How Much Energy Does Sous Vide Use? The Sous Vide Power Consumption Benchmark

On this website, as well as other places online such as the sous vide subreddit, there are often questions regarding the power consumption of sous vide cooking. Questions like the following:

• How much power is used for a typical sous vide cook?
• How much impact does the water bath insulation have on sous vide power usage?
• How do water ovens compare to sous vide immersion circulators on power usage?
• Is sous vide power usage something that we really need to be concerned about?

Motivated by this and our own curiosity, we decided to define and run a Sous Vide Power Consumption Benchmark to gather some empirical data on this interesting topic. Hopefully, this article will answer some of the questions you have regarding power usage during sous vide cooking.

Table of Contents

• Overview of the Sous Vide Power Consumption Benchmark
• Sous Vide Power Consumption Benchmark Testing Configurations
• Sous Vide Power Consumption Benchmark Measuring Instruments
• Sous Vide Power Consumption Benchmark Data
• Sous Vide Power Consumption Benchmark Results

Overview of the Sous Vide Power Consumption Benchmark

The idea was for the power consumption benchmark to model a typical one day sous vide cook. The sous vide machine was filled with water at a room temperature of 75°F (23.89°C). The target temperature was set to 140°F (60°C). This is a temperature that would normally be used for cooking something like chicken, pork, or a medium steak.

Once the target temperature is reached it is maintained for the remaining portion of the cook. The temperature is tracked during this time to determine any variation.

The benchmark runs for 24 hours during which time the temperature is recorded as well as the power usage at the end of 1 hour, 12 hours, and 24 hours. I ran the benchmark on four different configurations of an immersion circulator and two different water ovens.

This post is quite lengthy since I felt it was important to describe in detail how the Sous Vide Power Consumption Benchmark was created and executed. However, if you are just interested in the results of the benchmark you can link directly to the Sous Vide Power Consumption Benchmark Results section at the end of this post.

I will admit up front that this Power Consumption Benchmark does not have the rigor suitable for a scientific journal. However, I did try to make it as fair and repeatable as possible given the amount of time and expense I was willing to invest. So please keep in mind that small differences between the performance of the various machines and configurations being benchmarked may, or may not, be statistically significant.

Sous Vide Power Consumption Benchmark Testing Configurations

All configurations started with 10 liters of water at a room temperature of 75°F (23.89°C). In each case the target temperature was set to 140°F (60°C).

The configurations with an immersion circulator used the Anova One. I am also using my Camwear Polycarbonate Square Food Storage Container as the water bath container.

All sous vide machine configurations ran for 24 hours with measurements taken along the way.

Immersion Circulator with Open Water Bath

This configuration was the easiest to set up since it was simply the Anova One immersion circulator in the water bath containing 10 liters of water. The temperature probe wire was attached to the side of the water container with the probe submerged in the bath.

It was clear from watching this particular configuration that it is not one that you would want to use for a sous vide cook longer than an hour or so. Even at the relatively low temperature of 140°F (60°C) you could see the steam rising from the bath carrying off both heat and water.

In fact, it carried off so much water that I could not complete the full 24 hour test. This is because when I took the power reading after 12 hours the water level had already gone down more than 2" (5.08 cm). That left only 0.75" (2 cm) before the water level would drop below the Minimum level required by the circulator. Since this would have occurred in the middle of the night, and I preferred not to test the automatic shut off on my Anova, I chose to terminate the test at that point. I then did a few calculations to extrapolate what I felt the power consumption would've been at 24 hours.

Immersion Circulator with a Lid on the Water Bath

In this configuration I added a tight-sealing lid to the water container to keep in the heat and moisture. This is the lid I typically use in which I cut a "U-shaped" opening for the Anova One immersion circulator. I ran the wire for the temperature probe through this opening as well and had the probe submerged in the bath.

