Owners and managers of large non-residential buildings usually pay around 15–30% of their (ever-increasing) electricity bills for network ‘capacity’ in most markets. But peak demand savings are rarely a focus for management. Why? Until recently there have been a few good reasons – mostly related to difficulty predicting peak demand events in advance and the negative impact that load shedding can have on the comfort of building occupants. Now that the results of our recent summer peak demand forewarning study are in, however, we can say with confidence that network capacity is a manageable resource and the potential for savings is very large.
Backstory: why did the study come about? Last August, we brought together 40 of Australia’s leading commercial building owners and managers at a forum to look at ways to achieve a more resilient and reliable electricity grid by actively managing peak demand. It was an inspiring event, with participants representing around 3% of Australia’s national energy consumption and around 7% of the demand on the national electricity market. At the end of it we had two main questions to answer during the 2017/18 (Australian) summer:
- What strategies can operators implement to achieve meaningful demand reductions during peak times without compromising building performance /services?
- Can peak demand events be reliably forecasts well in advance (i.e. not just “most” of the time, but “all” of the time)?
Although we had been doing R&D on advanced demand modelling and feedback methodologies for the previous two years (and found indications of success), that work had mostly raised more complex challenges and required us to develop ever-more sophisticated energy modelling technology to handle “unprecedented” and “extreme” situations, i.e. conditions that most statisticians and data scientists try to avoid!
After working through the winter and spring developing new modelling advances we were ready to deploy the three components of our peak demand forewarning system:
- a pre-summer-peak engagement program designed to raise operators’ awareness about peak demand and strategies that can be adopted to shift or shed demand at peak times;
- a suite of automated ‘forewarning’ email messages sent to each building’s operator(s) every morning for up to five days leading up to a forecast peak event; and
- an automated “summary” email message issued the day after each peak event quantifying the outcomes of the operator’s actions (if any) to close the feedback loop.
In total, 71 buildings were involved (23 in Melbourne and 48 in Sydney) and it was found by comparing the buildings’ 2017/18 maximum demand with 2016/17, and normalizing for weather conditions, that their peak demand reduced on average by 3W/m2 (0.28 W/ft2). The reduction in operating costs was about $0.50/m2 (5¢/ft2) on average. For a typical 25,000m2 (270,000ft2) building this corresponded to a saving of over $12,000 – typically for just a few hours work! The results for the Sydney buildings are illustrated in the graph.
We collected lots of interesting feedback and analyzed each building’s results in some detail. If you’d like to know more about the methods, what worked, and what didn’t, please look out for the ACEEE paper or contact us directly. And if you want to apply some of these techniques to cut operating costs in your building(s), better utilize network infrastructure, or help improve grid stability / resiliency from effective demand management (or all the above!), please get in touch. We’d love to help!