Cooling Season Is Here. So Are Your Highest Electricity Costs

How rising electricity rates and cooling inefficiencies are driving operating costs across Ontario buildings

As Ontario enters the cooling season, building owners are approaching the most energy-intensive period of the year.

For most multi-residential buildings, office towers, and retail centres, summer electricity consumption is driven by one primary system.

Cooling.

Chillers, cooling towers, pumps, and ventilation systems work continuously to maintain indoor conditions. In many buildings, these systems represent the single largest electrical load during peak months.

At the same time, electricity pricing in Ontario is becoming increasingly sensitive to when energy is consumed.

Time-of-use structures and peak demand charges are placing greater financial weight on daytime and high-demand periods, precisely when cooling systems are operating at their highest capacity.

The result is a convergence of two factors:

Higher consumption and higher cost per unit of energy.

The cost of cooling at the wrong time

Cooling demand typically peaks during the hottest hours of the day, which often align with the most expensive electricity periods.

Without optimized control, many buildings operate their cooling plants at full intensity during these windows.

Chillers run harder than necessary. Cooling towers operate at fixed setpoints. Pumps circulate at constant speed. Ventilation systems bring in excess outdoor air that must be cooled.

These conditions drive up both total consumption and peak demand, increasing overall operating expenses.

For portfolio owners, the impact is material.

Even small inefficiencies during peak hours can disproportionately affect monthly electricity costs.

Common operational challenges

Across asset classes, similar patterns emerge in cooling system operation.

Lack of sequencing

Multiple chillers may operate simultaneously at partial load rather than staging efficiently. This reduces system efficiency and increases energy consumption.

Fixed temperature setpoints

Chilled water and condenser water temperatures are often set conservatively and not adjusted based on outdoor conditions, resulting in unnecessary energy use.

Excess ventilation

Ventilation systems frequently bring in more outdoor air than required. In summer, this air must be cooled and dehumidified, increasing system load.

Simultaneous inefficiencies

In some buildings, cooling and reheat systems operate at the same time, particularly during shoulder seasons or poorly tuned control sequences.

No demand awareness

Cooling systems are rarely managed in response to electricity pricing or peak demand conditions.

“In many buildings, cooling systems are operating based on fixed assumptions rather than real-time conditions,” said Josh Lewis, Chief Technical Engineer, NERVA Energy. “That creates unnecessary cost, especially during peak periods.”

The opportunity for optimization

Unlike capital upgrades, many cooling inefficiencies can be addressed through operational improvements.

Strategic adjustments to sequencing, setpoints, and system control can materially reduce energy consumption without compromising comfort.

Key opportunities include:

• Optimized chiller sequencing based on load

• Chilled water temperature reset based on outdoor conditions

• Cooling tower optimization to reduce condenser load

• Variable speed pump control to match demand• Ventilation reduction during peak cooling periods

• Pre-cooling strategies to shift load outside peak hours

  
  

These measures reduce both energy consumption and peak demand exposure.

The financial impact

The financial benefits of cooling optimization are twofold.

First, reduced energy consumption lowers overall electricity costs.

Second, improved load management reduces peak demand, which can significantly influence utility charges in Ontario’s pricing structure.

For large buildings, even a 5 to 10 percent improvement in cooling efficiency can translate into meaningful cost savings across a single season.

“Cooling optimization is one of the most immediate opportunities to reduce electricity costs,” said Trevor Shaw, Chief Operations Engineer, NERVA Energy. “It directly impacts both consumption and peak demand.”

A seasonal strategy, not a reactive adjustment

Cooling season is often treated as a fixed operating condition.

In reality, it is one of the most controllable aspects of building performance.

Outdoor temperatures fluctuate daily. Occupancy patterns vary. Electricity pricing changes throughout the day.

Buildings that adapt to these variables operate more efficiently.

Buildings that do not absorb unnecessary cost.

The path forward

As electricity rates continue to evolve and peak pricing becomes more pronounced, cooling system performance will play an increasingly important role in operating budgets.

For owners managing diverse portfolios, the ability to optimize cooling across multiple asset classes is a strategic advantage.

The buildings that perform best this summer will not simply be those with the newest equipment.

They will be the ones that operate most intelligently.

About NERVA Energy

NERVA Energy is a distinguished multidisciplinary engineering firm, renowned for its cutting-edge energy performance solutions. With an elite team composed of seasoned energy engineers, M&E engineers, and seasoned in-house mechanical technicians, NERVA is steadfast in its commitment to delivering turn-key solutions. These solutions not only amplify building energy efficiency but are also backed by a steadfast financial performance guarantee.

To learn more about the company and our services, visit:

 www.nervaenergy.com