AFE May/June 2012 : Page 20
S tatus & T rends in Energy-Efﬁ cient & Sustainable Facilities An overview of ﬁ ve high-performance buildings incorporating eco-friendly elements from design and construction through day-to-day operations. Find out how incorporating the right sustainability elements into your facility can lead to lower operating costs and a better environment. uilding-energy use accounts for approximately 40 percent of total energy usage in the United States, and represents 30 percent of most buildings᾽ operating costs. Energy efficiency is typically mea-sured as a percent improvement (reduc-tion) in energy use as compared to an average building’s energy use in the past, or a calculated baseline building perfor-The Current BY JOHN V. MASSEY, PHD B mance (such as calculated by ASHRAE’s 90.1 standards). So what does that mean to building own-ers and operators? Th e U.S. Green Building Council’s LEED program requires a 14 per-cent energy improvement in new construc-tion and a seven percent improvement in remodels 1 . California State Law, Title 24 sets an overall goal of reducing greenhouse gases to 1990 levels by 2020, and also provides 20 May | June 2012 ■ Facilities Engineering Journal ■ www.AFE.org
Status & Trends In Energy-Efficient And Sustainable Facilities
John V. Massey
An overview of five high-performance buildings incorporating eco-friendly elements from design and construction through day-to-day operations. Find out how incorporating the right sustainability elements into your facility can lead to lower operating costs and a better environment<br /> <br /> Building-energy use accounts for approximately 40 percent of total energy usage in the United States, and represents 30 percent of most buildings. Operating costs. Energy efficiency is typically measured as a percent improvement (reduction) in energy use as compared to an average building’s energy use in the past, or a calculated baseline building performance (such as calculated by ASHRAE’s 90. 1 standards).<br /> <br /> So what does that mean to building owners and operators? The U.S. Green Building Council’s LEED program requires a 14 percent energy improvement in new construction and a seven percent improvement in remodels1. California State Law, Title 24 sets an overall goal of reducing greenhouse gases to 1990 levels by 2020, and also provides Prescriptive requirements for energy efficiency ratings, coefficients of performance and other measurements of efficiency.<br /> <br /> Energy efficiencies, however, are not the only parameter in modern highperformance buildings. Energy usage also directly correlates to greenhouse gas production and is extremely important from a sustainability perspective. The concepts of sustainability and green construction and operation have come to the forefront over the past 10 years. Today, it is necessary for facility managers to comply with state and federal energy and sustainability regulations and to become familiar with voluntary environmental and sustainability programs. In some areas, voluntary adherence to these programs (such as the LEED program) has become a de facto standard.<br /> <br /> How can your facility comply with energy-efficiency laws and voluntary programs, while remaining within your organization’s budget — or even saving money over the long term? This paper provides an evaluation of five modern buildings (see Table 1) that incorporated sustainability and energy efficiency in their design, construction and operation. The buildings were selected from a recent literature search to show various important features that are currently being employed in modern, highperformance green buildings. Three are modifications to existing buildings and two are new construction. A brief overview of what makes an energy-efficient, sustainable and “green” (environmentally conscious) facility is also included as a basis for the discussion.<br /> <br /> Sustainability is defined in overall terms by the Brundtland Report2 as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” Plans such as the LEED rating system and California state law require specific numerical goals for waste reduction, energy consumption, water usage, and other economic and environmental characteristics. Green Buildings, while initially more concerned with environmental issues, have morphed over the years to include energy efficiencies and sustainability issues. Due to this change, “sustainable” and “green” buildings have essentially come to mean the same thing.<br /> <br /> The field of sustainability is also not a static area. The federal and state requirements for sustainable design, construction and operation are continuing to change toward more restrictive requirements. Voluntary adherence to existing and proposed environmental and sustainable programs is also growing. Sustainable development, in both new construction and remodels, involves major considerations in sustainable design and construction, resource efficiency, waste reduction, water management and ecological design.Paramount among these considerations are health, comfort and energy efficiency.<br /> <br /> The buildings listed in Table 1 represent four outstanding blends of modern sustainable and energy efficient design, and one offers an example that is not economically justified. Table 2 summarizes the main features of the five buildings.