A Lesson Plan For Sustainability
The Medical University of South Carolina implemented broad energy efficiency im-provements without incurring capital costs.
By John F. Plack Jr., P.E.
June 1, 2013
Today, many state institutions of higher learning and healthcare facilities face reduced budgets, aging infrastructure, and rising energy costs. According to the EPA, colleges and universities spend close to $2 billion each year on energy. These institutions are seeking innovative ways to renew facilities, improve energy efficiency, and reduce energy costs. One option gaining some renewed momentum is the Energy Savings Performance Contract (EPSC).
An ESPC guarantees a minimum level of energy savings over the term of the contract, effectively allowing a facility to pay for im-provements out of their existing operating budget. This budget-neutral approach allows the facility to pay for energy upgrades through a portion of the cost savings resulting from these improvements over a set term. At the end of the contract, the facility owns all of the improvements and receives all of the continuing savings.
The Medical University of South Carolina (MUSC) is a teaching facility, medical research facility, and regional healthcare provider for the Charleston area. Both a public institution of higher learning and a health care facility, it comprises hospital facilities, classrooms, and laboratories. The medical university provides an environment for learning and discovery through education of health care professionals and biomedical scientists, research in the health sciences, and provision of comprehensive health care. While striving to provide an excellent, collaborative education for its students, MUSC was facing reduced state funding, aging infrastructure, and increasing energy costs. These challenges contributed to MUSC’s decision to implement infrastructure upgrades through an ESPC that would provide energy savings.
Given that hospitals and healthcare facilities typically use more than twice the energy per sq ft as office buildings, MUSC was an excellent candidate for energy efficiency upgrades and retrofits. After a competitive bid process, MUSC partnered with Ameresco, an energy efficiency and renewable energy company, on their budget-neutral energy efficiency project. Ameresco’s technical team began with a detailed energy audit of the energy-consuming systems of the buildings. Once the energy audit was completed, MUSC received a solution for the energy project, accompanied by assurance that the project would be completed without disruption to health care operations.
The $14.5 million project included the installation of motors and drives, lighting upgrades, new water fixtures and water conservation retrofits, other mechanical upgrades, and controls. The scope of work also included new AHUs, distributed units, and chillers.
Let’s do rounds to review some of the improvements.
MOTORS & DRIVES
Existing domestic water pumps across campus wasted energy because their motors operated at a constant speed and many were oversized. New, properly sized domestic water pumps equipped with premium-efficiency motors and integral VSDs were installed to reduce energy consumption and operating costs. Additionally, the chilled water pumps at the Clinical Science Building were retrofitted with premium-efficiency motors and VSDs.
Ameresco replaced 2,117 fixtures; 49,348 lamps; and 23,745 ballasts. The majority of these were replacing outdated fluorescent lamps and ballasts with energy-efficient 28-watt T8 lamps and electronic ballasts. These improvements to the lighting system saved significant energy and also improved the overall color rendering and consistency of the lighting while standardizing the lamp types for maintenance staff. The energy efficiency measure resulted in savings exceeding 41% of current lighting energy consumption.
WATER FIXTURE REPLACEMENT AND RETROFITS
Existing water fixtures were replaced or retrofitted with more efficient fixtures/equipment. These replacements and retrofits included domestic plumbing fixtures, a new partial recycling system for the reverse osmosis system, replacement of the energy inefficient vacuums on the sterilizers with pumps or recirculating systems, new temperature control devices, flow restrictors, and other measures. These upgrades resulted in decreased water consumption and energy costs.
The ventilation requirements of hospital and research facilities result in the use of 100% OA, which must be cooled and dehumidified for indoor use and proper air quality. Because of the high humidity of the Charleston climate, the AHUs at MUSC produced large quantities of condensate water. This condensate is a clean, cool source of water for non-potable use. The condensate from many of the large AHUs on campus is now collected and reused as makeup water for cooling towers. Installation of this system recovers over 6.8 million gal of water annually.
IMPLEMENTATION OF MECHANICAL UPGRADES AND CONTROLS
The improved overall steam system resulted in steam consumption reduction. In addition, malfunctioning equipment was replaced and steam traps, old boilers, and sensors were repaired or replaced. Boiler stack economizers were added to various boilers and energy saving control strategies were implemented in several buildings through the existing EMS. This system was also expanded to include newer Network Automation Engine (NAE) extended architecture at Harbor View Office Tower.
