build an energy efficient camper fridge

Campers & RVers: Do you know how much of your valuable energy reserves are being consumed by your refrigerator?

Even if you happen to have a very efficient refrigerator, chances are that you are draining tons more than you really need to be.

Consider these questions:

  • Is your refrigerator running most of the day?

Especially if you're in a hot climate, it's probably running almost full time. Assuming you turn off the lights at night, and use the AC/Heating only when you need it, your refrigerator is the most energy consuming appliance in your RV, because it's intermittently consuming energy 24/7.

Camping Refrigerator

Wastefully Empty Refrigerator

  • Is your refrigerator packed completely full most of the time or is it half empty most of the time?

If you're like a lot campers, you fill your fridge with what you need when you leave and gradually empty it out until you're back in civilization to restock, when you'll find it either completely empty or half full of stuff you never touched. In other words, you're probably cooling tons more air than is really necessary.

  • Is your refrigerator front-opening or top-opening?

Duh. Of course your refrigerator is probably front opening like every other manufactured refrigerator. And like every other refrigerator, you dump out all that cold air every time you open the door. What a humongous waste!

Non Energy Efficient Refrigerator

Familiar family photo of cold air invisibly dumping out of a typical refrigerator when the door is opened. 🙂

What if you could make your own DIY custom RV refrigerator that fixes all of these problems? Sure it might not be among the easiest projects you've done, and may even be among the most difficult. But what if you could?

Let's start with the most wasteful part -- by stopping all the cold air from dumping out. The easiest way to keep the air inside -- even when you open the door -- is to create a refrigerator that operates "on it's back," like chest freezer. Since cold air is denser and wants to go down, a top-opening refrigerator can be opened up over and over without spilling out the air. This helps it stay cool for most of the day without needing to run the power.

It's so obvious that you have to wonder why they don't all do this already! It's because the front-opening refrigerator/freezer is way more convenient in your everyday household for just grabbing what you need off the shelf instead of digging around for it like you do with an ice chest style freezer.

But how about for an RV? Even though you're starved for space, a couple of things make a small top-loader really convenient. Think about this -- Do you already use a camping cooler in your RV to store your drinks and stuff?

If you don't find that inconvenient to use, then small top-loading refrigerator (or a few of them) should be just as convenient. For a permanent installation, a good place might be under the fold-down "sofa" seats. You could even make a sofa out of the refrigerator! While it may seem a hassle to tell your buddy to get off the couch so you can check the fridge... honestly, how many times do you have to tell someone to get off the cooler so you can get a drink. Same thing, right?

Maybe you're wondering if a little fridge under the flip-down couch seats will give you enough fridge space. Well, how much space do you actually use? A good experiment might be to see how many coolers you need in order to store all the food you need for the next trip. Maybe you're camping with a family, and you find that a few coolers isn't enough, no matter how well you pack it... So you're kinda "stuck" with the big one you already have. But with some creativity maybe you can think up a handy way to keep the cold in when you open it -- maybe some kind of insulated "chest of drawers" design or even some of those clear plastic strips like they have in the back of the grocery store.

pot-in-pot refrigerator

Zeer Pot (Pot-in-Pot Evaporative Refrigerator)

But consider this: There are actually great ways to keep your food cool that don't require any non-renewable power at all. There's even an evaporative cooling device called a Zeer Pot that can chill food down near normal refrigeration temperatures in dry climates using nothing but water. Or if you're not living near the desert, maybe you can just use a modified camp cooler to handle the less critical stuff. Though making ice takes electricity, simply replacing a reusable blue ice pack in a super-insulated cooler every few days could really cut your energy costs.

So the question becomes...Is it possible that much of your fridge space is taken up foods that require only minimal cooling rather than full refrigeration?

While meats, dairy products, and cooked and processed foods will typically need full refrigeration below the FDA's easy-to-remember upper limit of 40°F (4°C), many raw fruits and vegetables don't require more than light refrigeration to stay crisp. (Just remember to wash them thoroughly as usual.) Many condiments, jam, salted butter, oils, and hard cheeses can also do fine with light "cooling." Check out this article for inspiration: 7 Foods That Can Survive Outside The Fridge.

Once you've (hopefully) downsized your full-refrigeration needs and moved some of it to a simple cooler, you can think about designing a more efficient refrigerator.

portable workbench

Would you find it handy to have a sturdy space-saving portable workbench you can easily stow away?

You can bet I totally do!