<br /> <br /> Normand Maurice <br /> <br /> The Normand Maurice building is a Canadian government building of 168,900 square feet. The main features of the HVAC system are three HFC-based chillers, two gas-fired boilers, a geothermal heat exchanger on the surface utilizing 60, 450-foot-deep boreholes, sand-based thermal storage under 12-inch concrete slabs, extensive natural ventilation, and enthalpy wheels to preheat (or cool) incoming air. This system and the building envelope design produced large reductions in energy consumption (61 percent) and energy cost (55 percent) compared to the Canadian building standard. Sustainable features included:<br /> <br /> ■ Recycling of material (from old foundry that was demolished)<br /> ■ 100 percent recycle of steel<br /> ■ 82 percent recycle of wood<br /> ■ 92 percent recycle of brick<br /> ■ 75 percent of demo material diverted from landfill<br /> ■ 30 percent less potable water used / 50 percent less water to sewer<br /> ■ Rainwater and greywater treated and reused in toilets and urinals<br /> ■ Green roof with no irrigation<br /> ■ Envelope<br /> ■ Skylights - penetrating multiple levels<br /> ■ Shading<br /> ■ Maximizing daylighting and solar heating<br /> <br /> Health Clinic at the University of Massachusetts <br /> <br /> The University of Massachusetts healthcare renovation involved 14,000 square feet for a clinic requiring 100 percent outside air. Two steam-absorption chillers (installed in the 1960s) cross-connected to a centrifugal chiller (1980s), in poor condition, were available. Preliminary calculations Indicated an additional chiller was needed. Management challenged the calculations and asked for an energy audit. The audit found the chillers were long overdue for rebalancing. The rebalancing found that the cross-connection valve controls were incorrectly set, causing a flow deficiency. In turn, this caused the steam chillers to operate well below design values. Rebalancing and correcting provided the necessary cooling at a greatly reduced cost.<br /> <br /> The next design basis hot day confirmed the suitability of the cooling. The energy auditing and corrections yielded a three-month payback period from the more-efficient operations — demonstrating that investments in energy efficiency and sustainability can contribute to an organization’s bottom line far sooner than is generally perceived.<br /> <br /> Oak Ridge National Laboratory <br /> <br /> The Oak Ridge National Laboratory office building of 6,940 square feet was remodeled in 2009 for $660,000. Each room has a packaged heat pump. The remodel installed a 68MWh/y solar array, increased roof insulation (R-6 to R-16), T8 high-efficiency lights on occupancy sensors, a central printer, and low-power-mode systems on the computers. The remodel reduced the annual electrical load from 100 Mwh/yr to 65 Mwh/y. Hence, the solar array satisfies the load.<br /> <br /> Unfortunately, the cost savings associated with saving 100 Mwh/y is only $15,000 per year (at 0.15$/KWh). This yields a payback period of approximately 44 years at current rates. This long payback period would be substantially reduced only in the event of drastic energy increases, far greater than those predicted by even the most pessimistic energy experts.<br /> <br /> Holy Wisdom Monastery and Events Center The Holy Wisdom Monastery and Events Center (34,383 square feet) sustainability and energy-efficient features include:<br /> <br /> ■ High-performance envelope<br /> <br /> ■ R-30 roof<br /> <br /> ■ R 2.9 windows<br /> <br /> ■ Brick exterior<br /> <br /> ■ High-efficiency HVAC - Closed-loop ground-source heat pump<br /> <br /> ■ Minimum-lighting power density-85 percent daylighted<br /> <br /> ■ Low-flow fixtures - 1 gal/flush and waterless urinals<br /> <br /> ■ Private well<br /> <br /> ■ All gypsum, asphalt, steel and glass from recycled material Room-by-room<br /> temperature control, operable windows, multi-level dimmable light controls<br /> <br /> ■ No irrigation<br /> <br /> ■ Green roof on garage and maintenance building<br /> <br /> ■ Solar for 8 percent of electrical<br /> <br /> ■ In-floor hydronic heating<br /> <br /> ■ Bamboo floors<br /> <br /> ■ Natural ventilation in most rooms<br /> <br /> ■ Windows: wood casement<br /> <br /> ■ 23 percent transmittance (east, west and south)<br /> <br /> ■ 40 percent (north)<br /> <br /> ■ Solar gain of 0.23<br /> <br /> ■ T5 and T8 lighting<br /> <br /> These energy features resulted in an energy savings of 47.8 percent and cost savings of 53.7 percent compared to ASHRAE 90.1 standards.<br /> <br /> TIAA-CREF Headquarters <br /> <br /> The last building, TIAA-CREF headquarters, represents a good example of a making the best out of a forced retrofit. The building had two 1,000-ton chillers to handle a peak load of 1,400 tons. One chiller failed. They were both replaced with a 1,000-ton chiller, a 900- ton chiller, rooft op ice storage (600 ton hours), new advanced controls and new cooling towers. Ice is made at off-peak hours and used during peak hours. This shift ed the peak electrical consumption to the night (when electricity is less expensive) and significantly reduced demand. The retrofit reduced CO2 emissions by 6.1 million pounds/year and resulted in savings of $765,000/year. This produced a 25 percent rate of return on the project (roughly a four-year payback period).<br /> <br /> In summary, sustainability and energy efficiency go hand in hand and have risen to an important level in building and remodel design, construction and operation. Energyefficient design in new or remodel construction and energy audits in existing buildings can provide substantial savings. These savings can fund resource-efficient sustainable features.<br /> <br /> Many important sustainable features (water efficiency, run-off control, material recycle and waste minimization, daylighting, etc.) can be implemented with little additional cost and in some instances cost saving. When coupled with modern energy-efficient equipment and controls, the modern highperformance building can be considerably less expensive to operate and provide a large reduction in cost over the lifetime of the building.<br /> <br /> References: <br /> <br /> 1 Leadership in Energy and Environmental Design Program, U.S. Green Building Council, Washington, D.C. <br /> <br /> 2 Our Common Future, Brundtland Commission, United Nations, New York, NY (1987)<br /> <br /> John V. Massey, PhD is the chair of the Department of Engineering Technology of the California Maritime Academy, Vallejo, California.
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