nanog mailing list archives
Re: rack power question
From: Petri Helenius <petri () helenius fi>
Date: Wed, 26 Mar 2008 15:06:43 +0200
Dorn Hetzel wrote:
I believe some of the calculations for hole/trench sizing per ton used for geothermal exchange heating/cooling applications rely on the seasonal nature of heating/cooling. I have heard that if you either heat or cool on a continuous permanent basis, year-round, then you need to allow for more hole or trench since the cold/heat doesn't have an off-season to equalize from the surrounding earth.That is definitely a factor. I do know that you can run such systems 24/7 for multiple months but whether the number is 3, 6 or 8 with the regular sizing I don't know. Obviously it also depends on what's the target temperature for incoming air, if you shoot for 12-13'C the warming of the hole cannot be more than a few degrees but for 17-20'C one would have double the margin to play with. It's also (depending on your kWh cost) economically feasible to combine geothermal pre-cooling with "traditional" chillers to take the outside air first from 40'C to 25'C and then chill it further more expensively. This also works the other way around for us in the colder climates where you actually need to heat up the inbound air. That way you'll also accelerate the cooling of the hole.I don't have hard facts on hand, but it might be a factor worth verifying.
I'm sure somebody on the list has the necessary math to work out how many joules one can push into a hole for one degree temperature rise.
Pete
Current thread:
- Re: rack power question, (continued)
- Re: rack power question Tony Finch (Mar 26)
- Re: rack power question Deepak Jain (Mar 25)
- Re: rack power question Paul Vixie (Mar 25)
- Re: rack power question chuck goolsbee (Mar 25)
- Re: rack power question Petri Helenius (Mar 25)
- Re: rack power question Paul Vixie (Mar 25)
- Re: rack power question William Herrin (Mar 25)
- Re: rack power question Paul Vixie (Mar 25)
- Re: rack power question Petri Helenius (Mar 25)
- Re: rack power question Dorn Hetzel (Mar 26)
- Re: rack power question Petri Helenius (Mar 26)
- RE: rack power question John Lee (Mar 25)
- Message not available
- Re: rack power question Paul Vixie (Mar 25)
- data center loading (was:Re: rack power question) Lamar Owen (Mar 26)
- Re: data center loading (was:Re: rack power question) Robert Boyle (Mar 26)
- Re: rack power question Joe Greco (Mar 22)
- Re: rack power question david raistrick (Mar 22)
- Re: rack power question Patrick Clochesy (Mar 22)
- Re: rack power question Tony Finch (Mar 26)