Focus On Demand Can Help Cut HVAC Energy Costs
Another step taken by McGill to cut HVAC energy costs was a focus on managing demand. During the summer of 2013, the team focused on managing demand to reduce peak power demand charges and to only run the smallest steam boiler on campus.
During the summer of 2013, the team focused on managing demand to reduce peak power demand charges and to only run the smallest steam boiler on campus. On average, the monthly peak power demand during the summer is 8 MW higher than during the winter, resulting in an extra $80,000 on the monthly utility bill. During the hottest, most humid days of this summer, building operations monitored the power demand of the main electrical entrance so as to minimize peak demand.
Measures were also taken to minimize steam demand so as to run the small 20,000 lb./h. boiler instead of the 100,000 lb./h. boilers. Keeping demand low during daytime has been easy, but managing spikes in steam demand early in the morning during cool summer days has proven challenging. Nevertheless, running the small boiler for most of the summer has generated savings in the order of 40 percent of the baseline consumption for these months (June through September). To help this endeavor, a graduate student developed a steam forecasting model based on data from the monitoring software as well as a steam generation optimization tool. These solutions will be used to inform powerhouse operators of upcoming conditions and optimal configuration of boilers to meet forecasted demand.
A number of lessons were learned from the deployment of EMIS. First, hardware and software don't waive the need for brainpower and interconnectivity. Second, the learning curve to digest and integrate EMIS into day-to-day operations of HVAC systems demanded a culture shift. Monitoring and tracking goes beyond chasing down leaking pipes; it is a continuous improvement process akin to the Kaizen approach. Rationalizing decisions, documenting outcomes, sharing information, acknowledging mistakes, and collaborating to solve problems are some of the areas in which the team has had success.