The building was able to reduce its electrical usage for these pumps by over $2,500 per month as well as enabling a significant reduction in wear on the pumps.
Many clients who operate campuses of buildings have the option of dual heat sources for their buildings. Typically, these include a central heating plant, in addition to local boilers within the buildings. The configuration and programming of the controls to efficiently operate both heating systems together can be complex, and certain aspects of the control are often programmed inefficiently. This was the case for this higher education campus client, located in a cold part of Canada. Their central steam plant provides reliable heating energy to the whole campus, but is not used all year round, especially not in shoulder seasons when the heating load is smaller and the buildings can use their more efficient and less costly local boilers, which tend to be sized to handle smaller loads. It is important with these dynamically adjusting heating systems that all components within the buildings and plant act together in unison, which often is not the case.
During this project, CopperTree’s Kaizen FDD analytics platform was used to analyze the complex operation of the building’s heating systems. It was observed that the hot water pumps used to transport hot water from the heat exchangers were not always properly interlocked with the heating supply being used. In other words, even when the heating source was not steam, and the steam valves were closed, the heating pumps were running. This is a waste of energy since the pumps are not at all required when the steam valves are closed. Further analysis also showed that the heating pump staging could be improved when there was low demand by eliminating the second pump and running only one pump until additional flow was required to justify staging on a second pump.
CopperTree recommended improved controls sequences to maximize the efficiency of the heating systems. Once these recommendations were taken, the building was able to reduce its electrical usage for these pumps by over $2,500 per year as well as enabling a significant reduction in wear on the pumps by running them for far fewer hours each year.
