Longos Walkers Line

At a Glance
• System Configuration: 2 × C65 Dual Mode Capstone Energy+ Microturbines, 80-ton absorption chiller and custom PLC-based microgrid controller
• First-of-Its-Kind Integration: North America’s first microgrid pairing CCHP microturbines directly with low-GWP CO₂ refrigeration racks
• Financial & Energy Impact: ~$130,000 CAD / year in savings; generates >1,100 MWh/year of on-site electricity while displacing ~250,000 kWh via thermal cooling
• Environmental Impact: Reduces greenhouse gas emissions by 1,250 tonnes/year by displacing grid peaking plants and eliminating high-GWP HFC refrigerants
• Operating Mode: Dual Mode with sub-second, automated grid-to-island transition for full outage protection


The Challenge
Grocery retail operations are extraordinarily energy-intensive and highly vulnerable to grid disruptions, where a single power outage risks massive inventory loss through food spoilage. Upgrading its Burlington location, Longo’s sought to transition away from traditional high-GWP HFC refrigerants toward an eco-friendly CO₂-based refrigeration system (GWP = 1). However, CO₂ refrigeration systems demand absolute power continuity to prevent catastrophic pressure build-up and gas venting during power loss. Furthermore, CO₂ systems lose efficiency in warm summer temperatures when forced into trans-critical mode, requiring a reliable thermal precooling solution to maintain optimal performance.


The Solution
In partnership with Neelands Group and Veristar Energy, Longo’s installed a 130 kW CCHP microgrid engineered for year-round seasonal adaptation and seamless backup power.
• Tri-Generation Microgrid Power: Features two Capstone C65 microturbines supplying 130 kW of continuous baseload electricity while supplying high-grade exhaust heat to thermal recovery modules.
• CO₂ System Precooling via Absorption Chiller: Channels exhaust heat into an 80-ton World Energy absorption chiller to deliver chilled water, keeping CO₂ refrigeration racks in high-efficiency sub-critical mode during hot summer months.
• Dynamic Seasonal Heat Recovery: Reclaims 860,000 BTU/hr of thermal energy—redirecting hot water to make-up air units for summer dehumidification and facility space heating in winter to offset gas consumption.
• Dual-Mode Outage Safeguard: Automatically isolates from the utility grid during outages, maintaining uninterruptible power to refrigeration compressors to prevent CO₂ venting and food spoilage.


The Results
• $130,000 CAD Annual Operating Savings: Drastically lowers utility spend across power, space heating, and refrigeration compressor loads.
• 1,250 Tonnes Annual GHG Reduction: Cuts corporate carbon footprint by eliminating high-peaker grid power reliance and transitioning away from high-GWP chemical refrigerants.
• Absolute Inventory & Refrigeration Protection: Eliminates store outage risks and costly gas venting through rapid, dual-mode microgrid islanding.
• Award-Winning Sustainability Leadership: Establishes a scalable blueprint for low-emission food retail operations across North America.