Movement between each step of the assembly line is surprisingly low-tech. Simple metal carts like those used to reshelve library books litter the floor. Each is identifiable across the vast factory via brightly colored “lollipop” sign tags that protrude above the stacks of parts. Every cart represents another ERV on its way to completion.
The final assembly is the last step of the process and the one involving the most handcrafting, as the parts are screwed and the electronics wired together. It’s only here that the enthalpy wheels are inserted and a sophisticated energy recovery ventilator suddenly emerges from what was previously just a stack of seemingly spare parts.
LEED IMPLICATIONS The extent to which energy recovery can benefit building designers, engineers, and owners is dependent on location, with the entire eastern and central United States showing significant advantages in both the summer and winter. “A lot of states require energy recovery now,” states Jore, citing ASHRAE 90.1-2004 as the most commonly adopted standard for many buildings that receive public funding. “It strongly suggests what kind of energy recovery to use,” he says.
Greenheck has identified three prerequisites and five credits from the LEED-NC requirements that their ERVs can help achieve. Greenheck’s ERVs are already ahead of the curve. Jore notes that ASHRAE 189 is in public review and requires even higher performance that will necessitate energy recovery devices. “Our product is already there in terms of what they’re asking for in efficiencies,” he says.
DIFFERENT KINDS OF PAYBACK The earliest energy recovery units were developed by other manufacturers during the early 1970s, primarily for industrial environments. Interest waned when energy costs went down following the energy crisis of that decade. Greenheck eschewed the industrial market for ERVs, since contaminant-laden air streams posed problems with the mixing of indoor and outdoor air streams. The company entered the ERV market just over a decade ago with its own system for institutional and commercial applications. “Schools are a very big market for us,” explains marketing communications manager Cheryl Aderhold.
Many regular Greenheck customers are constantly expanding their facilities. Since implementing energy recovery reduces total energy loads, it’s often possible to add square footage while retaining older HVAC units. “It’s a significant amount of cooling you can reduce,” says Jore, citing a savings of 3 to 4 tons per 1,000 CFM. By adding an ERV, old systems can often meet the heating and cooling requirements of larger areas.
While operating bills will always be a factor, today’s increased demand for ERVs is based on costs of a different magnitude. More temperate climates—California and parts of Arizona, for example—don’t necessarily require air conditioning. “California is not a great place for us in terms of financial payback, but now there’s a whole other element,” says Jore. “It’s not a cost thing. It’s saving the environment.”
