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. I don't have hard facts on hand, but it might be a factor worth verifying. On Wed, Mar 26, 2008 at 2:23 AM, Petri Helenius <[EMAIL PROTECTED]> wrote: > > Paul Vixie wrote: > > > > aside from the corrosive nature of the salt and other minerals, there is > an > > unbelievable maze of permits from various layers of government since > there's > > a protected marshland as well as habitat restoration within a few miles. > i > > think it's safe to say that Sun Quentin could not be built under current > > rules. > > > The ones I have are MDPE (Medium Density Polyethylene) and I haven't > understood that the plastic would have corrosive features. Obviously it > can come down to regulation depending on what you use as a cooling agent > but water is very effective if there is no fear of freezing (I use > ethanol for that reason). The whole system is closed circuit, I'm not > pumping water out of the ground but circulating the ethanol in the > vertical ground piping of approximately 360 meters. The amount of slurry > that came out of the hole was in order of 5-6 cubic meters. Cannot > remember exactly what the individual parts cost but the total investment > was less than $10k. (drilling, piping, circulation, air chiller, fluids, > etc.) for a system with somewhat over 4kW of cooling capacity. (I'm > limited by the airflow, not by the ground hole if the calculations prove > correct) > > Pete > >