“If half of the laboratories in the country achieved an energy efficiency improvement of 30 percent, that would result in a reduction of 84 trillion BTUs, which is the equivalent of more than two million households, a billion dollars in utility costs, and 16 million tons of CO2 emissions,” says Steve Riojas, HDR’s senior vice president and western region director for science and technology.

In addition to benefiting the environment, improved water and energy efficency also significantly reduces ongoing operating costs.

“Energy is the single largest operating expense in a laboratory, after staffing,” says Jim Wermes, HDR’s lead mechanical engineer in Phoenix.

The DOE recently partnered with the EPA to create Laboratories for the 21st Century (Labs21), a voluntary program specifically oriented to improving the environmental performance of laboratories in the U.S. The American Society of Heating and Refrigeration and Ventilation Engineers (ASHRAE) has also developed industry specific performance standards. ASHRAE 90.1 (which establishes benchmarks for energy efficency) and ASHRAE 62.1 (which establishes indoor air quality standards) are commonly used tools for designing sustainable facilities. While the United States Green Building Council’s LEED certification was originally established to improve the performance of office buildings, both Labs21 and ASHRAE address the demands of sustainable research facilities.

Recently completed work on leading-edge facilities at Brookhaven National Laboratory, Sandia National Laboratories, and Arizona State University feature a wide range of innovative solutions that significantly reduce resource consumption.

Water Harvesting

An innovative rooftop rainwater-harvesting system is proposed for the Brookhaven National Laboratory in Upton, N.Y., on Long Island. Brookhaven’s new National Synchrotron Light Source II facility includes a massive donut-shaped structure that has a rooftop of more than 300,000 sf. Long Island’s annual rainfall of more than 48 inches means the facility’s roof captures approximately 7.7 million gallons of storm water annually. In the proposal, that water is channeled from the facility’s roof into five underground storage tanks and then piped to the cooling towers and used for process water in the facility’s labs. Five adjacent lab buildings have the potential to implement rooftop rain harvesting systems that channel water into less expensive above-ground storage tanks so it can be piped into the building and used for non-potable uses.

“There is a higher first-cost impact that comes with creating a rain-harvesting system that needs to be considered. Storage tanks account for 61 percent of the first costs, so you don’t want to over-design the system,” says Lidia Berger, eastern director of HDR’s Sustainable Design Solutions in Alexandria, Va.

No-Cost/Low-Cost Strategies

One of the most successful water conservation measures at Brookhaven’s recently opened Center for Functional Nanomaterials (CFN) was xeriscaping that eliminated the need for irrigation at the site and resulted in significant first cost savings. Xeriscaping—the use of native plants and prairie-style grassing for landscaping—also reduces storm water runoff because prairie-style grasses have deep root systems that pull water from the soil, as opposed to conventional turf lawns which have shallow root systems.

“Irrigation accounts for more than 13 percent of water usage in your typical lab building. So xeriscaping can have a significant impact. It’s important to consider these types of no-cost/low-cost solutions first because they can reduce consumption tremendously without the expense of high-cost solutions,” says Berger.

Another significant low-cost solution implemented at CFN is the use of water efficient fixtures. These types of low-cost solutions garnered the facility six LEED credits and reduced potable water usage by 39 percent (based on the Energy Policy Act of 1992 benchmark).

Sensible Cooling

Sandia National Laboratories’ 98,000-sf interdisciplinary Center for Integrated Nanotechnologies (CINT) in Albuquerque, N.M., completed in 2005, utilized a number of inventive strategies to achieve a 50 percent reduction in the use of irrigation and process water, a 37 percent reduction in potable water consumption, and an energy efficiency that is 32 percent better than ASHRAE 90.1 standards.

One of the key sustainability features of the CINT facility is sensible cooling. To achieve this, the building utilizes a traditional four pipe HVAC system, but with the addition of two more sets of cooling pipes to create a six-pipe system. In this design, one of the chilled water systems runs above the space dew point, eliminating unnecessary dehumidification.

“When you don’t need dehumidification, the chillers can operate at a higher supply-water temperature, which increases chiller efficiency, or you can provide cooling directly from the cooling towers. So we have dehumidification only where it is needed. That’s where we picked up a vast majority of the improved energy efficency,” says Wermes.

