A building's main meter interval data is useful for profiling energy time-of-use ("TOU") that tells us when energy is consumed; By hour of day, day of week and seasons of the year.

With some statistical innovations that look at the changes in consecutive metered loads, we can disaggregate the loads in a different way to identify the large discrete loads that typically have the most impact on the TOU profiles and the facility's utility bill. With this, we can start to chip away at a better understanding of the significant cooling and heating loads in a typical commercial space.

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UMass Dartmouth completed a large and expensive campus-wide ESCO performance contract but lacked the ability to quantify the cost of savings that were not achieved or being maintained. The University also had no quick and efficient way to evaluate millions of building automation system (BAS) data points and thousands of alarms.

AEI delivered a set of discoveries worth $150,000 in annual operating savings from electricity usage with the potential for another $190,000 in steam savings.

Hostelling International Boston is a 485-bed hostel with over 2,000 heating and cooling complaints in the two years after receiving LEED Silver designation in 2012. The building uses nearly three times the energy of the DOE average for a small hotel in this region of the country.

AEI was engaged by the prime contractor to study the sequence of operations and discover opportunities for peak demand mitigation at two separate campuses of a large high school system in Massachusetts, with a combined total of 783,000ft² and 3,300 students. Peak demands during the summer cooling season—normally expected to be an unoccupied time of the year—showed the largest variability in electric demand. The unpredictability of the demands made it difficult to consider any demand response initiatives until the nature of the swings could be determined.

Many towns in MA have several facilities on utility rate schedules where 70% or more of the bill is composed of “demand charges” that are based on the highest demand used by the customer in the billing period. In the case of the Carlisle Public School, each kW of peak demand in the period costs $19.19 and with typical peaks exceeding 250kW, a 10% reduction is worth over $5,500 annually. If rumored increases in demand charges come true in 2016 and beyond, the risk of doing nothing could cost an extra $5,000 to $15,000 per year at the school alone.

Many towns in MA have several facilities on utility rate schedules where 70% or more of the bill is composed of “demand charges” that are based on the highest demand used by the customer in the billing period. In the case of the Carlisle Public School, each kW of peak demand in the period costs $19.19 and with typical peaks exceeding 250kW, a 10% reduction is worth over $5,500 annually. If rumored increases in demand charges come true in 2016 and beyond, the risk of doing nothing could cost an extra $5,000 to $15,000 per year at the school alone.

AEI reviewed classroom ventilation for a New England school when classes resumed in the fall of 2015. Most classrooms in the school maintained CO₂ levels below the 1000ppm setpoint, but one classroom recorded levels above 1500ppm two to three times per week. Even though this level is not considered a direct health risk, it does indicate the classroom may be under-ventilated. The CO₂ levels in this classroom were frequently higher than the classroom setpoint of 1000ppm and outside the 1000 to 1200 ppm range most facilities try to attain. Even though increasing the ventilation rate would result in increased costs to condition the air, it was necessary to identify the cause of the high CO₂ levels.

The Town of Carlisle’s Gleason Library is a recently renovated 11,000ft² facility and is a relatively small piece of the Town’s energy footprint. But like many facilities on “demand charge” utility rate schedules, 60% of its monthly bill is based on the highest demand used by the customer in the billing period.