Sunnybrook Health Sciences Centre

High Voltage Emergency Power Renewal

HH Angus has been providing mechanical and electrical engineering at the Sunnybrook campus since 1945. The complex now totals more than 2,000,000 ft2. In that time, a great many individual projects have been successfully delivered. The high voltage emergency power renewal described below was a large infrastructure improvement project. Other large project examples from our work at Sunnybrook include M Wing and the Toronto Sunnybrook Cancer Centre.

High Voltage Emergency Power Renewal

The renewal project involved replacement and upgrades of existing forty-year-old standby generators and associated infrastructure. The specifics included: installation of 8.75MW of diesel generators, new medium voltage switchgear, a selective catalytic reduction system for each new generator (for emissions control), fuel oil system upgrades and replacement of a campus-wide PLC-based load management system. The selective catalytic reduction systems allow Sunnybrook to use their plant for offsetting peak loads during summer months and to realize savings in annual hydro expenditures.

The high voltage emergency power renewal project replaced the existing 4160V generating capacity of 4.3MW with 8MW of new 4160V generating capacity. A 600V, 750kW generator replaced an existing 400kW generator.


Mechanical Engineering | Electrical Engineering | Prime Consultant 


Status: Completed 2015


Toronto, Ontario


Large infrastructure improvement project involving architectural and structural design for a building plenum expansion | Installed  8.75MW diesel generator | Added selective catalytic reduction system for each new generator | Multi-phase project to ensure service redundancy for critical functions

Prime consulting services

HH Angus was the Prime Consultant, as well as the electrical and mechanical engineer for the project. We retained the services of an architect and structural engineer to design a building plenum expansion for the new diesel generators. The general trades work included extensive structural steel work, excavation and concrete work.

HH Angus managed equipment procurement for the project and helped Sunnybrook Health Sciences select an equipment supplier to provide a .9 million CDN (2013) equipment package.

Phasing for service redundancy

The project was multi-phased to allow temporary power to maintain service redundancy for critical healthcare functions while existing diesel generators were decommissioned and the new structure constructed and plant equipment installed.