As you would suspect, this lid helped to reduce both the energy consumption and the loss of water in the bath. And since both the water container and the lid are clear you can "keep an eye on" how the sous vide cook is progressing, something I prefer for peace of mind.

Immersion Circulator with a Lid on the Water Bath, Then Insulated

For this configuration I took the additional step of insulating the lidded water container used in the previous configuration. This was performed by wrapping the water bath in approximately four layers of bath towels.

Although this is more energy efficient, I wasn't wild about it because I couldn't easily keep track of what was going on with my cook. For example, if a sous vide bag were to spring a leak or float to the surface, it could be a real mess after cooking for a day or two.

Immersion Circulator in a Cooler Water Bath

For this configuration I used the 16-Quart Coleman Excursion Cooler. I found the dimensions of this cooler to be a good size for a sous vide bath with internal dimensions of 12.5 x 9 .7 x 8.2" (31.7 x 24.6 x 20.8 cm). Also the Thermo Zone insulation contains no CFCs, HFCs, or HCFCs.

First, I used a screwdriver to pry the lid off of the cooler and then cut off the two small plastic "hinge pins" that were used to hinge the lid to the cooler. Next I cut a "U-shaped" hole out of the lid to make room for the immersion circulator. Obviously, this needs to be done but there is a downside. By cutting into the lid the insulating properties of the lid are diminished since you have essentially eliminated the airspace. The lid fits quite securely even without the hinge pins in place.

While running the power consumption benchmark I did notice that there was not a lot of heat being lost through the sides of the cooler. However, the top was quite warm and I assume that's where the majority of the heat loss occurred.

Sous Vide Supreme Water Oven

In this configuration I used the best known water oven in the industry, the Sous Vide Supreme. To this I added the 10 liters of water and slipped the temperature probe wire under the lid so that the probe was immersed in the water bath.

While running this test with the Sous Vide Supreme I noticed that the sides of the device were only slightly warm since they are fairly well insulated. However, the lid is not insulated and therefore is quite hot to the touch. They have the black pad that sits on top which helps to insulate the majority of it, but I suspect the top is still responsible for the majority of the heat loss for this unit.

Oliso Water Oven

This unique sous vide machine is comprised of two parts; the Oliso PRO SmartHub and the removable Precision SmartTop. The SmartHub is an advanced induction cooktop intended for easy yet powerful control over cooking processes. The Precision SmartTop is a removable, large capacity water bath designed to hold liquid at exact temperature for long periods of time making it suitable for sous vide cooking as well as other applications.

For this configuration I added 10 liters of water and slipped the temperature probe wire under the lid so that the probe was immersed in the water bath.

Sous Vide Power Consumption Benchmark Measuring Instruments

I use two different instruments to take measurements during the Sous Vide Power Consumption Benchmark. They are described in the paragraphs below.

Temperature and Humidity Data Logger

For monitoring the temperature I use the Inkbird THC-4 LCD Display USB Temperature and Humidity Data Logger. This unit was relatively inexpensive and full-featured including:

• Optional external temperature sensor (which is what I use)
• Temperature measuring range on the remote sensor of: -30°C - 85°C (-22°F - 185°F)
• Temperature accuracy: 1.0°C
• Temperature resolution: ± 0.1°C
• Record capability: 16,000 points
• Record interval: 10 seconds - 24 hours
• Communications interface: USB

The data logger comes with data management software which you can load on your PC. This software allows you to adjust the various parameters in the data logger such as the record interval, time and date, calibration values and temperature units (°F or °C). It also allows you to view the data collected numerically as well as various graphical forms. In addition you can download the data to a variety of file types including Excel.

Electric Usage Monitor

For monitoring the power usage I use the P3 P4400 Kill A Watt Electricity Usage Monitor. This unit can measure numerous electrical parameters associated with the device which is plugged into it. For the Sous Vide Power Consumption Benchmark I only use it to record the overall power consumed by the unit being benchmarked in kilowatt hours (kWh).

