Heat and Energy Recovery
An enormous amount of energy is required to heat and cool the air brought in during frequent air changes. Installing energy-recovery systems can substantially reduce the energy use of laboratories. These systems recycle thermal energy from exhaust air by recovering heat and cooling from the hood and general exhaust. This energy is then transferred back into the air-intake system for redistribution into the building. In other words, new air is supplied into the laboratories, but the heat (or cooling) that is latent in the old air is transferred into the new air via these energy-recovery systems, so the new air requires less energy to condition.
There are many types of heat-recovery systems that can be utilized in building retrofits. Rotary enthalpy wheels, fixed plates, heat pipes and run-around loops are popular. Choosing the appropriate system depends on a variety of factors, including the existing building’s mechanical system and location of fresh-air intake and exhaust, as well as the climate. With the right application, these systems can be very cost-effective. Enthalpy wheels, for instance, can reduce natural-gas usage by about 50 percent with even higher savings in cold climates. Heat pipe and run-around loop systems can achieve gas savings of 35 to 45 percent.
Energy-recovery systems for laboratories can be implemented for minimal cost and produce an almost immediate payback. In addition, utility companies are eager to support such energy savings with significant rebate incentives.
Retrocommissioning
As a laboratory building ages, its mechanical systems degrade. Retrocommissioning is a process that seeks to improve how building equipment and systems function together. It helps ensure the building operates as intended and that building staff can operate and maintain the building’s systems and equipment. During retrocommissioning, the equipment is comprehensively tested, adjusted and calibrated so it is functioning as efficiently as possible.
Studies, such as “Re-tuning Buildings: Six Steps to Energy Savings with Fast Payback,” by the Institute for Building Efficiency, an initiative of Milwaukee-based Johnson Controls, or “Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse Gas Emissions” by Lawrence Berkeley National Laboratory, Berkeley, Calif., have shown the average measured utility savings after retrocommissioning is about 20 percent with simple paybacks ranging from three months to two years.
Reconfiguration and Mobility
Reconfiguring laboratories into a more open layout can provide opportunities for even more energy savings. Updating these laboratories to bring in daylight—thus reducing the need for artificial light—can be challenging. To achieve this goal, laboratories should be located along the building exterior to provide natural light and views. If labs are located in the building interior, enclosed existing walls can be retrofitted with glass openings to bring in natural light.
Well-designed labs must be able to meet changing requirements in research and teaching, avoiding the environmental and financial cost—not to mention inconvenience—of major rehabs. Lab and office casework should accommodate simple and cost-effective changes throughout the life cycle of the building. Consider using mobile benches with modular under-bench units and cabinetry and mobile desk units, fume cupboards and sinks.
New furniture systems have flexible connections for many types of services, including gas, water, electricity, supply and exhaust air, data and electronics. The utilities plug into the benches from the ceiling and unplug if benches move to another area. Also, to maintain high indoor-air quality, furniture materials with low emissions should be specified. You can green a laboratory space by choosing materials that contain recycled content and can be recycled when they are no longer needed.
Of course, upgrading mechanical systems and improving the building envelope with high-performance glazing and additional insulation are the best means of energy conservation in older laboratories. However, if building owners and facility managers are not prepared for these upfront costs, they can employ a multi-pronged approach to reduce energy consumption by retrofitting and retrocommissioning existing equipment, as well as reconfiguring the space to improve daylight and reduce lighting costs.
PHOTOS: Goldman Reindorf Architects Inc.