The useful answerA long cooking time does not tell you the slow cooker running cost by itself. An illustrative average draw of 150 W over eight hours uses 1.20 kWh, costing about $0.22 at $0.18/kWh, before a separate keep-warm period.

Separate rated power from average power

The rating identifies electrical requirements; it does not necessarily describe the average draw over an entire recipe. Some controls cycle, and low, high and warm settings can behave differently across models. Write down which setting you used and whether the recipe required an initial period on a different setting.

If you measure a session, start with the appliance in its normal cold condition. Record food quantity, liquid quantity and total elapsed time so that a later measurement describes a reasonably comparable meal.

Put eight hours into kWh

For a hypothetical 150 W average, multiply 150 ÷ 1,000 × 8 = 1.20 kWh. At $0.18/kWh, electricity costs $0.216. Six servings would allocate about 3.6 cents of that cooking energy to each serving. This is an arithmetic example, not a typical consumption claim.

If a subsequent warm period averages 40 W for two hours, it adds 0.08 kWh and about 1.4 cents. Keep the periods separate so you can see what a schedule change actually affects.

Compare the whole recipe

Account for any electric hob used to brown ingredients before slow cooking. A pressure-cooker comparison should include its heat-up and finishing stages too. If one recipe makes twice as much food, compare per serving and include later reheating when evaluating the complete meal plan. Do not shorten a tested cooking process or change food-handling practices simply to meet an energy target.

Choose a measurement worth repeating

For a plug-in appliance, use an energy meter only if the connection is allowed by both manufacturers and the meter’s rating covers the load. One complete representative session is more useful than watching a momentary watt reading. Repeat when portion size or settings change, then multiply the measured session cost by your expected number of meals. A weekly habit produces a more useful budget than assuming daily use.

Choose your next step

Continue with the question that matches your next decision:

Sources & further reading

Numerical examples are illustrative unless explicitly described as measured. This guide does not claim hands-on product testing. Read the methodology and editorial disclosure.