The CINT project also achieves a significant reduction in the consumption of lighting energy by maximizing the use of ambient daylight.

“We targeted 65 percent of the spaces to exclusively use daylight, but fell short of that because of the value engineering process, which eliminated a lot of clerestory glass and a lighting control system to dim the lights when there was enough daylight. There is some task lighting, but it’s mostly provided by high-efficiency fluorescent and T5 bulbs,” says Wermes.

Process-Water Efficency

Cooling tower makeup and single pass cooling account for more than half the water use in modern lab buildings, according to Berger. Process water, defined as water used in the laboratory, is not specifically addressed by existing LEED guidelines. Since there are no official metrics for measuring process water efficiency, Sandia established a baseline for process water usage at CINT by looking at similar facilities. According to the data, the estimated baseline for non-potable water flow in a similar lab facility is approximately seven gallons per minute. Designers implemented extensive water conservation measures at CINT and reduced non-potable water flow to approximately 3.75 gallons per minute—a 50 percent reduction.

Successful process-water conservation strategies include design of a closed-loop process system, the collection of laboratory drain and waste water for use in cooling tower makeup, and designs that maximize cooling tower cycles of concentration.

Space-Demand Control Ventilation

The 250,000-sf Walter Cronkite School of Journalism uses an innovative space-demand controlled ventilation system. In addition to demand-control ventilation, space-demand control ventilation monitors individual space CO₂ levels and compares them against ambient CO₂ levels to reduce minimum air flow to a specific space. This further reduces the use of outside air during off hours, reduces energy consumption caused by over-ventilation, and improves indoor air quality.

“The benefit of space-demand control ventilation is that you can directly control the indoor air quality and provide the proper amount of ventilation for each space. You can accommodate higher occupant loads in large meeting rooms that might only be used twice a week. This is significant in a facility like the Cronkite School, which is designed to accommodate up to 3,000 people,” says Wermes.

To improve the indoor environment and increase energy efficiency, the Cronkite School implemented a two-stage cooling control system. With a single-stage cooling control system there is only one control valve that distributes chilled water to the cooling coils so each coil does half of the cooling. With a two-stage cooling control, each coil bank has its own control valve which reduces space humidity levels and reduces the amount of necessary reheating.

Risk Analysis Process

In order to assess the value of advanced sustainability features over the life cycle of a facility, HDR uses a proprietary tool called the Risk Analysis Process (RAP) to analyze the net benefits of a facility’s environmental performance with regards to energy and water consumption, air quality, and storm-water runoff, among other things. The outputs of the tool quantify the value of the project in terms of net present value, discounted payback period, return on investment, etc.

Sustainability features are weighted by economic factors that include capital costs, operating costs, incentive rebates, geographic location, productivity, and the time value of money. The impact of site-specific elements such as climate, soil type, and energy availability are considered in combination with possible options for irrigation, landscaping, and solar power.

“The process makes it possible to generate spreadsheets and graphs that can be shared with multiple stakeholders to show how well investments will pay off over time, and how things like greenhouse gas reduction and global warming are being addressed. This is where RAP considerations become really beneficial,” says Berger.

Lessons Learned

One of the most significant lessons learned is the importance of installing and maintaining a metering system.

“It’s critical that you go back and re-commission the building a year after it is open to ensure that it is performing the way it was intended. To do that, you have to install metering systems so you know, for example, how much water is being used for laboratories and for cooling tower makeup,” says Riojas.

Education of support staff is also a key part of ongoing performance.

“These buildings are complicated and the maintenance staff needs to go through a scrutinized educational period to make sure they understand how everything operates,” says Berger.

Riojas also emphasizes the importance of budgeting in sustainability features from the outset to prevent them from being value-engineered out of the final project.

“None of these projects had sustainability elements specifically budgeted in. They were just included in the mechanical, electrical, and plumbing budgets. So when it came down to the value engineering process, the decisions weren’t made on a cost-benefit ratio. So, you want to budget for sustainability features like water harvesting or energy efficency,” he says.

By Johnathon Allen

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