Portable Keg Cooler (a.k.a. R2-Beer2)




Introduction: Portable Keg Cooler (a.k.a. R2-Beer2)

I purchased a kegerator last year to enjoy cold beer on tap at home. Early this spring, I thought that it would be nice to make it portable for camping, parties, fishing trips, etc. After thinking a bit about hauling a refrigerator around (not to mention the need for electricity) I decided to build a large portable cooler designed to hold the keg and CO2 canister.

I considered constructing a jockey box but that got trumped by wanting a more enclosed system.

I looked around online for some ideas and found a few commercially available insulated coolers starting around $180. Too rich for my blood! in addition, those were typically not set up for a CO2 driven system but more towards a one-night keg killer party with a standard air tap.

As with most of my projects like this that drive my wife crazy, I talked about it for a few weeks, researched on the 'net, and had a fairly detailed plan in my head by the time I started buying materials.

Step 1: Materials


1. 55 Gallon Plastic Barrel (used) - $10
2. 30 Gallon Plastic Barrel (used) - $10
3. 4' x 8' x 2" Extruded Polystyrene Insulation - $28
4. Shower Drain + Reducer - $??
5. Misc PVC Fittings and pipe - left over from previous plumbing projects
6. PVC Ball Valve - $??
7. Thermos - $5
8. Casters (4) - $12
9. 4' x 8' x 1/2" Faced Insulation - $9
10. Can of "Great Stuff" - $6
11. 4" x 7/8" Corner Brace (2) - $5
12. Aluminum Tape, spray glue, plywood, screws, etc. - Extra stuff laying about

Grand Total = about $105 (figure $20 for the stuff that I don't recall the price)

Step 2: Big Drum Prep

Cut the lid off the big drum. Something to watch out for here is if there are any left-over chemicals in the drum (particularly if they are explosive, corrosive, acidic, or extremely basic). The one that I obtained previously contained car-washing chemicals that I saved in a gallon milk jug (including the label). I'm still figuring out if I can use that on my car or if I need to take it to the hazardous waste drop-off.

Before cutting, draw a line around the top and use that as a guide for the saw. The plastic cuts fairly easily and a jig saw makes quick work of it. I left about 1" of the sidewall attached to the lid. If doing it again, I would leave about 2-1/4" so I could insulate the lid with the pink foam board (more on that later). Give the drum a good washing out. It doesn't have to be perfect as the beer you drink will never touch it.

Set the drum aside and let it air out a bit.

Step 3: Small Drum Prep

My small drum had been used for rainwater collection so other than being a bit dirty, it didn't take much clean-up. It necked down around the top so I cut about 2" off the open end.

If you have a spare keg handy, this is an excellent time to size everything up.

Step 4: Drain and Bottom Support

Next, assemble the drain, reducer, and elbow. Mine came out to just over 4" tall. To allow room for the drain as well and insulate the bottom, the inner barrel will need to be elevated.

Cut two pieces of plywood to the appropriate dimensions to fit inside the big drum and make a nice sturdy "X" with a couple of cuts in the center. I added 2" x 2" chunks on the side to hold everything together, but that isn't really necessary.

Check for size and start cutting the foam board to fit the spaces between the supports. Once everything looks good, put the small drum inside and mark the hole for the drain. Mount the drain and check everything for fit.

Step 5: Starting to Come Together Now...

Cut a few strips of insulation and brace the small drum inside of the large one. Cut an access hole in the bottom of the large barrel under the drain.

Finish out the plumbing by adding a short pipe from the drain, another elbow, and the ball valve. The valve is optional but will allow for controlled draining of the cooler.

At this point, mount the angle brackets that will hold up the CO2 canister with some bolts and fender washers. I neglected to do this until later (Step 7).

Step 6: Insulate Away!

Cut a bunch of 2" x 2" strips of the foam insulation. These should be at least as long as the drum is high. Push the strips down between the two drums. These will provide the majority of the insulation.

Once all the strips are in, fill in the gaps with the "Great Stuff". Don't forget to fill in the access hole in the bottom as well.

Go have a beer and wait for everything to set up.

Once the Great Stuff is cured, trim things up nice and neat.

