Energy Accounting & Portfolio Manager
Benefits of Energy Accounting
Tracking building energy use data and submitting it to PM should not be seen as just an exercise to document compliance with state mandates. It can also help organizations better understand how their buildings and other facilities use energy and identify how to reduce energy use by cutting waste and improving efficiency, often improving occupant comfort and indoor air quality in the process.
With limited financial resources, it is important for agencies to focus their efforts where they are most likely to generate cost-effective reductions in energy use intensity. A good target for efficiency improvement projects would be one where energy use is high and energy use intensity is also high (i.e. large and inefficient buildings). However, there are certainly other characteristics to consider when selecting targets, such as age of facilities, dates of the most recent major renovation, and expectations for continuing occupancy. If a building is due for a major renovation for any reason, it may be helpful to have a graph showing details of energy use in the past few years to inform the design process.
The WSU Energy Program can provide observations and analysis of energy use trends and anomalies to help guide the exploration of opportunities for efficiency improvement. For staff familiar with the properties and their operation, the explanation may be immediately obvious in some cases, but others may be surprising or alarming and generate the need for further exploration. They could indicate equipment failures or a utility billing error. Overall, it is most important to focus on observations of recent variations rather than on what happened years ago, but multi-year graphs of energy use can also be useful. The observations are also intended to encourage agency staff to develop more of an interest and expertise in reviewing energy use graphs that are available from PM and spotting trends and anomalies in graphs, EUIs, or ENERGY STAR scores regularly, or as appropriate for budget and project development schedules, rather than just when the WSU Energy Program provides reports annually or semi-annually.
It may also be worthwhile to investigate the construction, equipment, and operation of the most energy efficient properties to try to learn what characteristics are responsible for their great performance and which of those could be applied to other similar but less efficient properties.
Typical Energy Use Variations
It is useful to identify and target the largest energy using facilities for the largest potential impact on portfolio energy use. It is useful to examine variations in energy use over time to see the impact of changes in occupancy and/or operation, as well as implementation of energy conservation measures.
For most commercial buildings, heating is currently provided by natural gas, due to its low cost. Therefore variations in natural gas energy use is highly seasonal. The natural gas used in the middle of the summer typically (but not always) indicates water heating. Electricity usage is typically only slightly seasonal in annual variation, reflecting the increase in lighting during the darker winter months.