I took three kWh measurements during the execution of the benchmark. The first one after the first hour, the second after 12 hours, and the third after 24 hours, i.e. at the end of the benchmark.

Sous Vide Power Consumption Benchmark Data

For each sous vide power consumption configuration I ran the benchmark on, I report on 14 data points, which are either measurements or calculations. Each of these is described briefly below.

Room Temperature Startup Time (Minutes)

During the first hour of the benchmark the water bath is heated from room temperature of 75°F (23.89°C) to a target temperature of 140°F (60°C). This is a temperature typically used for cooking things like chicken, pork, or medium steaks. The time to reach this temperature is referred to as the "Room Temperature Startup Time" (See graph above).

Hot Tap Startup Time (Minutes)

Often when starting a sous vide cook you may be filling the bath direct from the hot water tap. This water is normally around 125°F (51.67°C). The time required to get the water bath from this temperature up to the target temperature is referred to as the "Hot Tap Startup Time" and is obviously shorter than the "Room Temperature Startup Time" (See graph above).

Water Temperature (°F)

During the entire benchmark the sous vide machine target temperature is set to 140°F (60°C). This data point indicates the temperature recorded on the temperature logger for the water temperature. Often this temperature varies slightly from the 140°F target temperature.

This does not necessarily mean that the sous vide machine is maintaining an incorrect temperature. The temperature sensor in the sous vide machine might actually be more accurate than my temperature logger. Also, the temperature in the water bath may be slightly different depending on where the temperature is measured.

Water Temperature Maximum (°F)

Once the target temperature has been reached the water temperature is tracked for the remaining portion of the benchmark. This data point indicates the highest water temperature recorded during the entire cook.

Water Temperature Minimum (°F)

Once the target temperature has been reached the water temperature is tracked for the remaining portion of the benchmark. This data point indicates the lowest water temperature recorded during the entire cook.

Water Temperature Variation (°F)

Once the target temperature has been reached the water temperature is tracked for the remaining portion of the benchmark. This data point indicates the variation in water temperature during the entire 24 hour cook. It is simply calculated by subtracting the Water Temperature Minimum from the Water Temperature Maximum.

First Hour Benchmark Power Consumption (kWh)

At the conclusion of the sous vide power consumption benchmark's first hour the power consumption (kWh) is recorded.

12 Hour Benchmark Power Consumption (kWh)

After 12 hours the power consumption (kWh) is recorded.

24 Hour Benchmark Power Consumption (kWh)

After 24 hours the total power consumption (kWh) is recorded.

Average Power Used During Cook (Watts)

The average power used during the cook can be easily calculated by dividing the 24 Hour Benchmark Power Consumption (kWh) by the 24 hours and multiplying by 1,000. I believe this number is useful because we can compare it to other devices whose power we are familiar with such as a 100 W light bulb or a 1200 W microwave oven.

Approximate Water Level Drop (Inches)

At the end of the 24-hour-long benchmark I measured the approximate amount the water level in the water bath container had dropped due to evaporation.

Total Cost for 12 Hour Cook @ $0.15/kWh ($)

This is what it costs to run the sous vide machine for a 12 hour cook. It is a simple calculation using the 12 Hour Benchmark Power Consumption above multiplied times a cost per kilowatt hour of $0.15. Keep in mind that the cost of electricity varies greatly throughout the country ($0.10 to $0.50/kWh). You will have to find your cost per kWh from your utility statement in order to calculate what it would cost you.

Total Cost for 24 Hour Cook @ $0.15/kWh ($)

This is what it costs to run the sous vide machine for a 24 hour cook. It is a simple calculation using the 24 Hour Benchmark Power Consumption above multiplied times a cost per kilowatt hour of $0.15. Keep in mind that the cost of electricity varies greatly throughout the country ($0.10 to $0.50/kWh). You will have to find your cost per kWh from your utility statement in order to calculate what it would cost you.

