Summer energy conservation reduces demand on the grid and leads to big savings

With last week’s taste of sweltering weather, Facilities Management (FM) is revving up its award-winning energy reduction strategy. According director of Sustainability, Heather Hyde, this year’s process will continue to reduce the university’s utility fees, while maintaining indoor air circulation.

“After a decade of mitigating power during peak summer days, we’ve adopted some of the most innovative and efficient systems,” said Hyde. “It’s our secret sauce – and we continue to perfect it.”

Western’s demand management energy conservation program is one way our campus conserves energy during the highest intensity peak times on hot summer days. The demand management program has been running for ten years at Western, and the program continues to improve by conserving energy with minimal disruption to the campus community. Annual process improvements have brought us to the point that we are able to strategically conserve energy while building occupants experience minimal difference in indoor air temperature.

Air flow and ventilation remain a priority as part of Western’s COVID-19 mitigation tactics, and the demand management program has no impact on the ventilation of campus buildings. Essentially, demand management means a temporary increase in chilled water temperature with a purpose of reducing our energy needs during peak times.

Hyde noted that air temperature may increase slightly during demand management, but fans continue to run, keeping occupants comfortable and buildings sufficiently ventilated.

For the past ten years, FM has worked closely with the campus community to mitigate hefty energy fees. The effort has led to savings of roughly $2-2.5 million annually. However, over those years, the rules of the game have changed and the strategy to avoid these fees has had to change with it.

In 2012, Western was one of the only universities taking action to reduce energy during the province’s peak energy days. The strategy included broad reductions to systems on campus. The efforts were initially referred to as Global Adjustment (GA) because they were in direct response to the added GA fees that appear on the University’s hydro bill. They have since been identified as part of the overall Demand Management strategy that includes all of Western’s energy conservation efforts.

In subsequent years, more organizations followed Western’s lead and began shedding electrical load on select days. As a result, energy peaks became more unpredictable as electricity draw was being impacted by Ontario businesses consciously changing energy habits.

To stay ahead of competitors, Western invested in new chilled water valves, allowing for isolated reductions to specific buildings and rooms on campus. The new, remotely controlled valves can be operated independently and in increments as opposed to either just open or shut. As a result, most occupants shouldn’t notice much change in indoor air temperatures during mitigation events.

“We’ve focused a lot of our attention on improving the operation of our chilled water system,” said Hyde. “This is where we feel we have made the greatest gains.”

FM later built on those efforts and installed new technology that further automates chiller controls. With the switch there are evident cost savings, but more importantly, the Division can provide more comfort to customers throughout the warmer months and on peak energy day. With the push of a button, the chiller plant sequences will revert to ‘Demand Management’ mode. This will adjust chiller plant setpoints and signal to WES building automation system to increase chilled water return temperatures. The increased chilled water return temperatures combined with reduced chilled water flow impact both required pumping power and chiller compressor electrical consumption.

This year’s efforts will fine tune the automated sequencing and build upon the energy loop between the north and south chiller plants. During the anticipated peak hours, the Power Plant will be able to optimize chilled water production and savings from its chillers by selecting the most efficient equipment across the two main campus chiller plants.

Thomas Stein, Power Plant Manager, discusses the evolvement of the program over the last decade. “The first implementation of demand management on campus 10 years ago was stressful for operators and equipment. Shutting down chillers at peak demand would push operating chillers and auxiliary equipment to their limit resulting in equipment reliability issues and inefficient operation, air handling units on campus would compete for the reduced chilled water supply causing cooling inconsistencies. The evolution of demand management strategies and programming over the years has made energy reductions repeatable and less impactful to the users. During demand management today the chillers and pumps all seamlessly dial back to operate in their most efficient curves providing more chilled water than previously possible with less electricity.”

Hyde points the importance of support from campus community. The Demand Management team in FM works closely with staff and faculty to limit running high-intensity equipment such as the Wind Tunnel when possible. Building occupants also contribute to the energy reduction by unplugging unused electronics and pulling down nearby blinds.

“Our efforts to invest in our equipment is one thing, but having the support and commitment from our colleagues on campus is extremely valuable,” said Hyde.

This year Western placed first in Canada and third in the world in the Times Higher Education Impact Rankings for our work towards the United Nations Sustainable Development Goals. This achievement is made possible by sustainability initiatives from all across campus, like our demand management program.