Refrigeration In a Van (and Keeping Insulin Cold)

keep insulin cold in a car

I generally do not use refrigeration in my minivan camper, but I understand why someone might want to.  It’s nice to have the option of a cold beverage of course, but I was recently asked a more compelling question; how do I keep insulin cold when camping?

Needing to keep your insulin from getting too hot when out on the road is a very compelling reason to have refrigeration in your vehicle and I wanted to address it.  However, everything here also applies if you just want to keep food and drinks cold.  If you don’t need to worry about anything more, scroll down and watch the videos.  This post has a “Part 1” and “Part 2” video, which are linked below.

Traveling with Insulin

I’m not a diabetic (yet, knock on wood) so I had to do some online research to understand the requirements of storing insulin.  After looking at 6-8 sources, I found one that was pretty complete and which seems to be accurate when compared to other available data.  Here’s a link to their insulin fact sheet.

A couple of insulin facts that I pulled off the site are:

  1. Insulin you are storing and not currently using should be kept between 36 degrees and 46 degrees Fahrenheit. If it gets colder than that it can freeze. If it gets warmer than that, it will be good for a while, but eventually, it will start to break down and become less effective.
  2. The standard recommendation from all the insulin manufacturers is that a vial of insulin you are using can be kept at room temperature for up to 28 days. Room temperature is defined as between 59 degrees and 86 degrees Fahrenheit. This works because all the standard insulin preparations have preservatives in them — which will keep the insulin good for a while but eventually stop working. After that, Bacteria begin to grow in the insulin and start breaking down the protein.
Keeping Insulin Cold
Insulin is a protein and needs to be treated similarly to other proteins.

 

 

 

 

 

 

 

 

Looking at these guidelines, there are two reasons for refrigerating insulin.

a) If you are storing more than a 28 day supply

b) If it might get over 86 degrees…..like it would in pretty much ANY vehicle left in the sun.

It is worth mentioning that when insulin goes “bad” it does not become toxic.  Rather, it loses it’s effectiveness and really, that’s almost as bad.


Two Options for Minivan Refrigeration

Using the guidelines for temperature, I came up with two ways that you can protect your insulin supply, or just keep a beer cold.   Since this blog is all encouraging people to travel, I wouldn’t want to see anyone limited by their medications.  Both solutions will provide cold storage in a vehicle, for as long as you want to stay out, assuming you have gas and water.  The first solution is only $100.  The second is $200 but gives you more options.  I wanted these solutions to be economical and take up a minimum of space.  They also had to be efficient enough to run effectively off of solar and a house battery system.  In a pinch, either one should be able to run off of the vehicle battery, even if the vehicle has to be running.  You can find links to each at the end of this article.

  • Part 1

Here’s where this post turns into a video.  Two actually.  Some things are better conveyed in writing and others in video.  I try to blend the two where appropriate.  So, watch the video and then come back for the rest of the post.  Part 1 covers making ice while traveling full time and Part 2 covers a portable refrigerator–freezer–cooler unit.

Oh, and while you are over on YouTube, click on the “bell” so you get notifications of new videos.  Part 2 is coming and I wouldn’t want you to miss it.

 

  • Part 2

This solution involves a cooler with a built-in compressor refrigerator from Alpicool, who makes 12V units for in-vehicle use.  NOTE: this unit has an automatic shutoff to protect your battery from running down.  I did not use it in my test because I wanted to see the runtime without the limit imposed.  I chose the C15 as a good compromise between size, efficiency, and cost.  It’s an awesome solution for cooling your insulin, or just having a cold beer when you are boondocking. Watch the video and then come back here, because I have lots of info below.

 


I will state up front that I do not like to use “dorm” style refrigerators in a minivan.  The footprint is usually large enough that you can’t find a level spot to place one, without some additional mods.  They are also high in profile, which means you can’t tuck one under a bed.  You can make them work and that’s fine if you want to, but I think the cooler style refrigerators are a better idea.  These dorm fridges do not seem to be very well insulated, the ones under $300 will not run off of 12V, and all the cold air spills out when you open the door.  Of course, you COULD by an RV style “Dometic” or another brand of 12v fridge, but they tend to be more expensive and you still lose the cold air when you open the door.


On the cooler-style refrigerators, the cold stays inside when you open the top and settles to the bottom where the food actually is. They are also portable.  Unplug it and bring it over to the picnic table.  It’s still a cooler, even when it’s not plugged in!  You can even put ice in them, in a pinch.

The Alpicool C15 refrigerator cooler uses up to 60 Watts when running.  On a 12 Volt system, that means it can draw 5 Amps (60W/12V=5A).  In one hour, it would use 5 Amp Hours (Ah) of your battery reserve.  However, the compressor only runs about 50% of the time.  So that means you are using about 2.5A per hour.  My starter battery in the Odyssey is 44Ah (I THINK).  I never want to draw it down more than 50%, so theoretically, that would give me 8.8 hours of runtime without starting the van to charge the battery.  I wanted to err on the side of caution and used 6 hours as a reasonable amount of time that you would run off of the starter battery without starting the car.  That’s probably close to how long you would be away from the vehicle or asleep.  However, as you will see in the video, I was able to run the cooler/refrigerator off of the vehicle battery for only 3 hours in a real-world test.  The Alpicool worked flawlessly and drew the exact amount of current that I was expecting, so something else must be to blame.  I’ve narrowed in down to one of three possibilities:

  1. My battery is not as large as I thought, or (just as likely) it’s five years old and on its way out.
  2. The compressor ran more than anticipated due to it being 80 degrees out and the van being parked in the sun (still, it doesn’t fully explain the limited run time).
  3. I’ve overlooked something else.

Based on my test in the video, I can’t suggest running this solely off the starter battery without running the vehicle.  However, if you are working up to a battery system, I would plug in when you are driving and then let it run off the battery for an hour or two before bed.  If you pack it full, the thermal mass should keep things cool until morning.

If you have a house battery system or solar generator, you could run the Alpina fairly easily.  A 100W panel could run it during the day and if you keep the cooler full, it would probably stay cold all night, using 25Ah in ten hours of use.  If you want to “coast” for the last couple of hours of darkness, you could use a timer switch to shut it off until sunrise.

Well, that’s what I was able to learn by testing these systems for a couple weeks and then shooting video all weekend.  I’m now going to focus on the rebuild of my bed system (I was not satisfied with the first attempt) and getting back out in late September or early October.

Remember, if you use the links below, it won’t cost you a penny more, but a portion of the sale will go to keep the site running and to our giveaways.

All items featured in this post are on my KIT page:

As always, thanks for reading and watching the videos!  That’s what makes me want to do more!  For a complete list of my DIY minivan camper conversion projects, click on the menu item at the top.

–Darren

Odyssey Camper


Storing insulin in your car

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