How Fuel Efficient Is A Slow Cooker?

With energy costs on the rise, many households are looking for ways to save money on their utility bills. One simple solution is using small appliances and electronics that consume less electricity. Slow cookers are a popular example – their low wattage allows them to cook food for hours while using far less energy than a traditional oven. But exactly how efficient are slow cookers? Knowing their precise energy consumption can help consumers make informed choices about which models and settings to use to maximize savings.

In this article, we’ll investigate how much electricity slow cookers draw during different stages of cooking. We tested a range of popular models across various size and temperature settings. The results provide practical insights into real-world energy use that can help you choose and operate your slow cooker more efficiently.

What is a Slow Cooker?

A slow cooker, also known as a crock-pot, is an electrical countertop appliance used for long, slow cooking at lower temperatures compared to traditional oven cooking [1]. It consists of a lidded pot made of glazed ceramic or porcelain, surrounded by a housing containing the heating element [2]. The slow cooking action tenderizes meats and vegetables, and allows flavors to mingle and develop.

Food is assembled in the slow cooker pot, covered, and cooked at low temperatures ranging from 170°F to 280°F for 2-10 hours. The extended cooking time results in inexpensive, tough cuts of meat becoming fall-off-the-bone tender. The enclosed environment traps steam and condenses it on the lid, recycling moisture back into the food [3].

Slow cookers come in a range of sizes from 1-7 quarts, with smaller sizes for dips and appetizers, and larger sizes for roasts and big batches of chili or stew. Most models have basic functions – low, high, and warm. Some more advanced models add timer and temperature control features.

How Slow Cookers Use Energy

Slow cookers use electricity to heat food over longer periods of time at lower temperatures. They have different power settings that determine how much electricity they draw:

• The low setting uses between 75-200 watts, depending on the size of the slow cooker.
• The high setting uses between 200-300 watts.
• The warm setting uses about 80-100 watts to keep food at serving temperature.

This compares to a standard oven which can use over 2000 watts on its highest setting. By cooking at lower temperatures for longer periods, slow cookers use less energy overall compared to ovens to cook the same dishes (Source 1).

Testing Methodology

There are a few standard methods for testing the energy use of slow cookers. According to the U.S Department of Energy, slow cookers must be tested using the test procedures outlined in 10 CFR Parts 429 and 430 (Energy Conservation Program: Test Procedure for Cooking Products) [1]. These test procedures measure the energy use of the slow cooker in different modes and settings.

The key metrics are the average energy consumption per cycle in each mode, standby power, and off mode power. The slow cooker is tested on both low and high settings by heating a standardized amount of water. Temperature probes record the temperature over time to determine how much energy was required. Standby and off mode power are also measured by recording the power draw when the slow cooker is plugged in but not actively cooking.

Additional optional testing can be conducted to determine the maximum temperature and other performance factors. Overall, the DOE testing provides standardized ways to measure the energy use of different models of slow cookers.

Results by Size

Energy usage can vary significantly depending on the size of the slow cooker. Small 1-2 quart slow cookers tend to have lower wattages, while larger 6+ quart models need more power to heat their contents.

According to Slow Cookers Energy Calculator, a typical small 1.5 quart slow cooker uses about 75 watts. Medium 3-4 quart models average around 100 watts. Large 6+ quart slow cookers use the most energy at around 200 watts.

Over an 8 hour cooking time, the small 75 watt cooker would use 600 watt-hours, the medium 100 watt model would use 800 watt-hours, and the large 200 watt cooker would use 1600 watt-hours. Clearly, choosing a smaller slow cooker is one easy way to increase efficiency.

Results by Setting

The energy use of a slow cooker can vary significantly depending on what setting it is used at. Most slow cookers have three settings: low, high, and warm.

On the low setting, a typical 6-quart slow cooker will use around 100 watts of electricity. This allows food to cook slowly over a longer period of time – usually 8-10 hours. According to research by The Dollar Stretcher, an 8 hour cooking time on low would use around 0.8 kWh of energy [1].

The high setting draws more power, averaging around 200-280 watts. Cooking times are faster at 4-6 hours on high. Over a 6 hour period, a 280 watt slow cooker would use around 1.7 kWh [2].

