattage and cooking time into energy in kilowatt‑hours, then multiply by your electricity rate.
The energy per batch is calculated as:
Where:
The formula divides by 60 to convert minutes to hours, and by 1,000 to convert watts to kilowatts. Once the energy is known, the cost per batch is:
Cost per batch ($) = E (kWh) × electricity rate ($/kWh)
The weekly cost is then:
Weekly cost ($/week) = Cost per batch × batches per week
Imagine you have a 700 W rice cooker that takes 40 minutes to cook a batch. Your electricity rate is $0.13 per kWh and you make four batches per week.
E = 700 W × 40 min ÷ 60 ÷ 1000E ≈ 700 × 40 ÷ 60 ÷ 1000E ≈ 28,000 ÷ 60 ÷ 1000 ≈ 0.47 kWh
Cost per batch = 0.47 kWh × $0.13/kWh ≈ $0.06
Weekly cost = $0.06 × 4 ≈ $0.24 per week
In the calculator, you would see approximately 0.47 kWh and $0.06 for each batch, and about $0.24 as your total weekly cost.
For comparison, if you cooked the same rice on a 1,500 W stove burner for 40 minutes, the energy per batch would be roughly:
E ≈ 1500 × 40 ÷ 60 ÷ 1000 ≈ 1.0 kWh
At $0.13/kWh, that is about $0.13 per batch—more than double the rice cooker in this example.
The calculator focuses on three main outputs:
To put things into context, if your weekly rice cooking costs around $0.50, that is about $2 per month. On an electricity bill of $100 per month, rice cooking would be only about 2% of your total bill. While the per‑batch cost is small, it can be useful to compare different appliances or routines when you are trying to manage energy use carefully.
The table below illustrates how weekly energy use and cost can change with how often you cook rice, assuming a typical 700 W cooker, 40‑minute batches, and an electricity rate of $0.13/kWh (the same assumptions as in the example above).
| Batches per week | Energy per week (kWh) | Cost per week (USD) |
|---|---|---|
| 1 batch | 0.47 kWh | $0.06 |
| 3 batches | 1.41 kWh | $0.18 |
| 7 batches | 3.29 kWh | $0.43 |
Use this as a rough guide. Your exact values will differ based on your cooker’s wattage, cooking time, and local electricity price. By entering your own numbers into the calculator, you can generate a personalized version of this kind of scenario table.
If you are comparing two models—for example, a 500 W cooker that takes 50 minutes versus a 900 W cooker that takes 25 minutes—you can plug each set of values into the calculator. Even though the higher‑wattage cooker uses more power at any instant, it might use a similar or even lower total energy if it cooks faster. The per‑batch kWh output helps you compare fairly.
You can also estimate the cost of alternatives like stove‑top pots, induction cookers, or microwaves by entering their approximate wattage and cooking time as if they were “rice cookers”. While this is a simplification, it provides a quick way to see whether an appliance is likely to use more or less energy per batch.
For solar or battery systems, the energy per batch (kWh) and weekly kWh are especially important. Multiply the weekly kWh by 52 to estimate annual energy use. You can then compare this to your solar generation or battery storage capacity to decide whether frequent rice cooking is practical in your setup.
This calculator provides reasonable estimates, but it does rely on some simplifying assumptions:
Understanding these assumptions helps you interpret the numbers correctly and avoid overestimating the precision of the results.
After you explore how much energy and money each batch of rice uses, you can try adjusting the inputs to see how changes in batch size, cooking time, or frequency affect your weekly cost. You may find that cooking a slightly larger pot less often barely changes energy use, but simplifies meal prep.
For a broader view of your kitchen’s energy use, consider using similar tools for other appliances like electric kettles, slow cookers, or ovens. Comparing the per‑batch and weekly costs across appliances can help you make small, practical changes that add up to noticeable savings over time.