Modular Geothermal System Pays Off for Ditch Witch Manufacturer
Modular Chiller System Uses Geothermal to Fight Energy Costs
At the time, Mazlahn was paving the way for compact trenchers that now efficiently install water, sewer and gas lines, and telecommunications, CATV and fiber optic cables across the globe. Malzahn’s original plan launched a more than 60-year history for Perry, Okla.-based The Charles Machine Works Inc. (CMW), as well as its leadership in manufacturing Ditch Witch branded equipment used in construction projects worldwide.
True to its longstanding reputation for innovating cutting-edge utility construction solutions, CMW has recently developed horizontal directional drilling (HDD) equipment which is being used in the growing geothermal industry. Rising fuel costs and an elevated interest in renewable energy technologies have made geothermal heating and cooling a more popular HVAC industry choice in recent years, particularly in relation to the exceptional comfort and long-term energy savings it can provide.
The company is not only innovative in its product development, but has exhibited an ongoing commitment to incorporating the latest construction technologies and methods into the design of its expanding headquarters campus. This has included three geothermal projects over the past 21 years––most recently, a 150-ton system for its 28,800 square foot product development center in the spring of 2012.
“As a company, we’ve made a living out of serving the underground construction industry, and to stay on top of the latest trends and understand the newest innovations, we figure there isn’t a better way than to install them at our own facilities,” said Tony Guinn, plant engineer for CMW.
Working with Stolhand Heating & Air Conditioning and Oklahoma City-based manufacturers’ representative firm Air Products Supply, CMW designed its latest geothermal project, a retrofit system for its product development center, with innovative new simultaneous heating and cooling heat pump units from neighboring Oklahoma City-based ClimaCool Corp. The three 50-ton ClimaCool SHC onDEMAND modular chiller units were specified to replace an antiquated reciprocating chiller-driven HVAC system installed during the building’s construction in 1978.
“As part of an overall assessment of how we could make our product development center more energy efficient, and ultimately shave a considerable amount of operating costs, we knew some significant HVAC upgrades would be in order,” said Guinn.
Darrell Stohland was keen on specifying the new SHC onDEMAND units from ClimaCool for several reasons. “I’d been to training with Air Products Supply and was highly impressed with the unit’s ability to generate heating and cooling simultaneously,” Stohland said. “The project goal was to save money, and a system like this that can blend energy versus just blast heat or cool seemed like the way to get that job done. Also, the comfort level of this type of system is exceptional, especially when considering the design of the building, which includes two levels of an open floor plan and a south-facing wall made entirely of windows.”
Each of the three, six-pipe SHC onDEMAND units also features a unique modular design with built-in redundancy with separate module electrical feeds and dual independent refrigeration circuits, allowing for the unit to maintain operation while individual modules are being serviced.
“The new SHC onDEMAND modular chiller unit offers dramatic energy saving benefits—potentially more than 50 percent when compared to traditional boiler/chiller systems,” said Ross Miglio, ClimaCool president. “It also features a patent-pending six-header design that eliminates the required space between and external to the modules, creating the smallest system operating footprint when compared to a typical simultaneous system.”
According to Darrin Beller, president of Air Products Supply, this ClimaCool configuration incorporates several notable features that maintain precise chilled and hot water temperatures, building loads and compressor run time equalization for ultimate operational efficiency.
“The SHC onDEMAND heat pump unit is an exceptional piece of equipment when it comes to reducing energy consumption,” Beller said. “Features such as the CoolLogic Control System and integral motorized valves for variable pumping can result in cooling efficiencies up to 25 EER and heating efficiencies up to 5 COP. This opens a lot of doors for us in supplying to projects that demand a high level of energy efficiency, including sustainable building projects, and the flexible nature of the system means it can be integrated with cooling towers, geothermal loops or hybrid systems.”
The new 150-ton system would also incorporate two existing air handlers with replacement Wilo brushless DC motorized pumps for load demand sensing. The controls system and fresh air vents with an economizer, considered state-of-the art when originally installed in 1978, would also be replaced with a web-based building automation system (BAS).
“The new BAS provides much more control than the previous system, and really brought mechanical operations to a whole new level in the building,” said Mark Furgason, sales and service manager at Automated Building Systems, which designed and installed the BAS.
Initial geothermal field drilling for the project began in September of 2011. “This was our first vertical loop field geothermal project on the campus,” said Guinn. In all, the field includes 168 400-foot deep boreholes with HDPE double U-bend pipe installed throughout.
The drilling was conducted in tandem with the construction of a separate foam-insulated 20-foot-by-24-foot mechanical building that would house the new ClimaCool units and ancillary HVAC system equipment. “With our original HVAC system, the chiller was external to the building, and the boiler, which we removed, had been installed in the shop,” Guinn said. “We really needed a separate space for the new equipment, and also had a goal of making it a showplace of sorts, to use as a model for how this innovative system looks and operates.”
Upon completion of the loop field in March of 2012, the ClimaCool unit was installed and initial flow testing was conducted.
“After the commissioning phase, the ClimaCool system has performed very well,” Guinn said. “We locked the thermostats at 73 degrees Fahrenheit to eliminate user fluctuations during last summer’s heat wave, and the system kept the building very cool and comfortable at that temperature.
Guinn additionally shared, “We’ve been operating on only half of the complete borehole field to date, as Ditch Witch is using part of the field for performance testing. When the testing is complete, we plan to use the full capacity of the field.”
“We are still waiting to see what happens when the system’s been operating longer-term, but we expect that we’ll be seeing about a $50,000 annual savings in operating costs,” Guinn continued. “This is much in part due to the highly energy efficient operation of the geothermal system, as well as how the ClimaCool units ideally capitalize on this type of energy.”
“The success of this project echoes ClimaCool’s history of innovation in developing and applying cutting-edge HVAC technology in commercial projects across the U.S.,” Miglio said. “Beginning with our early days as leaders in the supply of modular chillers to the U.S. market, ClimaCool has built on this legacy to become a premier manufacturer of ultimate comfort solutions like the SHC onDEMAND.”
According to Miglio, thousands of ClimaCool units are currently in operation throughout North America, with a dominant and growing concentration of successful simultaneous heating and cooling unit applications.
All ClimaCool modular chillers are designed to minimize installation time and costs, with individual modules that can fit through standard doorways and have low centers of gravity for easy transport via pallet jacks and forklifts. Modular chillers from ClimaCool are additionally engineered to streamline maintenance, with single-point electrical connections and waterside isolation valves that allow for the servicing of an individual module while the remaining modular chillers in the bank continue to operate. Their non-proprietary designs also afford contractors the ability to service the units without proprietary parts or factory technicians.
With a focus on system efficiency, ClimaCool has engineered its units with a holistic view on cooling, heat recovery, heat pump operation, geothermal capabilities, and simultaneous heating and cooling applications in mind. Looking toward the future, ClimaCool is focused on developing cutting-edge comfort solutions in alignment with dynamic industry needs, including those associated with energy costs, total cost of operation, redundancy, ease of installation, serviceability and refrigerant legislation.