The existing laboratory fume hoods operated at higher airflows than did currently available equipment. The airflow to the fume hoods must be introduced to the building as costly-to-condition outside air. The laboratory fume hoods an energy-efficient conversion. The design of these fumes hoods more effectively removes contaminants from the workspace with lower airflow volumes, resulting in decreased energy consumption and cost.
In many of the buildings, the AHUs and chillers were upgraded, also resulting in decreased energy consumption. At the Children’s Hospital, the two 780-ton chillers on the ninth floor were replaced with a new 1,300-ton variable-speed centrifugal chiller located in the 10th-floor chiller penthouse. At the Clinical Science Building, one of the three 300-ton chillers was replaced with a new 580-ton variable-speed tri-rotary screw chiller to increase efficiency, capacity, and redundancy.
For the Rutledge Tower Building, one of the larger upgrades included modifying the chilled water plant to preferentially operate the electric chillers and only use the absorption chiller as a backup. In addition, a chilled water flow meter and temperature sensor in the piping connecting the Main Hospital to the Storm Eye Institute building was installed, and steam submeters were installed to measure where steam was supplied from the main boiler plant.
As an added benefit, these improvements allowed MUSC to increase the energy infrastructure capacity for the growing campus, improve reliability and control, improve IAQ, and significantly cut energy and operational costs. These measures reduced MUSC’s carbon footprint and helped them become an environmental leader focused on sustainability.
Higher Education and Healthcare
The modernization of campus energy systems presents significant opportunities for higher education facilities to attract new students and reduce utility, operation, and maintenance costs. Most institutes of higher education must deal with a patchwork of old and new equipment, varying levels of operational efficiency, and the lack of a campus energy management system to control overall energy use. For state schools, stricter energy consumption rules can stress budgets as funds are sought for mandated upgrades.
With an Energy Savings Performance Contract (ESPC), higher education institutions can get the energy infrastructure upgrades they need now and stabilize ongoing utility costs to develop a source of capital in the future. Ameresco can modernize a single facility or provide comprehensive campus-wide energy management systems, built from best-in-class energy-efficient and renewable energy solutions, financed entirely with capital collected from campus energy conservation. Renewable energy systems lower energy costs, reduce reliance on fossil fuel and the power grid, increase energy security, and provide additional benefits for student recruitment. A behavior modification program that delivers life lessons for embracing efficiency and conservation measures can also be implemented.
Campus renewable energy and energy conservation policies play a role in the ability of schools to attract and recruit undergraduate and graduate students. Increasing awareness of environmental responsibilities and the need for sustainable development at the primary school level has created a generation of students hard-wired to consider environmental impact as part of their decisionmaking.
Energy efficiency programs can be developed with higher education institutions that encourage energy conservation through student and staff behavior modification, such as reducing lighting, electricity, and water use. The implementation of these renewable energy systems and sustainability initiatives serve as an institution’s ongoing commitment to the concerns of its students. Once a top-of-mind issue relegated to recruitment in the sciences, campus energy use is now an important consideration for students across every academic discipline. Schools that are leaders in sustainability initiatives, including renewable energy use and energy conservation, have an advantage in recruitment, as well as an energy use approach that delivers greater value for each energy dollar spent.
Hospital energy costs can be twice as high as those for office buildings, and healthcare facilities are limited in the amount of energy costs they can pass on to patients. Volatile energy prices jeopardize budgets, and the need for guaranteed energy delivery to life support systems presents challenges to modernization plans.
Healthcare facility management can be improved by retrofitting existing healthcare facilities for greater efficiency, or by developing a comprehensive energy management system utilizing renewable energy sources. Hospital energy savings from these projects average 30% annually, money that can be used for facility upgrades, new equipment, or even additional staff.
Elsewhere In Health Care
Recent and relevant in the ES archives at www.esmagazine.com ...
Modular Central Utility Plants: A Different Approach
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Energy-Efficient Dehumidification In Health Care Facilities
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Retrofitting Primary Chilled Water Pumps With VFDs
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Critical Care: IAQ For Isolation
By John Bilotta, P.E., LEED® AP and Thomas J. Thomas Ford, LEED AP
Based in Charlotte, NC, Plack manages the day-to-day business of Ameresco’s southeastern Project Development Group, which comprises developers, engi-neers, and analysts. He is responsible for providing each customer with top-quality energy and renewable energy solutions that meet both their current and long-term needs. Plack has over 15 years of experience in the energy industry and has developed projects for many federal, state, local government, and higher education entities.