Considering all the time that it took to cut the strips of insulation, I considered using Great Stuff all the way around. But, I think that would have taken way too many cans and blown the budget. I also looked around for some marine-style pour in insulation but was not able to find any locally.

Step 7: Final Steps

Getting almost to the end now....

Flip the whole works over and mount the castors. The bottom support boards will provide a good solid mounting for this.

Put the keg in the cooler and drill a hole for the tapper. It will need to be above the edge of the keg to allow room for the hose.

I made the mistake of not mounting the brackets before it was too late to just use bolts and washers. As a result, I had to use drywall anchors. Either way, time to mount the 1 gallon jug on the outside to hold the CO2 canister. Screw the bottom of the jug onto the brackets and add a strap to make sure the canister will be secure.

Step 8: Lid and Finishing Touches

Remember way back in Step 1, I mentioned that I should have cut the lid a bit deeper? Instead of being able to use the rest of my pink foam board, I had to purchase some 1/2" insulation for the lid. Cut insulation to size and secure to lid with spray glue.

The pink insulation ring was added to keep the lid from moving around and to allow the hoses room to extend up from the top of the keg. The weather-stripping is there to provide a good seal to the cooler.

For a finishing touch, I added aluminum tape to the top of the cooler to cover the insulation and keep water out. I also tried to be generous with the tape on the lid.

Step 9: Final Result

For the debut, I put a 1/2 full cold keg in with 50 pounds of ice. Let me just say, it was the hit of the party! The ice easily outlasted the beer and 48 hours later I disassembled the cooler and dumped out about 20 pounds of ice that still remained. A more typical situation for me would be a weekend fishing or camping trip and I will need to update this instructable once I know how well it holds up after a full day in the sun. For multiple days, the plan is to just drain out the excess water and then add ice as needed to the top.

The only thing that I have remaining on my list is to add some latches to the lid and pimp it up a bit with some LED ground effects.

As I mentioned before, total cost was about $105. The time commitment was around 20 hours or so.


2009_09_08 - UPDATE! - I had a Labor Day Weekend Beach Party and once again the R2BEER2 was a huge hit. With a full keg and about 30 pounds of ice, the ice lasted all weekend of 80-90 degree temps. Unfortunately, the beer ran out much too quickly.

2 People Made This Project!


  • Super-Size Speed Challenge

    Super-Size Speed Challenge
  • Backyard Contest

    Backyard Contest
  • Exercise Speed Challenge

    Exercise Speed Challenge

12 Discussions


6 years ago on Introduction

Your R2Beer2 has been an inspiration for
me to build one of my own. I made mine with a different kind of top. I
cut away from the top of the outer barrel keeping the lip intact. The
guy I get barrels from has lids that fit over the top of the outer
barrel. I sandwiched two lids together with some foam board insulation
along with some silver bubble wrap radiant barrier. I added a round
piece of varnished plywood and installed a kegerator tower. I made a
tower cooler whose fan plugs into a USB input for ease of using a
battery/car charger. I taped two small strings of battery powered LED
Xmas lights to the inside of the outer barrel and filled it with pour
insulation I got from Tap Plastic ($40). We used it at a 3 day party in 90+ degree heat. We filled it with 3 bags of ice on Friday, and the picture below shows it on Sunday afternoon with most of the ice still there. I'll post pictures of things
that differ from the original R2Beer2.

10314773_615934688503664_2797550608165548765_n.jpgGas Line Installed.jpgGas line disconnected.jpgbottom gas line.jpgRadiant Barrier.jpgjBatteries.jpgX-30.jpgFoam.jpgcut foam.jpgDaytime finish.jpgLights.jpgwith dolly.jpgIce.jpg

Reply 5 years ago on Introduction

Beautiful job. Very well done. The lights add a nice touch!

If I ever do another one of these, I'll go with the pourable insulation.


Reply 5 years ago on Introduction

Alright, I have been shopping around for some poly expandable foams and the one you chose looks to be pretty good for the price. When you poured the mix, did you use all of it and it ended up being just about perfect for you? Also how well does it insulate, if the cooling tower was not on? Thanks!


7 years ago on Introduction

I've built two of these (modified slightly) and everyone loves them. Thanks for the well-documented build.

