Laboratory buildings provide the greatest potential for operational energy savings as compared to almost all other building types due to their high percentage of outside air, lab equipment, and often-complex control systems. Per the EPA, labs (on average) consume 5 to10 times as much energy on a square- foot basis as a typical office building in the same climate. Furthermore, a single constant volume fume hood will utilize as much energy per year as single family home. With the increasing costs of energy and renewed focus on the bottom-line, more and more companies & institutions have focused on their existing building and operations. Furthermore, corporate/institutional policies to reduce greenhouse emissions and/or energy consumption by building or site continue to gain ground, which in turn brings real professional and financial justification to these programs.
The first step in reducing energy consumption is to gain an understanding on how the building operates
– both at the infrastructure level, but equally important on the user level. Trending of key variables of a building’s operations can often be reported on directly through the building management system or recorded through temporary meters/sensors. Simple assessments include, “… are lights kept on during unoccupied periods?”, “… are the fume hood sashes closed?”, “… are the air handlers cooling and heating at the same time?”. Often the best approach is to have a professional engineer perform an energy audit of the building. These energy audits can range from upper-level assessments to full-scale – in depth review and analysis.
Zero-cost improvements are the best place to start to achieve immediate energy savings without any capital investment. These typically include improving the energy-savings mindset, awareness, and culture of the lab users and building operators. Closing fume hood sashes can typically save at least 50% of the airflow from their open (i.e. 18” sash height) position. Turning lights off during unoccupied periods is the 2nd most effective energy reduction strategy. Each of these zero-cost improvements can be base lined by performing shadow studies of the lab for a week and then immediate improvements can be achieved through the communication of these observations to the lab users. Continuous encouragement and reinforcement often yield long-term results and affects cultural change.
Since the airflow delivered to the lab spaces requires appreciable amount of energy to condition the air
(filter, heat, humidify, cool, dehumidify) as well as deliver the air (fan energy), this is often one of the greatest savings potentials for a lab building once the zero-cost improvements are performed. Working together with the company/institution’s environmental, health, and safety (ES&H) group to review occupied and unoccupied air change rates, temperature set points, and conversion of bypass hoods (CV) to restricted bypass (VAV) can often yield dramatic savings. This is especially true of older facilities, which were designed and operated at high air change rates (i.e. 12-18 air changes/hour) versus today’s more progressive designs of (4 – 8 air changes/hour). Its important to note that depending upon the reduction in airflow for the labs, some distribution changes may be necessary to ensure that the airflow distribution and temperature set points are not adversely impacted.
The location of the lab equipment should also be reviewed to ensure that they are provided with sufficient clearance for cooling airflow for any of the refrigeration systems. This is especially true for lab freezers, refrigerators, and incubators. Furthermore, the condenser coils on this equipment should be inspected and cleaned (just like your home refrigerator). Without sufficient clearance and/or dirty condenser coils, the refrigeration system will have to work harder (draw more power & reject more heat). An assessment of the lab equipment that requires exhaust (i.e. fume hoods, thimble or hard-connected BSCs, etc.) is also recommended to determine if the equipment is still in active-use by the researches or whether they have become a “storage” area for materials and/or chemicals. Any equipment not in gainful use or being used improperly (i.e. storage of chemicals in a fume hood) should be considered for removal to provide a safer environment as well as the real energy savings.
Retro or re-commissioning of the building’s engineering infrastructure is key to ensure that the systems
and equipment are operating at their peak performance. The commissioning process can identify and provide corrective recommendations to a wide variety of issues – ranging from incorrectly operated equipment, simultaneous heating/cooling, clogged filters/strainers, over-ridden controls, poor controls
– failed sensors, and incorrect set points. Post occupancy commissioning is an investment with often-
immediate payback for today’s complex buildings.
Help! – There are some excellent utility incentives, rebates, and training opportunities that are sponsored by the Massachusetts’s electric and gas utility companies & the Mass Department of Energy Resources. Significant incentives are available for VFDs, lighting upgrades, as well as select equipment upgrades. Refer to http://www.masssave.com
While the amount of new lab construction has decreased over the past five years, the opportunity to improve the energy efficiency of the large portfolio of lab buildings in the region is significant. By lowering the operational energy costs, additional funds will be available to support the true purpose of these buildings – research.
Cheers.
This article was written by Chad A. Wisler, PE LEED AP BD+C, Managing Principal of Vanderweil Engineers, LLP