Greenlea Meats sought Hennessy’s project and electrical expertise to provide electrical services for a new Cooltec Freezing Carton Tunnel at their Morrinsville plant. With full sorting capabilities the carton tunnel possesses advanced blast-freezing technology. It was built on-site by the Cooltec team, along with Greenlea’s new Frick ammonia compressor.
Hennessy took charge of delivering all wiring of the tunnel automation. Our team worked flexibly to navigate lengthy material delays, competing contractor timeframes, and an extended build timeframe.
The tunnel required additional ammonia controls to be installed and wiring of a new 335 kw Frick ammonia compressor and a new variable speed driver (VSD) to ensure smooth and efficient operation. Two new 400-amp submains were also needed, along with general electrical power and lighting in the Cooltec Tunnel.


To meet the October 2022 deadline, our team developed a project timeline that accommodated the Cooltec Tunnel builders and other contractors’ timeframes. Relationships were key, and by working together with the project partners, we enabled all teams to achieve their milestones without interrupting each other, while adapting to delays throughout the build timeframe.
Our experienced team designed a customised ammonia control system based on the function description provided by the refrigeration engineer. Our design integrated the site’s electrical limitations, variable controls and future power requirements to ensure the Cooltec blast freezer and Frick Ammonia compressor would enable Greenlea to meet their production and operational goals.
We also designed and installed general lighting, emergency lighting and power for the Cooltec blast freezer and tunnel to support the project’s deliverables.


Our skilled and experienced team successfully delivered all project requirements, including:
Our team loves taking on a challenge, and this project certainly provided us with that – with delivery interruptions, multiple contractors, and a moving timeframe.
Our team worked flexibly and built great relationships to ensure the project was a success. We delivered a comprehensive electrical solution that has helped prepare Greenlea for a successful future.
