Re: rack power question

["Dorn Hetzel" <dhetzel () gmail com>]

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 <petri () helenius fi> 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