Issue link: http://digital.corporatepress.com/i/186210
prescriptive well field installation specifications and constant on-site supervision of the installation contractors is required, and is not optional, based on extensive forensic evidence of why systems ultimately fail. Within the first week of this particular project, it was found that each 500-ft well was only 480 ft deep, a 20 ft discrepancy on each well. Some may say, "So what's the big deal?" The big deal is that when applied to over 200 wells, this translates to some 4,000 ft of lost heat exchanger, IT'S ENTIRELY POSSIBLE FOR A SYSTEM TO BE MUCH LARGER THAN IT NEEDS TO BE, YET STILL FAIL OVER TIME. not to mention the extra $32,000 (at $8/ft) in profit to the installer. Short drills are common for several reasons: 1) the driller comes to the site with the wrong equipment, often because the specifications and project subsurface information wasn't specific enough; 2) high yielding rock fractures are encountered and, without the right capacity lift equipment to get the tailings out, they stop; and 3) there isn't anyone supervising the process. There are only two ways to prevent these things from happening: tight specifications and constant supervision—both of which will guarantee a properly installed field. Remember, there is only one opportunity to get this right. Accurately quantifying field performance is an important step in designing a system that is the proper size and capacity. If done right, optimized geoexchange systems can be one of the most cost-effective, powerful options to accomplish the goal of improved energy efficiency and reduced carbon emissions. Bill Johnson is vice president at Haley & Aldrich Inc. in Manchester, NH. He can be reached at wjohnson@haleyaldrich.com. Paul Ormond is vice president/geothermal manager at Haley & Aldrich, Inc. and can be reached at pormond@haleyaldrich.com; this is his first article for Facilities Manager. The authors wish to thank Susan Kleinman for her editorial assistance with this article. Ugly, Leaking Tile Shower Pans? Don't Replace, Refinish! Our proprietary surface refinishing process eliminates costly replacement of leaking shower pans, damaged tile, countertops and impossible-to-clean bathtubs. LESSONS LEARNED Ultimately, for this project, an independent design consultant well versed in design and optimization techniques was able to rescue the project from failure. The drilling contractor was held to a higher level of performance and the system was redesigned with additional equipment which, not only addressed design deficiencies, but actually decreased project costs. This resulted in improved long-term thermal and financial performance. Schedule work now for the upcoming holiday break! See case studies at: MiracleMethod.com/collegehousing All Work Guaranteed Each franchise is independently owned and operated. Call 800 444-8827 for an estimate or referral Facilities Manager | september/october 2013 | 63