Battery powered heat source for ferm chamber?

[ampersandrec]

My otherwise homebrew friendly wife has asked I keep the carboys outside, so I'm using a well insulated wood fermentation box in the backyard. The temp overnight was just right with my first try during the first few days while fermentation was active (68 degrees), but now that it's slowed down the temp is dropping more than I want it. The tricky part is that electricity isn't available where the chamber is, so I'd like to experiment with a small battery powered heat source in there overnight. Without a temp controller I think the battery powered ceramic heaters would be too strong. Anyone have another suggestion?

Thanks in advance!

 

[vera]

I would put a milk jug of hot water in the box.

 

[rhamilton]

Generating heat requires a good amount of energy - so much I don't think a battery powered solution is your best bet. It might be your best bet to do warm water jugs - they hold energy fairly well but you'll need to reheat them every so often which isn't ideal.

 

[onthekeg]

Can't you run an extension cord?

 

[ampersandrec]

Can't you run an extension cord?

I wish I could, but to be fair to her it would be a little unsightly. Plus our landlord is a bit of a utilities hawk, so he wouldn't care for that. There aren't any outside outlets (it's an old 1930's beach cottage) so it would take running an extension through a window, which wouldn't look very nice.

I like the hot water jug idea. Thanks guys!

 

[brettwasbtd]

Lets tackle the real problem....Now that your wife has been tackled, we can ask "What is it about the fermenters that relegates them tot he dog house?" - Smell? Size? Maybe if we can get around that, then you can get the beer back inside where it belongs

 

[ajm163]

the amount of energy needed to heat the space is going to be a function of the size of the space and how well insulated it is..... A small space that is very very very well insulated would not require a huge amount of energy but that being said we are not talking about 2 AA batteries ether. I think it could be done with a deep cycle truck or marine battery but how would you recharge it without running an extension cord???? solar???

 

[ampersandrec]

Lets tackle the real problem....Now that your wife has been tackled, we can ask "What is it about the fermenters that relegates them tot he dog house?" - Smell? Size? Maybe if we can get around that, then you can get the beer back inside where it belongs

Haha. That's a good question. It's answered very simply in my case. We have a 450sf house and just had a baby. There is literally no room. I'm one of the lucky few to have a wife that loves that I brew at home. We just need the space.

Some day, I'm going to hook up a solar panel with an inverter and battery and do some sort of temp controller, heat source and vent fan setup for the box. But that's a couple hundred bucks away...

 

[clay9_24]

i think that the cost of the batteries would be a bit cost prohibitive.

taking the above suggestions of a jug of hot water in their with them. you might look for a used solar pool heater to keep that jug toasty. just a suggestion not even sure if that would work.

 

[thepartsmancometh]

Look into passive solar heaters. I did some reading on them a while back, and they might help boost the temp on the cheap

Edit: here's a cool cheap solar collector
http://tlc.howstuffworks.com/home/solar-garage-furnace.htm

 

[ampersandrec]

I put four 2 liter soda bottles with water as hot as I could get out of the faucet in the ferm chamber last night. I checked in 6 or 8 hours later and the temp was 58 - basically no change and way lower than I want. So that didn't work. I guess time to look into battery powered lights, maybe something with rechargeable batteries.

I should note that the chamber is pretty big. It fits 4 carboys. It makes sense now that the hot water wouldn't work. If I have 15 gallons of beer that's at 58 degrees and put 2 gallons of 90 degree water in there, even if it all equalizes without any loss to the box or air that's not going to provide much of a bump in temperature.

 

[Logzor]

Buy a 5-g bucket of calcium chloride from the pool store.

Find an old 5-gallon bucket.

Fill with halfway with hot water then add 5+ cups of the calcium. This will generate a lot of heat. Not sure how long it will last but it could raise the temp enough to keep it stable for awhile.

This is the same stuff they use to melt snow in the winter.

This probably isn't cost effective but it's a step above using just hot-water from the tap.

Is the box insulated at all?

Have you considered making the top or side out of plexiglass to let in solar heat?

 

[Mb2658]

Careful. Along with heat you will produce hydrochloric acid.

 

[ampersandrec]

Is the box insulated at all?

The box is pretty well insulated. I'm the third owner, so I don't know the exact makeup, but it's 3/4 particle board inside and out with wall insulation in between. I put latches and weather stripping on it when I got it to make a good seal on the lid.


I think I might try my battery jump starter with a shop light hooked up to the inverter tonight. Maybe that would do it. If that does it I could buy another cheaper one and recharge it every couple weeks inside.

 

[Logzor]

Careful. Along with heat you will produce hydrochloric acid.

I mix up pure calcium chloride and water on a regular basis and dose it into my saltwater aquarium, it's not harmful in my experience. I make 5 gallons at a time and dose roughly 2 cups per gallon and there is no off-gassing of any kind. I've never been burnt by the solution, either.

You'll be using at least a 60w bulb, you'll be lucky to get 5 hours from your inverter...

I know my math might be way off but I'm guessing a 60w bulb would take just over 5AH to run for an hour, so if you have a 20AH battery then the bulb will go for 4 hours or so. Not sure how many AH your inverter has.

 

[Charlie_in_TX]

Best thing to do is use yeast meant for the temperature you are dealing with.

You will have a tough time heating with a battery. It takes about 500 lbs of batteries, charged, to store the same energy as 1 gal of water.

IMO, if you can't change yeast, you need a solar water heater. A black box with a plexiglass lid. Copper tube in it running back and forth. A barrel holding water inside your chamber. A small, solar powered pump to circulate water thru the tube in the box.