Wake County Middle Schools Energy Analysis
The following information summarizes a comparison of the energy performance in all Wake County middle schools for which adequate records were available during the last two years (95-96 and 96-97). The majority of the schools have typical school year schedules with only West Lake and Durant being year round middle schools. Durant is the only extensively daylit middle school.
Because of the extended use required in the year round schools it is difficult to fairly compare these two schools to the remaining schools. Comparison is also made more difficult because the schools have varying levels of space utilization and exterior fighting, and nighttime and/or community use. Another significant factor was that all of the schools listed with the exception of Durant did not come into compliance with the new ASHRAE Standard 62-91 which dictates greatly enhanced ventilation rates. For example, the fresh air requirements in Durant, even utilizing heat exchangers, were still directly responsible for over one quarter of the entire building energy consumption. However, despite the additional ventilation incorporated into Durant, West Lake, the other year round school, used 24% more energy than Durant. It is estimated that had West Lake meet the new ASHRAE standards, West Lake would have used 55% more energy (or Durant's energy consumption would have been 65% of West Lake's).
Additionally, despite Durant being used over two months a year longer each year and having a higher than typical space utilization and nighttime and/or community use, the energy consumption of the average, non-year round middle school in the county was 30% more than Durant. Had these schools complied with the ASHRAE standard, the average school would have used 63% more energy (or Durant's energy consumption would had been approximately 61 % of West Lake's).
Size Cost/Square Foot Jul 95-Jun 96 Jul 96-Jun 97 Year Round (12 months) Schools Only Durant 149,249 .84 .80 West Lake 137,101 1.061 .971 West Lake Mtg ASHRAE 1.333 1.213 Typical School Year (Non-Year Around) Average of 13 Schools 139,048 1.102 1.032 Average Meeting ASHRAE 139,048 1.383 1.293
1 all middle schools except Durant were pre-94 and before new ASHRAE ventilation standards were required.
2 in addition to these middle schools not complying with new ventilation requirements, they possessed varying levels of space utilization, exterior lighting, and nighttime and/or community use.
3 reflects an estimate of energy consumption had the schools been designed with the new ASHRAE ventilation requirements (assumed 25% greater energy use)