With the two I built...
Modifications include:
1) Didn't insulate top or bottom; oversight on my part, but still performed well (ice outlasted keg by days)
2) I used 3/4" rigid insulation, cut into strips but left the film on one side, so it could wrap the keg like a jacket, then wrapped that with some eco-fiberglass stuff (didn't want to buy more rigid insulation). I inserted the entire wrapped 35 gal drum into the 55 gal drum, as opposed to inserted insulation in between the two. Used one great stuff canister to fill in voids at top, but couldn't get it more than 12" deep into the voids between the rigid insulation, otherwise I probably would have used more.
3) I mounted the faucet on some 2x4s poking out the top and ran lines in through the threaded holes in the cap, overflow beer drained towards the cap and into the ice bath
4) No casters or drain line

Couple Questions:
1) How important is the drain line? I can't imagine a situation where you need to drain the water... maybe because my kegs are always empty before ice/water needed to be drained, so I would just pull the keg out and tip the cooler over.
2) Really just throwing out an idea: for the next set I think I'm going to use marine pour insulation and entrain it with packing peanuts, since the insulation is $40/cf (ft^3), and the void in between the two drums is about 2.7 cf. Any thoughts?


Reply 7 years ago on Introduction

1. I use the drain line when the keg is outlasting the ice. It is much easier than tipping over the barrel when refilling. If you are killing the keg in a day or two, no need for one. If you are using it all week in 90 degree heat, the drain is nice.

2. I like your idea with the peanuts. One reason I didn't use the marine pour was that it is so expensive. I would probably go with extruded styrofoam peanuts if you can find them. The expanded styrofoam will absorb water over time if they are saturated. Of course, if they are encapsulated in marine pour, that shouldn't be a problem.
3. If you have any pictures, please post!


10 years ago on Introduction

I am a college student and am looking for a little extra cash so i have been selling shrimp at the flea market and been doing so well i need to upgrade from igloo coolers to something larger. I have found a 35 gallon barrel and a 55 gallon barrel and am trying to make a larger cooler. Do you know of anyway to use the co2 canster to help cool the barrel via co2?


Reply 8 years ago on Introduction

For shrimp, you'd really want to use regular ice. CO2 can get expensive if you're not buying it in bulk (the beer guys charge about $5/lbs vs $.75/lbs for 100lbs). Also, regulating the expansion is doable, but not really worth the trouble.

Dry ice would probably freeze everything in about an hour.


Reply 10 years ago on Introduction

Theoretically, that could be done by plumbing up some type of an expansion chamber (as the CO2 expands it will absorb some heat) BUT, unless you have a free source of CO2, it would get very expensive. The amount of CO2 that it would take to keep a keg cool would quickly outstrip the cost of keeping things cold with ice. Of course, you could always discharge a CO2 fire extinguisher in there! :) If you are looking for a longer-term solution, the keggerator route may be better. I've seen some pretty reasonable ones on Craigslist (~$125 or so, search for "keg"). Good Luck.


11 years ago on Step 9

Awesome Job! This is exactly what I was dreaming up, just wasn't sure where to find the 55 gal and 30 gal drums. Where would be a few good spots to try? How long does the ice last out in the sun?


Reply 11 years ago on Step 9

Glad that you like it! I haven't done an outside sun test. Two inches of the extruded polystyrene should give an R-10 insulation factor. The R-factor on the extruded poly is the highest that I could find that was readily available and not prohibitively expensive. The next significant step up gets into very high buck materials or vacuum. Most standard coolers seem to have around 1/2 - 1" or so of insulation and I think the "super" coolers are closer to 2". With the 2" of insulation in this thing and starting out with a cold keg and a full load of ice, I think it will easily last a day in the sun but have yet to try it (have an outing planned in a few months where it will get a full test). As far as finding drums, that took me awhile. I started out with looking on Craigslist and doing a lot of asking around. I did find a businesses that cleans out and recycles drums (they were asking about $25). I posted an add on Craigslist as well and got several responses. I paid $10 for each of my drums. Not sure what the small one had in it but the large one was from a gas station car wash (you could ask there as well). Good luck!


Reply 9 years ago on Introduction

The ice generally will last around 2 days in full sun and 95 degree heat (with the keg getting hit on a regular basis). Better insulation in the lid would increase this. Additionally, I may paint the lid white.