NEEP Notes: Best Practices in Energy Efficiency Programs in the Northeast

Best practices in energy efficiency programs in the Northeast

NSTAR's Construction Solutions Program featuring Ashland High School (Mass).

NSTAR is the largest Massachusetts-based, investor-owned electric and gas utility. NSTAR transmits and delivers electricity and gas to 1.1 million electric customers in 81 communities and 245,000 gas customers in 51 communities. NSTAR employs more than 3,300 employees in its regulated business.

NSTAR Construction Solutions program targets time dependent opportunities for the installation of energy-efficient equipment in the new construction, renovation, remodeling, and failed equipment markets. In addressing these markets, the program’s goal is to make energy efficiency options an integral part of the design process by influencing architects, engineers and the building design community to incorporate energy-efficient design, strategies and equipment in the early design phase, thereby raising the energy efficiency of normal building practice.

Construction Solutions offers commercial and industrial customers the opportunity to receive financial incentives, technical assistance and commissioning services for their projects. The program encourages customers, developers, design professionals and equipment vendors to select high efficiency equipment and incorporate energy efficient designs for buildings and electrical and mechanical systems.

Ashland School System
All NSTAR customers served under a non-residential rate are eligible to participate in the Construction Solutions program. Among those qualified for program services is the school system in the town of Ashland, Massachusetts. Ashland is located in the Metrowest area of Massachusetts, midway between Boston and Worcester. It is a predominantly residential community with a population of approximately 15,000.

Faced with a steady increase in town growth and a historically low level of capital investment in schools, the Ashland school system commissioned a school expansion needs assessment in 2006. The town concluded that construction of a new high school would be necessary to accommodate the growing student population and that the project could be completed in a cost effective manner with assistance from local utility programs.

Need for Efficiency Improvements

Upon hearing of the new school building project in Ashland, NSTAR contacted the customer to discuss the opportunities available through the Construction Solutions program.

In addition to increasing the size of the high school to accommodate more students, the objectives in constructing the new building were to:

Decrease energy costs

Maximize efficiency

Minimize cost of re-design

Improve environment for students

Employing a comprehensive design approach, NSTAR worked with the town of Ashland to construct a high performance green school. Green schools incorporate various energy efficiency measures and environmental considerations to result in buildings that cost less to operate and maintain and provide healthy, productive learning environments.

The new Ashland High School is now a state-of-the-art, 200,000 square foot facility with an estimated population of 900 students.

“Comprehensive Design Approach can be viewed as the best practice when considering several different options of program implementation. Specifically, it takes into account the interactive effects of multiple energy conservation measures on a building. As a result, the facility achieves a more sustainable design and the customer not only earns enhanced incentives for participation, but also realizes lasting energy benefits long after the building is completed.”

- Roseann Brusco, Program Manager, NSTAR Electric and Gas

Energy Efficiency Measures Implemented

NSTAR’s Construction Solutions program provides financial and technical assistance to implement energy and money saving measures in categories such as lighting, heating and cooling; motors and variable speed drives, compressed air, and other custom measures.

Along with the incorporation of renewable energy sources and the integration of local construction materials and artistry, the following energy efficiency measures were installed in the new Ashland High School as a result of their participation in the Construction Solutions program:

Electric Energy Efficiency:

Occupancy sensors: Placed in appropriate areas in the new Ashland High School, occupancy sensors control lighting, heating and cooling in intermittently occupied areas to reduce energy use and save money.

Daylighting: Studies indicate that lighting classrooms with natural, indirect light can enhance student performance. Designing rooms to take advantage of daylight can also save money. Properly designed systems can substantially reduce the need for electric lighting, which can account for 35 to 50 percent of a school's electrical energy consumption. An added benefit is that waste heat from the lighting system is also reduced, which in turn reduces demand on the school's cooling equipment by up to 10 to 20 percent. Ashland High School uses daylighting controls throughout its office and classroom space.

High efficiency lighting: Highly efficient lighting systems reduce energy costs and optimize lighting quality to improve productivity in students and staff.

Water-cooled chiller and open cooling tower: These systems are more efficient than standard air-cooled chillers or closed cooling towers, thereby reducing energy and maintenance costs.

Occupancy-based control of Variable Air Volume units in classrooms: Variable air volume controls regulate the quantity of air supplied to a given space based on the temperature in that space. As a result, money and energy are saved due to a reduced flow of air in unoccupied spaces.

Variable Frequency Drives (VFD) for hot water pumps and secondary chilled water pumps: VFDs control electric motor speed and match the energy output of the load it serves.

Gas Energy Efficiency

High efficiency gas fueled condensing hot water boilers: This equipment converts more fuel into heat than standard models and recovers as much waste heat as possible to save energy and money.

CO2 sensor-based, demand-controlled ventilation: This system controls ventilation levels based on occupancy. It saves energy and money by limiting the use of the system to when it is needed.

Heat recovery system: Heat recovery devices reclaim energy from exhaust air flows and use heat exchangers to heat or cool incoming air. As a result 60 to 80 percent of conditioned air that would be lost in standard systems is recovered.

Incentives

NSTAR’s Construction Solutions program offers cost sharing for engineering services as well as design and commissioning services. Program participants can receive rebates of up to 90 percent of the incremental cost differential for comprehensive energy efficiency design. Rebates of up to 75 percent of the incremental cost differential between standard base line and high efficiency equipment are also available.

Ashland High School received a $272,156 incentive for the electric efficiency measures implemented under the Construction Solutions program. NSTAR also provided a $60,000 incentive for the gas efficiency measures incorporated in the project.

Savings

As a result of Ashland’s participation in NSTAR’s Construction Solutions program the new high school building will save 411,765 kilowatts of electricity each year, or the equivalent of an annual energy cost savings of $47,000. The school will also realize natural gas savings of 39,826 therms per year, or the equivalent of $44,000 in annual energy cost savings.

“Ashland High School is a ‘Green School’ success. Participating in the Massachusetts Collaborative for High Performance Schools and working with NSTAR in the design and completion of the new high school has been a very rewarding experience for everyone involved in the project. Not only do we own and operate a beautiful, energy efficient facility, we are saving money and resources in the process with limited impact on the environment. The savings to the town in reduced energy consumption, along with receiving rebates and incentives has allowed the town to stretch their ever-shrinking budget just a bit further. The extra time and energy in the design phase of the building has proven to be invaluable. NSTAR was extremely supportive during this phase, answering a battery of questions, providing us with recommendations and information and assisting us through each step of our planning and implementation. The end result is that Ashland High School is an aesthetically pleasing, high tech, energy efficient building that every member of the community can utilize and take great pride in.”

- Kevin Johnson, Supervisor of Buildings and Grounds, Ashland Public Schools

Interested in submitting a case study for NEEP Notes? Please contact Catherine Stanley for more information.