Sous Vide Energy Use - 2012

One of the questions we often get asked is "How much energy does sous vide use"? We never knew the answer to this question so we decided to look into it. Energy consumption with sous vide is complicated because it differs greatly based on the device you are using, where in the sous vide process you are, and how much water you are heating.

To test several of these variables we purchased a P3 International P4400 Kill A Watt Electricity Usage Monitor and ran the sous vide machines we have through a series of benchmark tests.

The machines we used in our benchmarks are:
Sous Vide Professional Chef, one of the top of the line units for professional kitchens which retails for $800.

Sous Vide Supreme, one of the top of the line units for home kitchens which retails for $429.00

The SideKIC Immersion Circulator, an entry level immersion circulator for home cooks which retails for $170.

SousVideMagic, a sous vide temperature controller which retails for $159.00, hooked up to a 4 liter crock pot.

We had all of these units on hand and felt they represented a wide range of sous vide machines. We will also add more sous vide machines if we can get our hands on them. We ran many tests on these machines and the ones we will discuss specifically in this articles are:

• Median Watts Used While Heating with Sous Vide
• Kilowatt Hours Used to Heat Water with Sous Vide
• Median Watts Used While Cooking with Sous Vide
• Kilowatt Hours Used While Cooking with Sous Vide

We also just want to clarify that these tests were just done in my kitchen, not in a lab, and we're definitely not following stringent scientific protocol. However, we feel that these results accurately represent the performance of the various units and gives a good idea of how much electricity sous vide uses.

We also only had a crock pot big enough to hold 4 liters of water, so all the results for the SousVideMagic are based on 4 liters, not 10.

Median Watts Used While Heating with Sous Vide

We took 10 liters of water (4 liters for the SousVideMagic) at room temperature (about 70°F / 21°C) and heated it up to 131°F / 55°C. The machines were uncovered during the heating. While they were heating we took about 10 different samples of the watts being used by the sous vide machine. Below is a graph of the median watts used during the heating process.
Graph|type=bar&item_slugs=["sous-vide-professional","sous-vide-supreme","sidekic-immersion-circulator","sousvidemagic"]&item_type_field_keys=["avg_watts_heating_131"]&height=300px As you can see the Sous Vide Magic runs with the least amount of watts, closely followed by the SideKIC. The Sous Vide Supreme and the PolyScience circulator are at the other end of the spectrum and both use a lot more watts. Of course, at this point you are heating the water so generally the more watts used, the faster the water heats (this will be discussed in another benchmark testing article). But from a pure energy usage standpoint the SousVideMagic is the lowest.

Kilowatt Hours Used to Heat Water with Sous Vide

The second part of the watts used during heating is the total kilowatt hours used by the sous vide machine to heat the water to 131°F / 55°C. The total kilowatt hours used depends on the average wattage used, as well as the time it takes to heat the water.

A kilowatt hour is the typical unit that electric companies charge for. The cost of electricity varies greatly depending on where you live, even in the same country. Typically in America the rates range from a low of $0.05 to a high of $0.17 per kilowatt hour, in England it is about 12 pence. (if anyone else wants to send me the rates in your country I'll add it to this article.)

Here is the graph of the kilowatt hours used to heat the water.
Graph|type=bar&item_slugs=["sous-vide-professional","sous-vide-supreme","sidekic-immersion-circulator","sousvidemagic"]&item_type_field_keys=["energy_to_heat_131"]&height=300px The PolyScience circulator and Sous Vide Supreme have a shorter heating time which results in about 22% less kilowatt hours used than the the SideKIC. Of course, this only saves you about $.05 each time you heat your water. The SousVideMagic is the lowest, but if the volume of water was increased it would be more in the range of the SideKic.

Median Watts Used While Cooking with Sous Vide

Arguably the most important energy concern with sous vide cooking is how much energy is actually used during the cooking process. The 20 to 60 minutes it takes to bring the water up to temperature is nothing compared to the many hours (up to 48 or more) you can be cooking the food.

For the next two tests we brought our 10 liters of water to 131°F / 55°C (4 liters for the SousVideMagic). We then had them keep the water at temperature for about 10 hours. Every 30 to 60 minutes we would take the watts being used by the sous vide machine. The graph below shows the median watts being used. Graph|type=bar&item_slugs=["sous-vide-professional","sous-vide-supreme","sidekic-immersion-circulator","sousvidemagic"]&item_type_field_keys=["avg_watts_cooking_131"]&height=300px The PolyScience Sous Vide Professional uses the most average watts by far since the circulator is always running, the same is true of the SideKIC, it just has a weaker heating element. The SousVideMagic fluctuates between being on and off, so it has a high median value while the Sous Vide Supreme has a very constant but very low energy use.

Kilowatt Hours Used While Cooking with Sous Vide

During the time the sous vide machines were keeping the water at temperature we were monitoring their total kilowatt hours used. Here is a graph of their average kilowatt hours used every hour. Graph|type=bar&item_slugs=["sous-vide-professional","sous-vide-supreme","sidekic-immersion-circulator","sousvidemagic"]&item_type_field_keys=["kilowatts_at_131"]&height=300px The PolyScience and SideKIC used a comparable amount of kilowatt hours per hour due to their circulators running. The Sous Vide Supreme and SousVideMagic used about 60% less energy to keep the water the correct temperature.

At $0.10 per kilowatt hour it comes to about $0.005 per hour for the Sous Vide Supreme and SousVideMagic versus $0.012 per hour for the PolyScience and $0.013 for the SideKIC. While this is a big relative difference, it still comes out to less than a quarter a day in extra costs.

By way of comparison a typical microwave uses 1.44 kilowatt hours or about $0.14 an hour. A typical electric oven at 350°F / 175°C uses about 2 kilowatt hours or $0.20 per hour. Gas ovens seem to have similar costs of around $0.20 an hour as well. A slow cooker uses about 0.2 kilowatt hours or about $0.2 an hour.

So next time someone mentions the electricity costs of sous vide cooking let them know that cooking your chuck roast sous vide with a SousVideSupreme for 48 hours costs about $0.24 compared to $1.00 when using the oven for 5 hours!

Purchase Any of These Machines

Sous Vide Professional Chef, one of the top of the line units for professional kitchens which retails for $800.

Sous Vide Supreme, one of the top of the line units for home kitchens which retails for $429.00

The SideKIC Immersion Circulator, an entry level immersion circulator for home cooks which retails for $170.

SousVideMagic, a sous vide temperature controller which retails for $159.00, hooked up to a 4 liter crock pot.

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This article is by me, Jason Logsdon. I'm an adventurous home cook and professional blogger who loves to try new things, especially when it comes to cooking. I've explored everything from sous vide and whipping siphons to pressure cookers and blow torches; created foams, gels and spheres; made barrel aged cocktails and brewed beer. I have also written 10 cookbooks on modernist cooking and sous vide and I run the AmazingFoodMadeEasy.com website.

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