Slow Cookers provide the freedom to cook meals while focusing on other daily tasks, but how much electricity does a slow cooker use and how does this compare to other appliances such as an electric stove or oven?
When run for 8 hours on the low setting, a typical slow cooker will consume about 1.44 kW/hours of electricity. There are several variables that affect the overall power consumption of a slow cooker. But generally, a slow cooker is an energy-efficient alternative to an electric stove or oven.
There are 4 areas we will explore further to answer how energy efficient using a slow cooker can be and how much they cost to run (compared to a stove/oven).
- How much electricity does a slow cooker use?
- How much does it cost to run a slow cooker?
- Are slow cookers energy efficient?
- Is it cheaper to use a slow cooker or a stove/oven?
Before we get into it, as a general safety note, always be sure to follow suggested recipe settings and adhere to the safety instructions of your specific slow-cooker.
How Much Electricity Does a Slow Cooker Use?
Calculating the electricity use of a slow cooker depends on several variables including temperature setting (low of high), duration of cooking, and the size of your slow cooker.
Let’s start with a quick overview of how power consumption is measured, then we’ll do the math for a slow cooker example.
How Power Consumption is Measured
For most homeowners and renters, the important number for power consumption is going to be kilowatt/hours (kWh).
This is the number that your electric provider will use when it comes time for billing and is a result of two other factors, amperage (current) and voltage (electrical “pressure”).
Let’s briefly define these terms for clarity:
- Amperage (A) – The current in an electrical circuit. This considers both the volume and flow-rate of the electricity.
- Voltage (V) – The potential electrical difference between points of an electrical circuit. This is essentially the underlying “push” that moves electricity in a circuit
- Wattage (W) – The Power (P) output in an electrical circuit that results from both amperage and voltage.
Note: Resistance also plays a factor in electrical systems but we can afford to overlook this for the sake of our slow cooker investigation.
A common way to think about this, is thinking about electricity as if it was water in a garden hose. Amperage would describe the flow-rate of a certain volume of water through the hose and Voltage would describe the pressure exerted by the water.
When multiplied together, we get the Wattage (power) that the water generates. If we increase the pressure or current coming from the hose, we see a higher resulting power output.
The Math (and an Example)
Now we’ll walk through the math using the low-cook estimate for a slow cooker.
Slow cookers operate using a standard 120V outlet. They also operate at a fairly low amperage, about 0.6 amps when keeping food warm to 2 amps when operating in a high cooking mode.
In order to figure out the Power output, we simply multiply the Amperage and Voltage together using this equation.
Amperage x Voltage = Power (Watts)
We will assume the slow cooker is in the low-cook mode, which draws about 1.5 amps
Step 1: 1.5 Amp x 120Volts = 180W
A meter reading is done in kilowatts. 1 kilowatt is equal to 1000 watts in the same way that 1 kilometer is 1000 meters. To have our output be in kilowatts, we must divide the product of the above equation by 1000 watts (1 kilowatt)
Step 2: 180 W / 1000 W = .18 kW
To get this amount into kilowatt hours, we then must multiply the product in example two by the time that we were consuming the electricity. Let’s say, for example, 8 hours.
Step 3: 0.18 kW x 8 hours = 1.44kW/hours
So we see that using a slow cooker on a low-cook setting for about 8 hours will use about 1.44 kWh of electricity.
Now, let us take a look at how this translates into cost…
How Much Does it Cost to Run a Slow Cooker?
At the time of writing this article, the average residential cost for electricity in the United Sates is hovering around $0.13 per kWh. This would put the cost of our hypothetical power consumption at the following.
Step 4: 1.44 kWh x $0.13 = $0.19
So, we can see that running a slow cooker for 8 hours on the low setting, would cost about $0.19.
We can follow the same steps to calculate that using a slow cooker on a high-cook setting for 8 hours would cost about $0.25 on average.
However, using a high-cook setting would cut down on the time needed for cooking. So, if we only cooked for 5 hours on high, then the cost is essentially the same, at about $0.19.
On paper, the cost efficiency between a high and low setting switches (high becoming more expensive) if the high setting is used for more than 60% of the low-setting cook time.
Of course, there are many variables that can affect this math, including the size of your slow cooker and even the type of food being prepared. It is usually best to simply follow whatever the recipe calls for.
Are Slow Cookers Energy Efficient?
As we saw above, slow cookers use a relatively low amount of power. This makes them a great alternative to stove-top and oven cooking.
One of the great benefits of the slow cooker is that much of its energy is conserved. Little heat is lost to ambient surroundings. In comparison, a stove-top burner may heat/cook the food quickly, but it also loses a lot of energy to the air and other elements of the stove.
Some slow cookers, as well as many ovens, can also operate with what is known as a “duty cycle” in order to help conserve energy use. This functions in the same way that a furnace connects to a thermostat.
The heating element will periodically turn off and back on to maintain a constant temperature. The appliance, then, isn’t constantly drawing energy the whole time that it is on.
Is it Cheaper to Use a Slow Cooker or Stove / Oven?
Calculating the cost of running a stove uses the exact same method that we would use for a slow cooker. The main difference is that the amperage and voltage of a stove or oven is going to be drastically higher than a slow cooker.
The cooking time, however, is generally less when using a stove or oven. So what kind of numbers does this yield?
A residential electric stove/oven, on average, functions using a 220 V outlet and can draw between 30 and 50 amps. Much larger numbers than our slow-cookers.
Using our equations from earlier, we see that a stove drawing 30 amps would use 6.6 kWH if used continuously for one hour. This would cost about $0.88 per hour.
However, stove-top cooking time is usually less than a full hour. If we assume we use a burner for only 20 minutes, the total cost of that particular cooking time would be $0.29.
Using an oven also requires a higher electrical draw. The main variable to consider with an oven is that the primary electrical draw is during its heating cycle.
While the oven is heating to the desired temperature, it will be using a considerably larger amount of energy than after it reaches that temperature and the heating unit shuts off.
This makes the power consumption of an oven less than what it would be simply doing the hypothetical math. To have a completely accurate calculation of the energy use of an oven, you would need to track the cumulative time that the heating element is functioning, not just simply the cook time.
Overall, the slow cooker is going to be more cost-efficient than using an electric stove-top or oven. The trade-off for using the stove-top or oven is going to be in the much shorter cook times compared to using a slow cooker.
What Temperature Does a Slow Cooker Cook At?
Slow cookers will generally heat up to about 190-210 degrees Fahrenheit (~87-99 degrees Celsius) on the Low setting and can go up to about 300 degrees Fahrenheit (~149 degrees Celsius) on the High setting. However, slow cooker temperatures will vary based on cook time, brand, model, etc.
Do Slow Cookers Need Water?
You only need to add water to a crock pot, if the meal or recipe you’re slow cooking requires it. Some meals, like a ham, do not require any liquid to be added. Other recipes, like slow cooker bread or soup, do require water. And finally, some recipes will require added liquid (like broth), but not water.