Project Description

The installation of Infinite-R™ over ceiling tiles at the school resulted in a 29% reduction in propane use for heating savings in the first year of operation. This was however WITHOUT making any controls changes to specifically optimize for the PCM.

In the heating season, the first year of operation showed a calculated 29% reduction in propane use in the modular classroom addition (all on one propane service). This savings was calculated using heating degree hour comparisons and trend analysis. HOWEVER – this savings did not include any changes or optimization in controls for the PCM.

In January 2017, internet accessible controls were installed in the Non PCM & the PCM classrooms being monitored. Temperatures for heat set point were set at 72ºF during occupied time and setbacks were set at 62F on weekdays, with weekend setbacks of 62F. Temperature control was limited to (+/-) 1ºF.

Run time of HVAC fan for heating was monitored during a 30 day period and an astounding 56% reduction in fan use was measured!

Here are some snapshots that show the exact same time periods comparing the CONTROL vs INFINITE-R™ classroom.

(NOTE: To visually see differences in fan run time, compare the RED lines at bottom of each graph which denote frequency of fan operation)

CONTROL / NON PCM Classroom

Infinite-R™ Classroom

Heating Performance

The graph below shows a snapshot of performance of two modular classrooms tested side by side WITH and WITHOUT Infinite-R™. When both classrooms are controlled the same, it's easy to see that during setback mode overnight, the room with the phase change material does not drop anywhere near as significantly as the room without the PCM.

Cooling Performance

Again, similar comparison of identical modular classrooms during late June show that by running a short cycle of cooling very early in the morning (4am to 6am), the room with PCM's stores mostly free ventilation cooling to help mitigate any need for cooling as the day progresses.

The result is a max temperature of around 73ºF in the PCM room and routine temps above 78ºF without PCM over the course of summer.

Project Description:

In December 2015 a total of 11,000sf of Infinite-R™ was installed in one wing of the middle school over existing suspended ceiling tiles. The results have been very interesting to date.

  • Melting PCM in winter above ceiling from heat loss in un-insulated ductwork
  • Sustaining temperatures overnight with no heat use (never really dropping below 67ºF), and often sustaining above 65ºF (setback temp) from Friday afternoon all the way to Sunday afternoon on weekends!
  • Absorbs heat during hot days to mitigate use of air conditioning in areas with A/C installed.
  • More than 50% reduction in temperature swing when comparing two modular classrooms with vs without PCM!

Details:

Location: Newton, NH

Install Date: 2015

Quantity of PCM: 11,000sf

Estimated Savings: 20% – 30%

Investment Return: 5 yrs (Heat only) 3 to 4 Yrs (Cooling included)

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