Total Cost for 72 Hour Cook @ $0.15/kWh ($)

This is an estimate of how much it costs to run the sous vide machine for a 72 hour cook. It is three times the cost of the 24 hour cook.

Sous Vide Power Consumption Benchmark Results

I ran the sous vide power consumption benchmark on six different sous vide machine configurations; four using an immersion circulator and two using a water oven. The table below summarizes the results of these tests.

Note: For an up-to-date look at the results of our latest tests, including numbers for specific sous vide machines, you can read our sous vide benchmark results article.

There are a number of conclusions/observations that can be drawn from this summary table.

Room Temperature Startup Time

The startup time of all units were close to 30 minutes. Since I was using the Anova One for all of the immersion circulator configurations, you can see clearly the difference, albeit relatively small, made by the insulation capabilities of the water bath container. The better insulated the container, the less time required to reach the target temperature.

Interestingly, one of the water ovens took the most time to reach the target temperature while the Oliso achieved the target temperature the fastest of all the benchmark configurations.

Water Temperature Variation

The Anova One kept a very consistent target temperature throughout the duration of the cook in all four of the benchmark configurations. The two water ovens had more variation with the Oliso being the worst with a variation of nearly 2°F.

First Hour Power Consumption

Approximately half of the first hour of cook time was bringing the water up to the target temperature. It is also no surprise that for the circulator configurations, the more insulated the container was the less power it took to reach the target temperature.

Both of the water ovens were able to achieve the target temperature using slightly less power than the configurations with the immersion circulator. This may be due to the fact that the water ovens do not use a pump to circulate the water, which would require additional power to operate.

24 Hour Benchmark Power Consumption and Average Power Used During the Cook

Similar to the First Hour Power Consumption above, the amount of power consumed during the entire benchmark depends primarily on the amount of insulation surrounding the water bath container. Running a sous vide water bath without any cover at all does not seem to be a prudent thing to do unless it's a very short cook since you are both wasting power and risking that the cook may be aborted without your knowledge due to a lack of water in the bath.

The Oliso water oven was the most stingy when it came to power consumption. It used less than a third as much power as the Anova One immersion circulator in a bath with just a lid. Unfortunately that unit also had the greatest variation in the target temperature as well as the highest price.

Cost Analysis of Sous Vide Cooking

Before reading this post you may have been somewhat unfamiliar with the parameter kilowatt hours (kWh), it is not something that we use often in our daily conversation. Most of us are much more familiar with the term "Watts", since it is an important and well understood parameter in things such as light bulbs, audio video components, microwave ovens, and of course, immersion circulators.

But the one parameter I know we can all relate to is "dollars", so I want to conclude this article discussing what we can all easily understand.

For this reason I have converted the amount of power consumed for each of the configurations of the power consumption benchmark into what that particular cook would have cost. For this I used in average cost per kWh of $0.15. Keep in mind that the cost of electricity varies greatly throughout the country ($0.10 to $0.50/kWh). You will have to find your cost per kWh from your utility statement in order to calculate what it would cost you.

From reviewing the estimated "Total Cost for a 72 Hour Cook" row in the table you can see that, ignoring the "Open" configuration, the cost is less than $2.00, in fact in most cases, less than $1.00. Even on a long cook like this, the difference between the most power efficient and least efficient configuration is only about $1.18. So obviously we are not talking high finance here! Especially considering that the average US household uses around 1,000 kWh per month at a cost of about $150.

I could be wrong but I suspect that most home cooks who are willing to put out $200 or more for a sous vide machine, which they use sporadically, are probably not going to be too concerned with the small difference in operating costs of the various configurations. I would think there are other factors that they may consider more important as they make their purchasing decision for a particular sous vide machine.

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This article is by Gary Logsdon, my resident equipment tester, researcher, business partner, and most importantly, my Dad. He loves diving into the nuts and bolts of different pieces of equipment, researching what works best, and sharing that information with you.

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