Using Technology for Building and Cost Control
- By Christian Javorski
- December 1st, 2009
Nearly 3 million kilowatt-hours (kwh) of electric energy are anticipated to be saved at Casa Grande (Ariz.) Elementary School District from a recently implemented energy management and awareness program.
The district engaged an energy consultant early in 2008 to perform an energy audit to identify potential areas where the district could reduce their energy consumption. Based upon that energy audit, the district has implemented a new energy management system (EMS), lighting retrofits, HVAC efficiency upgrades and a student-body-and-staff energy awareness program.
The first phase of the energy program includes a new EMS at two elementary schools and one middle school that replaces the existing pneumatic and electronic thermostats and controls. This allows the district to better schedule the schools’ energy consumption and trouble-shoot maintenance issues.
The second phase is a comprehensive lighting retrofit that replaces older lighting with higher-efficiency T-12 fluorescent lighting with T-8 ballasts and lamps throughout. With higher efficiency ballasts, the district was able to de-lamp multiple areas from 4-lamp to 3-lamp ballasts. This de-lamping provides additional electrical savings and utility rebates. According to Frank Corder, the district’s construction manager, “APS utility rebates enabled the district to expand the scope and fund the project under budget.” Additionally, the district’s staff recognizes an improvement in the overall quality of the light produced from the newly installed lighting.
The next phase was an upgrade of old cabinet style fan coils at the Casa Grand Middle School campus that were at the end of their useful lives with a new low-horsepower, ducted fan coil system with demand ventilation control using CO2 sensors. The efficient operation of this innovative design is not only saving energy but also providing for a much quieter and comfortable learning environment. Previously, this 60-room campus used two chillers that struggled to keep up with demand for cooling. Now, with these more efficient fan coils, along with new piping and outside air controls with CO2 sensors, the demand has been significantly reduced and currently only one chiller is needed to sustain the required cooling load.
The district has formed an energy conservation committee that raises energy use awareness and encourages behavioral changes by both district employees and students. As one of the committee’s first actions, heating and cooling set point standards have been established and submitted to the district’s Governing Board. The board recently approved the standards and the new set points are already in place conserving energy.
Another phase of the energy program includes networking the existing energy management systems and adding controls to buildings that previously were without them. As a result, the entire district can be scheduled with the set points determined by the energy conservation committee and newly adopted district policy. Andy Seaver, director of Facilities, has been working diligently creating separate schedules and set points in various campuses based upon usage of the area for even more energy savings. If an area is not occupied, setbacks are programmed accordingly and unoccupied settings are placed even higher on weekends and holidays. Zone scheduling in some areas has allowed for offsets in startup times to avoid costly peak demand charges.
Moreover, Seaver has implemented energy management routines with the new EMS that ties everything together. To date, the district has saved over 2.5 million kWh ($ 250,000.00) with projections this first year of over 3 million kWh. This savings also directly reduces green house gas emissions and equates to a 1,757-metric-ton reduction in CO2 that is equal to the green house gas emissions of taking 322 vehicles off the roads for a year. With more programming being completed, the district will be able to reset equipment to reduce demand charges, integrate occupancy sensors to setback temperatures and control lighting, control outside air by incorporating CO2 sensors and slow pumps and fans during times of reduced demand. The district’s conservation committee is also encouraging behavioral changes by modifying night cleaning efforts to a team approach that will allow current night setbacks to be turned completely off as each wing is completed.
As a comparison, another large district in the state with approximately 42 campuses has recently claimed a seven-percent savings over the past 12 months, reducing their Kwh by an impressive 3.5 million. Casa Grande Elementary School District, with its 12 campuses, in its first year of energy management, has saved 2.5 million kWh in the past nine month period compared to this time last year. This success is a direct result of highly collaborative and concerted effort to implement refined energy management strategies by all participants in the district, including the energy conservation committee, outside energy consultants, key individuals from each campus and the governing board. The district’s focus on saving energy along with electrical and HVAC upgrades have allowed the district to realize more than 20 percent savings in its energy consumption.
Due to the impressive savings and success of the district’s focus on energy efficiency, Casa Grande Elementary School District plans to continue implementing energy savings strategies and innovative technologies as they move forward. Corder has been integral in all of the upgrades to date and is continuing to implement many of the proven energy savings strategies into a new elementary school the district is planning to build next year. As energy costs continue to rise, the use of taxpayer monies in capital projects that both improve the learning environment and reduce operating costs is a wise investment.
Christian Javorski is the owner of a performance-based energy consulting company, Tarian Solutions, that specializes in enhancing building energy performance through mechanical, electrical, energy management and behavioral modifications.