Unlocking grid flexibility: Strategic deployment of modular batteries in Canadian grid substations

As the energy sector undergoes a profound transformation, local utilities are facing growing pressure. Aging infrastructure, the electrification of heating and transport, and the proliferation of distributed energy resources (DERs) are driving an unprecedented need for grid flexibility. These challenges are especially visible in Canada, where thousands of distribution substations connect communities to the grid. Most of these substations serve less than 10 MW of load and they hold immense untapped potential.

TROES believes modular BESS technology is particularly well-suited for deployment at these substations. Modular systems provide cost-effective, scalable energy storage solutions that can be tailored to local needs. They can be installed quickly, with minimal civil work; integrated into existing transformer and switchgear layouts; and managed through remote energy management systems. In our experience, these deployments offer a flexible, future-ready foundation for grid modernization.

We recommend two key deployment strategies: “Feeder head” and “feeder tail” integration. Both approaches support multiple objectives and address different grid challenges.

Grid reliability at source

Feeder head deployment places the BESS immediately downstream of the substation’s main transformer. In this configuration, the system charges during off-peak hours and discharges during periods of high demand, relieving transformer stress and enhancing feeder reliability.

Through this setup, we’ve seen measurable benefits:

• Peak shaving that defers costly transformer upgrades
• Millisecond-level response times that manage industrial load fluctuations
• Grid services participation through programs like IESO’s [the Independent Electricity System Operator] demand-response and capacity markets
• Black-start and islanding capabilities that enhance community resilience – particularly valuable for First Nations and rural areas
• Voltage and frequency regulation in long feeders with high DER penetration

This model is especially effective in situations where load volatility threatens equipment lifespan or where utilities are considering non-wire alternatives to major capital investment.

Grid growth without infrastructure

By contrast, feeder tail deployment positions the BESS further downstream, typically midline or near key load centers. In this setup, the system operates much like a virtual generator, directly serving local demand and improving voltage stability at the grid’s edge.

For fast-growing communities or industrial parks located at the end of feeder branches, this model provides several advantages:

• Grid capacity expansion without substation upgrades
• Reduced line losses and voltage drops
• Increased hosting capacity for rooftop solar or electric vehicle (EV) chargers
• Better regional load balancing under local utility control

We have found that this configuration enables third-party aggregators and municipalities to implement energy storage even in areas where upstream capacity is constrained.

Why now?

What makes this moment ideal for distribution-level BESS deployment is the alignment of technological readiness with enabling policy. Government programs and utility incentives are finally recognizing and supporting the value of modular energy storage.

Several key developments are driving this momentum:

• NRCan’s [Natural Resources Canada] Smart Grid and Clean Energy programs offer grants and cost-sharing for eligible projects
• IESO market reforms are accommodating non-wire alternatives like BESS
• Municipal net-zero targets in cities such as Toronto and Ottawa depend on flexible local grid solutions
• EV expansion across provinces is already straining distribution capacity, making local flexibility essential

This policy environment signals that utilities and local partners do not need to act alone. Capital support is available and with the right partnerships in place, projects can move efficiently from pilot stage to long-term deployment.

Substations: the ‘missing middle’

In Canada’s energy transition, it is essential not to overlook the electricity distribution layer. Distribution substations are the unsung workhorses of the power system and they represent one of the most cost-effective and impactful locations for deploying modular energy storage. TROES believes integrating BESS into this layer of the grid is key to unlocking flexibility, accelerating electrification, and supporting a more resilient, decentralized, and decarbonized energy future. The opportunity is real, the technology is ready, and the time to act is now.

About the author:

Vienna Zhou, CEO & Founder of TROES

Vienna is a seasoned leader with over 20 years of experience in renewable energy and cleantech, including roles in Fortune 500 companies and government. She holds degrees in mechanical engineering and business (MBA) from top-ranked universities and founded TROES in 2018 to pioneer advanced Battery Energy Storage Systems and microgrid solutions. Under her leadership, TROES has achieved international success, winning the 2023 OCI Mind to Market Award and earning recognition from IBM VentureLAB and the City of Markham.