Pre Chilling Water for Plate Chiller

[Green Wolf]

I am starting up a 2 BBL capacity brewery near Albany, NY (Schoharie County) and have been playing with an idea to pre-chill the water being sent to my plate chiller.

What I have at my disposal are two 4' x 8' x 3" hot water solar panels that no longer have their glass tops. If I attach the two solar panels together, face-to-face, and plumb them in unison, you would then have a long enclosed, insulated box with all those two lengths of copper absorber plates & tubing on the inside.

Next, I would cut out some holes in the casement and attach some peltier devices (small thermoelectric cooling units (sometimes referred to as TEC units)) to the copper absorber plates.

Lastly, I would mount this monster on the wall and plumb it in between our village water supply and the wort chiller (a Therma-line 31 plate chiller).

Questions I have would be:

1. Are the peltier devices beefy enough to cool down the passing water by 10 - 30 degrees?
2. Would it be better to deconstruct two or three mini fridges and stick the evaporator plates in the box?
3. Is this a completely nonsensical idea.

Cheers,

Justin

[AnthonyB]

I think the answer to number 3 is yes. Peltiers are terribly inefficient at the moment.. the number of them that you would need to have any real effect on temperature will be significant, not to mention the current draw... which will probably be several factors more electricity (relative to the BTUs) used than a comparably sized refrigeration unit (glycol, walk-in, whatever).

[ChesterBrew]

Seems far cheaper/simpler to pre-chill the water by buying an ice machine, and treating the water via a series of coils inside the ice chamber of the ice machine.

[Green Wolf]

I was wondering if the peltiers would be too inefficient. Thanks!

[panadero]

Coming from VT, and now in MI, I would try seeing what you can cool to without prechilling, first. I have a thermaline 49 plate on my 10 bbl system, and I know that is more cooling power, but in the dead of summer I can chill to 74 degrees at a 1 to 1.25 ratio wort to water. in the winter I can hit a fifty degree lager at the same rate. I would guess using a bit more water and a slower pass thru time you could get down pretty low. The diy prechiller would be fun to try, though! If you had refrigeration space, a three bbl tank inside with cold tap water the day before would get down overnight. I know people who do this, then run it thru the hx.
Just a few ideas, hope it helps.
David

[TGTimm]

We recover the warm water from the HX to use in our hot liquor system. I haven't done any calculations on this, but I think the savings in using 140 F water to start our hot liquor is far more efficient than pre-chilling would ever be. At your latitude, isn't your city water at around 45-50 F already?

[Green Wolf]

We recover the warm water from the HX to use in our hot liquor system. I haven't done any calculations on this, but I think the savings in using 140 F water to start our hot liquor is far more efficient than pre-chilling would ever be. At your latitude, isn't your city water at around 45-50 F already?

Good point. We aren't even up and running yet, and don't know how efficient the chiller is going to be on our 2 BBL batches. Trying to play with pre-chilling the water might not even be necessary.