Dealing with frequent power outages.

[eddiek85]

I live in Vietnam where there are frequently scheduledpower outages that last 4-5 hours. I was well aware of this and planned to do some resaerch into what kind of generator I would want to keep my fermentation chamber (chest freezer) and eventually a modified air conditioner (glycol chiller). What I didn't expect was that the scheduled power outage would get scheduled 2 days after I brewed my first batch!

So the notice went up today today and the power goes out the day after tomorrow for 4-5 hours. I have a 60L plastic fermentation vessel inside of a chest freezer. I don't want to jump to gun and end up buying a generator now because I really want to do my research to future proof for potentially needs.

TLDR; Would it be ok to just dump ice inside of the chest freezer maybe 1/3 or 1/2 the height of where the beer is in the fermenter and leave it for 4 hours? How much would this mess up the batch? Any better suggestions?

Thanks very much!

 

[mattd2]

What is the ambient temp at the moment? If you have a decent chest freezer with good seals then you likely will get away with doing nothing.

 

[madscientist451]

If you have freezer space, you can freeze 1 and 2 liter plastic water bottles and have them ready when the power goes off. You'll have to experiment a little to see how many you need to maintain temperature. Put them in 1/2 hour before the power goes off.
The chest freezer will probably be ok for 4-5 hours, maybe without doing a whole lot. Run some tests and see what happens. I'd skip the glycol equipment unless you want to get a backup generator.

 

[mongoose33]

The more thermal mass you have in your freezer, the greater the resistance to power being off 4-5 hours. That is, if all you have in there is your fermenting beer, it'll warm up a lot faster than if you have, say, 20-40 liters of water at the same temperature as the beer.

You wouldn't want the temp of the thermal mass to be greater than the temp of the beer when you put it in there, else the freezer will work to cool that while cooling the beer too much.

If you have enough thermal mass in there, a few frozen bottles will be enough to hold it; might, depending on ambient, be enough in itself, but I'd use the frozen bottles anyway just to be sure.

 

[MaryB]

A chest freezer running at ale temps uses very little power. A good deep cycle battery and large(1500 watt minimum to handle compressor starting currents) inverter will easily get you through 4-5 hours where it will maybe run 2-3 times. I use a chest freezer as a fridge on my solar system and it draws very little beyond the startup surge current. Mine draws maybe 3 amps or 360 watts and in 24 hours keeping temps at 36 degrees it only uses 450 watts of power. It is a very efficient system and if you pack the excess space full of water bottles at whatever fermenting temp you use it may not even cycle in 4 hours. Key is mass at the temp you want to hold. Adding something frozen can really spike your temps down fast in one(I see it when I thaw meat).

 

[timdillon36]

I wouldnt worry about it much either. It sounds like the amount of time the power is to be out would take into consideration everyone that lives in the area and has a fridge or freezer. The temp might move a little but you know when the power will go out so if you turn it down a degree or 2 before that it will still be close when power comes back on.

I would check your temp controller to make sure it keeps your setpoints with the power being out.

Also, you might look into getting a UPS as your backup power.

 

[Jim311]

Unless it's extremely hot outside I don't see a 3-4 hour outage affecting much of anything. When I'm fermenting at ale temps the fridge hardly even runs at all. If I were expecting an outage, I'd probably set my fridge 3-4 degrees lower the night before to compensate, or do nothing at all.

 

[eddiek85]

Wow, thanks for coming through everyone. I've got some large bottles of water freezing and will throw those in there tomorrow and hope for the best.