I was looking for an easy way to do my projects on the road, when I came across the Sta-bull Ta-bull project on 911Kisses.net. To say it was exactly what I was looking for is a bit of an understatement. As you’ll see in the video, I rushed so quickly to get the parts I needed that I made a number of short cuts that proved, shall we say, “very educational.”

Essentially the Mobile Workbench is a portable “saw-horse and vise” style workbench (ideally a Black & Decker Workmate 125) with a removable work surface, fold-up peg board wall to keep your tools handy-but-out-of-the-way, and a drawer to store any tools that you wish to stay with the work bench.

DIY portable workbench from MobileRik.comFeeling like I needed a usable workbench “like, yesterday”, I was a bit dismayed to discover that the recommended workbench isn’t sold in stores, although the Workmate 125 is easily available through Amazon or Ebay for $30 with free shipping.  Not wanting to wait for it to arrive, I checked my local Harbor Freight and picked up a cheap imitation on sale for just $16.99. Upon assembling it, I quickly figured out a few reasons why I should just order the Black & Decker (described in the video) and return the cheap U.S. General to Harbor Freight. But since I had a zillion projects on my agenda, I decided to just, as they say, “make it work!”

Knowing that I’d eventually swap it out for the Workmate, I wanted a way to make a less-than-permanent installation, leading to what’s become an interesting variation in quite a few respects. Some of the changes I made as what I consider to be all-around small improvements. But the biggest change was the “flexible” way I attached the top to the bench, so that you could potentially use it with different sets of legs, if you wanted to upgrade later or just rotate between different workbenches.

Of course you'll need to get the right parts to build one, so if this project interests you, then continue reading to get the instructions, and also see a video of a handy companion project -- A DIY Tripod Chair. 🙂




light fire with pee

Can you use your pee to start a fire?

You'll know after you see this! If you like survival and fire-making techniques, this video is a must see!

[Mobile Rik Notes: I totally didn't expect it was going to be about this. Nothing mysterious, but NOT something I ever would have thought of!]

 

If you liked this, be sure to check out my more detailed post How To Light An Emergency Fire Without A Match (Or Lighter).


instant warm water system for camping

Need ideas for quickly generating warm shower water?

Watch this amusing video showing a simple system using a water pump and heat exchanger coil. While it could certainly be improved upon with some easy modifications that would help it both heat up faster and be much safer, it's a great illustration of creative thinking, and a simple demonstration of exactly how an on-demand hot water system works. 

Here's his explanation of how it's made.

Here's my homemade warm water system for camping. I bypassed the water from an electric camping shower through a copper coil. The copper tubing I bought from a gas shop. It was very easy to bend into the coil shape. The tap water from the bucket warms quite nicely through this system. It takes the cold edge off the water. To make the water hotter recycle the water back into the bucket allowing it to then pass back through the coil. Great little system. Quite cheap overall. $30 shower including pump (from BCF) $15 butane gas cartridge burner (from K-Mart) $10 for the copper tubing (from Kleenheat gas) and $5 for some extra plastic tubing and $2 for some hose clamps (from Bunnings). All in all I'm quite happy with this system. I am looking at enclosing the coil and flame to stop wind blowing the flame out. Let me know what you think. Cheers guys.
Age from Perth, Western Australia.


The simplicity of the idea is really nice. He doesn't even need to use any electric pumps, because it pumps automatically using the thermosiphon principle. It could also be adapted to use any heating device, including a campfire, portable propane stove, indoor range, or a DIY gasifying wood stove like the one I use.

It would be interesting to see something like this installed more permanently... Maybe even running off of a small wood-burning rocket stove? It would seem to me that the trick for a permanent install would be to either 1) use the heat-exchanger coil as part of the stove, ex. as the pot stand, or 2) permanently wrap the copper coil around a heated element, such as the chimney of a rocket stove (which is actually under the burner).

Do you need to disinfect a few batches of water to make them safe to drink?

You can do this easily by setting a few bottles of clear water out in the sun for the duration of the day (or over two days if it's 1/2 cloudy).

This method, called SODIS (i.e. "SO-lar DIS-infection"), uses the sun's UVA rays to effectively kill bacteria and viruses. One requirement is that the water in the bottle be clear enough to read through. If you're starting with dirty water, you should strain it through a clean cloth and let it settle first.

(Note that this method won't actually filter the water -- it will simply kill pathogens. But there are easy ways to filter water, using a quick sand filter or, if you have a more permanent stationary installation, a biosand water filter.)