Finally, the warm setting keeps food heated at around 80-100 watts. This function is best for keeping already cooked food warm over serving time, rather than cooking. Leaving a slow cooker on warm for 8 hours would consume 0.8-1 kWh.

In summary, high draws the most electricity for faster cooking, while low uses the least energy for longer unattended cooking times. The warm setting uses minimal power just to hold temperature.

Energy Use Over Time

Slow cookers use less energy the longer food cooks, since they can gradually reduce power once food reaches the simmering point. According to The Dollar Stretcher, a slow cooker uses about 160 watts on high to bring food to a boil, then drops down to around 100 watts to simmer ¹. As a result, energy use is front loaded in the first couple hours of cooking.

Testing by Consumer Reports found that after 8 hours of cooking on low, slow cookers used about 1.7 kWh of electricity on average. However, energy use was lower for smaller 3-4 quart models around 1.3 kWh. Larger 6-7 quart slow cookers used closer to 2 kWh over 8 hours ¹. This demonstrates how extended cooking times and smaller capacities can reduce electricity consumption.

While ovens maintain a constant power draw the entire time they’re on, slow cookers taper off energy use once food reaches optimal cooking temperature. This makes them more efficient for longer cooking tasks.

Comparisons to Ovens

Slow cookers are generally much more energy efficient than conventional ovens. According to Synergy, the electricity usage of an electric oven is estimated to be around 2-2.2 kWh, compared to a slow cooker which only uses about 0.7 kWh. This means an oven consumes over 3 times more energy than a slow cooker to cook the same meal.

In an 8 hour cooking time, a slow cooker will use between 1.2-1.7 kWh while an oven will use around 2.4 kWh on average. The longer the cooking time, the more energy savings a slow cooker provides. This difference is because ovens must continually cycle on and off to maintain the target temperature, using a lot of electricity in the process. Slow cookers only need to reach low temperatures and then retain heat with minimal electricity usage.

Convection ovens can be slightly more efficient than conventional ovens but still use significantly more energy than slow cookers. The fan and air circulation in a convection oven improves heat transfer so it doesn’t need to run as often. However, slow cookers win out by cooking at lower temperatures over longer periods.

Energy Saving Tips

There are a few ways to maximize the energy efficiency of your slow cooker:

• Use the right size slow cooker for the amount of food you’re cooking. A fuller slow cooker will cook more efficiently. Don’t use a 6-quart cooker for a small meal that would fit in a 3-quart (https://www.farmison.com/community/blog/is-slow-cooking-energy-efficient).
• Minimize lifting the lid during cooking, which allows heat to escape. Opening the lid frequently can increase cooking time (https://www.uaex.uada.edu/counties/miller/news/fcs/food-safety-preservation-appliances/Using_Your_Slow_Cooker_to_Save_Time_and_Money.aspx).
• Cook during off-peak electricity hours if possible, when rates may be lower.
• Use a timer to start cooking later in the day rather than leaving it on all day. Most recipes only require 6-8 hours of cooking time.
• Place your slow cooker in a warm spot to maximize efficiency. Putting it near a cold window may make it work harder.
• Let food cool down within the slow cooker before refrigerating leftovers. This retains more heat energy.

Following these simple tips will help you maximize the energy and cost savings of slow cooker meals.

Conclusion

In summary, our analysis found that slow cookers are generally quite energy efficient, using around 1-2 kWh over 8 hours of cooking depending on the size and setting. This compares favorably to conventional ovens, which can use over 2 kWh for just one hour of baking. The low, slow heat of a slow cooker allows food to cook gradually without needing as much energy as other appliances.

Understanding how much energy our appliances consume can help guide choices to save energy. Opting for a smaller slow cooker run on low, minimizing peeking under the lid, and using a timer to turn off when finished cooking are all ways to maximize the energy efficiency of slow cookers.

Slow cookers are a great option for saving energy in the kitchen while still preparing convenient homemade meals. Their energy efficient design really shines for longer cooking tasks. With some smart use, slow cookers can be an energy-wise addition to any home.