Refrigerator Wine Coolers

Before I built my wine cellar, I had two wine coolers, or refrigerators. The motor to cool the units ran virtually none stop, just like happens with your kitchen refrigerator. Obviously they were using a lot of energy.

With my basement wine cellar cooling unit, the unit only runs for perhaps five minutes every hour, often less. Obviously one small unit running for five minutes per hour uses less energy than two refrigerators running none stop. Even better, my wine cellar can hold 1,200 bottles, as compared to under 300 for more two wine fridges. That’s an obvious energy saving.

Why the difference? I’m not an engineer, but I assume it’s due to the fact that, once the wine cellar reaches the optimal temperature, the 1,000 bottles store the coolness, which keeps the cellar cool. Also, the wine cellar has far better insulation than a wine refrigerator, which helps to maintain the temperature.

Other than great insulation, and keeping the door closed, I have two other energy saving tips.

First, keep your wine cellar full. The more wine you have, the more mass you have to retain the temperature. If you can’t fill your wine cellar with wine, store pop, beer, vegetables or anything else to help retain the heat.

Second, during the coldest days of winter, half fill plastic jugs with water, and leave them outside overnight to freeze. Then, bring them into your wine cellar during the day. They will absorb heat while they cool, which saves energy. In effect you are bringing the cold air from outside into your wine cellar. That’s free air conditioning, and that’s using winter to your advantage.

Here’s the floor after applying the insulation:

Yes, it looks just like the walls look. The foam insulation does dry solid, but it is full of tiny air pockets, so you don’t want to walk on it, since you will likely compress the air pockets and lower the insulation value. That’s why we applied the plywood floor as soon as possible:

Yes, this picture also shows the drywall on the walls, but that’s the subject of my next post.

There are many different opinions on the proper insulation technique. One school of thought says that you should install a vapor barrier (a plastic sheet) on the outer side of the wall, and then mount your fiberglass insulation, and then your walls. A vapor barrier is essential to keep moisture from forming in the wine cellar or behind the walls.

We decided to use a different approach: spray foam insulation. The insulation is applied as a liquid, and expands as a foam, and then hardens as a “solid”. Our contractor blew the the foam into place, smoothed it out, and let it harden.

This approach has a number of advantages.

First, it’s relatively quick. The entire job can be done easily in half a day. If you were to install a plastic vapor barrier, then cut and install fiberglass insulation, and fasten it into place, the job would take much longer. You may be able to simply push the fiberglass into place in the walls, but gravity won’t allow you to do that in the ceiling; fastening is necessary. With spray foam, it’s quick and it’s done. Here’s how it looks in the ceiling.

Second, since the foam dries hard, there is no need for a separate vapor barrier. Fiberglass insulation will retain water if it gets wet, so a vapor barrier is essential. With “solid” insulation, water cannot penetrate, so a separate vapor barrier is not necessary.

Finally, as you can see with the ceiling picture, foam is great for filling in every “nook and cranny” in a ceiling or wall with wires, pipes and other impediments. Fiberglass insulation will not fit as tightly.

Therefore, my vote is for spray foam insulation.