Case Study: Powering Western University’s path to net-zero

Responsible for the majority of Western University’s greenhouse gas emissions, Western’s 102-year-old power plant is the focus of a $16-million upgrade that is expected to reduce the London, Ont. university’s overall emissions by up to 30 per cent.

This significant equipment installation is at the heart of Western’s near-term sustainability goal of 45 per cent carbon reduction by 2030, and long-term ambition to achieve net-zero emissions by 2050.

“This project is going to replace one of our oldest boilers with an electric boiler… which will really get us to our 2030 goal,” says Heather Hyde, Western’s sustainability director. “Our steam system… accounts for about 75 per cent of our overall emissions, so a significant portion. And that’s why we’ve prioritized this project, because it has a very significant impact.”

The $16-million project allocation includes $4.75 million in federal funding from the government’s Decarbonization Incentive Program, which funds clean technology projects from carbon tax proceeds.

Two new 6.9-megawatt electric boilers will replace one of five natural gas boilers at the power plant and will ultimately generate 40 per cent of Western’s steam requirements. It’s a multi-year undertaking expected to be completed by March 2026.

Western’s power plant, built in 1922, produces the steam that supplies the energy for heating and cooling systems in buildings across campus, including London Health Sciences Centre’s University Hospital. Dubbed a “city within a city,” Western’s campus hosts nearly 100 buildings spread across 250 hectares of land in the heart of the city of London in Southwestern Ontario.

Integrating new electric boilers into an established steam network presents a host of technical challenges that require careful planning and strategic foresight. From determining connection points to managing electrical demands and ensuring system reliability, every aspect of the project requires precise coordination and thorough engineering expertise.

“We’re studying how to do this [installation] with minimal interruption to the steam supply to the customers,” explains Stephen Burton, power plant manager and chief engineer at Western’s Facilities Management department.

A big part of the project’s planning process is ensuring the power supply for customers continues with little to no interruption as the new electric boilers are connected to the steam network. This is especially critical for the hospital building.

“There’s a number of connection points to the existing steam system that have to be analyzed and engineered and determined where to connect,” Burton says. “There is a steam loop that’s affected by this (for which) we’ll have to manage alternative routing. So, we’ll have to arrange the shutdown of that system and how that’s going to connect, with minimal disruption to customers on that loop.”

Boiler basics
Electric boiler technologies and brands vary. One of the first tasks Burton and his team faced was to evaluate and select the right type of electric boiler that fits Western’s requirements and infrastructure.

“When we looked at three different technologies [for the boiler system] we had to ask ourselves – as our first entry into electric boilers – we want to have something that has a lot of moving parts. Does it require extra special water chemistry? Is it maintenance-friendly? Can it be supported by the OEM? What’s the experience in the field with the different equipment?” says Burton.

The university considered three types of boilers, including immersed type electrode boilers and the jet type electrode boiler. In the end, resistance element electric boilers from Chromalox Inc. came out as the most ideal solution for the power plant.

“The resistance element boiler is a simpler design… it also fits our [plant] layout,” Burton explains. The first two considerations are taller, more complex and require more vertical space, which the plant’s existing space cannot accommodate. The resistance element boilers have a lower profile but longer length, and have less moving components, he adds.

Having a larger footprint does mean expanding the power plant’s floor space to accommodate the new boilers. The main floor will be expanded to 357 square meters through a building extension to the existing plant.

The electric boilers’ turndown ratio was also a huge consideration for the power plant engineering team. With a turndown ratio of 100:1, Western’s new electric boilers will provide much better efficiency in responding to the highs and lows of energy demand.
“If the steam demand goes very low, these [new boilers] can respond to that,” Burton says.

The high turndown ratio will work well with Western’s energy demand management program, which forecasts, plans and manages electrical consumption across campus. During high provincial electrical peaks, Western needs to reduce electrical consumption as part of the overall energy management. Electric boilers that can maintain efficiency at low loads is a key consideration.

“If we’re running these [boilers] in the summer, we’re going to have to bring them down. So, when they come down to a lower load, to reduce our peak electrical demand, a high efficiency on the turndown ratio is very important,” Burton says.

