Advanced Retrofit of Modular Classroom

There are nearly 80,000 relocatable classrooms in use in K-12 public schools within the state of California. These classrooms serve a critical need in California schools. They are quickly constructed and placed at particular school sites where there is a specific need. In addition, they can be removed and/or relocated when that need no longer exists or that need is experienced at another location. Their flexible format allows school districts to react to fluctuating enrollment levels and create classroom space appropriate to the changing demographics of their specific school enrollment needs and remain in place for a long duration or sometimes permanently due to increasing enrollments at the schools . Some schools consist entirely of these relocatable classrooms. Southern California Edison’s (SCE) Emerging Technology (ET) program chose to evaluate the potential energy savings and determine the cost-effectiveness associated with different levels of retrofits using energy-efficient technologies that are implemented within a relocatable classroom building structure. The test site selected for this project is an institutional facility located in Irvine, CA. Two classrooms were selected that share an entire relocatable structure at the site. These classrooms are almost exact replicas of each other with the same square footage, equipment, and similar fenestration. This field study was broken into two phases. The emphasis of Phase 1 was to identify and recommend what retrofit upgrades should be implemented within the two classrooms. Phase 2 dealt with the installation, monitoring, data collection, analysis, and report performance of the technologies implemented. This project aims to inform relocatable classroom managers of the most cost effective and viable energy efficiency options for the facilities they manage based on its location, so they could implement those technologies as a package to achieve deep energy savings and possibly site Zero-Net Energy (ZNE). The retrofit technologies were recommended by comparing the classrooms’ existing condition to currently available advanced technologies. The two classrooms were inspected with the intentions of implementing technologies that would comply with or exceed the Collaborative for High Performance Schools (CHPS) criteria since relocatable classrooms are not subject to California Title-24 building codes. One of the classrooms received energy efficient technology upgrades to achieve highest possible level of efficiency and served as the control classroom. Second classroom received same energy efficient technology upgrades plus the PV sized for the new reduced demand of the classroom to achieve site ZNE scenario. The following technologies were implemented and evaluated as part of this project: 1. Low-E Dual Pane Windows 2. LED Lighting with Controls (occupant and daylight sensors, dimming capability) 3. High Efficiency Heating, Ventilation and Air Conditioning (HVAC) Units with Economizers 4. Smart Thermostats (programmable, remotely accessible as well as DR capable) 5. Photovoltaic (PV) System Energy storage was not considered for this project as it was not a cost effective option at the time of the evaluation. In addition, adding an energy storage system required permanent install on an otherwise temporary structure i.e. relocatable classroom. Site energy data was collected using an energy monitoring system and was used to inform and calibrate an eQuest energy simulation model of the classrooms. HVAC, lighting, and miscellaneous plug load demands were obtained from the data monitoring system in order to adjust the eQuest model to accurately reflect each given classroom. Space, supply, and return temperature data was collected in order to verify proper operation of the HVAC system and thermostats. The model assumed a “typical” operating profile and was able to eliminate abnormalities such as occupants raising or lowering the heating set-points, and construction or maintenance periods.