We have a project in-house where the client wants to use a GCHP system in a small office building. Relatively small building, nominal 40 tons load, using individual WSHP's and a vertical borefield. The building is heating dominated, by about 2:1. I've been doing HVAC design for over 30 years, but this will be a first. Well testing has been performed, data in hand, and while the Architect is still laying out the building, we have hourly loads via Trace on similar building nearby. Have reviewed piles of literature, and it appears I'm going to need some additional software. While ASHRAE/Kavanaugh did a good job of working through an example, doing this multiple times to get this design sorted out will burn much more time/$ than the cost of some software. $3000 software (GLD) for a project of this size is out of the question, so have narrowed it down to GLHE Pro4 or GchpCalc. Both of these appear to provide what we need, based upon the respective websites and on-line Users Manuals. Has anybody seen a comparison of these two systems? Or user reviews? From what I can see, the GLHE Pro4 software looks significantly more polished, but the GchpCalc flavor is based on/loosely favored by the Guru in this field, Mr Kavavaugh. These guys: ftp://ftp.aidea.org/Geothermal/vertical gshp.pdf have a great synopsis on the mathematical basis for several programs, but not much commentary regarding use. Interesting that the GLD software is not mentioned. Would appreciate any feedback from anyone who has used both these programs. TIA
Software Not too sure of the others, but I can run the numbers through GLD as it sounds like you've done all the work? I've mucked around with software and I keep, begrudgingly, coming back to GLD Might have to make it a bit more official than this, depending on liability. But I was thinking about how I enjoy Scotch
urthboy - Thanks for the response. And I may take you up on your offer as we get into this... Good to see there is some humour on this site. I sprang (is that actually a word?) for GLHEPRO 4 yesterday, and will start playing with it next week. Regards.
What happened so far/ ? Been tracking loops (commercially then for a first, Dayton Ohio, late- Dr John Jones and PE ME Michael Rice, mentors, and later the late David Heart of TETCO (and temps since 1980, hands on 1700+) , Spoke w/ Dr Steve K, ~ 6 years ago about Hybrids of Earth-Tower w:w series vs. straight GLHE 80-Ton Church. several college ansd school notes tracked and installed loop on a couple schools. Re-Designed for one highschool , the headers, and sugg same to Forte Knox/ and Trane contractor then... still in operation: 3:1 heat dominant, 52fEarth~ zone 5.1/2 6300 DD, some -12 below zero winters peaks 2-nights in a row ( last 10 years ~ 4 below zero ) 191 ft below grade vertical bores per COMPRESSOR actual labeled ton (not by rated size-"tons") Friedrich units, 1983 in clays and shales and we gravel overburdens to into wet sandy boreholes: have found about 43-46 btuh per foot of usable damp borehole to bounce off of the heat of extraction/absorption ~ 2.8- 2.9 gal/compressor actual ton in 34-to-35f Earth-Coupled Loop/ GLE/ ECL Entering Fluids of not more than 22% glycols or not more than 18% Methanol, respectively. Some tower chem techs say keep the anitfreeze above 16% or add antibacterial agents.