Scoping studies
With the new electric boilers on order – delivery takes about 50 weeks – Burton, along with the Western projects team and engineering consultants from WSP are analyzing all aspects of the connection points and interfaces for the new boiler systems. They are also in discussions with London Hydro, the local utility provider.

“We also have a number of auxiliaries,” adds Burton. “For example, you have a boiler like this but you have pumps and different controls that are on this boiler. We have to feed those and maintain a level of redundancy with our own plant equipment.”

The engineering studies being undertaken also involve an assessment of the substations that will feed the two new 6.9-megawatt boiler units. This is important to ensure system reliability, which Burton says is one of the bigger technical challenges Western and the WSP consultants are sorting out.

Systems connections and considerations are not the only work being done in preparation for the new boilers: building the in-house knowledge base to operate the new boilers is equally important. Burton notes these state-of-the-art boilers present a learning opportunity for the engineers and personnel at the power plant.

This is not the first time a new technology is being introduced at the plant. Throughout the course of its 100-year history, Western’s power generation hub has undergone a series of upgrades and iterations. Starting out with two small, coal-fed steam boilers in 1922 – then considered ‘innovative’ by 1920s standards – it has come significantly far. In addition to the five large boilers it houses today, the power plant also has four chillers, three air compressors, and kilometers-long pipes and tubes that connect the power generator to the campus’s steam network.

The plant has a total of 15 power engineers and personnel, including Burton. Training will be one of the key aspects of the project.
“This is relatively new technology for our power engineers. We have a staff of highly skilled power engineers here who are going to have to be trained and familiarized with this equipment, with this technology. We’re going to have to gain operating experience with it to see how well it responds and how well it connects to our system,” Burton says.

Sustainable solutions
Western’s sustainability goals are outlined in the university’s comprehensive strategic plan launched in 2021, committing to become net-zero by 2050.

The electric boilers, once operational, will significantly help Western get to its interim goal of reducing its emissions 45 per cent by 2030. Western Sustainability is the lead office spearheading the university’s “multifaceted” approach toward carbon reduction and, eventually, net-zero emission.

The power plant upgrade is part of a bigger campus-wide Green Building initiative that also includes a deep energy retrofit program, which is an ongoing undertaking to renovate older buildings to improve their energy efficiency and reduce carbon emissions.

Western is also increasing its roster of LEED-certified buildings. Leadership in Energy and Environmental Design (LEED) is a widely used international rating standard that provides a framework for buildings to lower carbon emissions, conserve resources and reduce operating costs through sustainable practices.

As Western expands its physical footprint, it also aims to shrink its carbon footprint. “We have ambitious growth plans. And so we continue to grow and build buildings. We also have a low-carbon building design that’s now being incorporated into all of our new buildings,” says Hyde.

One such building will be unveiled in the fall of 2024. The new Ronald D. Schmeichel Building for Entrepreneurship and Innovation is Western’s first-ever net-zero building on campus.

“[The new building] is really setting a standard for design moving forward,” Hyde says. The building also features: a geo exchange system for heating and cooling the entire building; triple-paned windows for energy efficiency; and solar photovoltaic panels on the roof to generate renewable energy.

Reality check
As the global push towards decarbonization gains momentum, transitioning from fossil-fuels to low-carbon energy generation requires much more than goal setting and funding allocations. On the ground level, the path to net-zero requires careful planning, strategic expertise and a collaborative approach.

Building new projects from the ground up – such as Western’s new net-zero building – may have a completely different decarbonization journey than retrofitting an old, existing infrastructure. It’s more challenging, but not impossible, Burton says.

“My (views) on decarbonization (is that) It’s all possible, but it has to be done at the right pace with a lot of expert input,” says Burton.
Retrofitting old facilities with new equipment and new technologies is fraught with challenges, both foreseen and unforeseen. Connecting new equipment with older operating systems will likely pose some connectivity issues and load challenges. Particularly as more organizations pursue their own net-zero goals and move toward electrification.

Burton says the key to success is solid planning. “Solid planning and understanding what you have in your own system, asking the right questions all the time, going over drawings multiple times, and the technology selection,” he says.

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