Seniors’ homes (MDA): Energy mix, the preferred solution to meet sustainable development requirements

Announced as “a major transformation in housing environments for seniors,” the seniors’ homes project, launched by the Québec government in 2019, has the goal of creating human dimension living environments for seniors with little to moderate autonomy. Divided into modern, friendly “living units,” each accommodating 12 residents, the buildings include between 12 to 192 air-conditioning rooms.

In this ambitious project, the MDAs have to integrate best sustainable development practices, while respecting certain economic imperatives. What are the challenges that the master team (Bouthillette Parizeau) had to meet in this regard? What solutions did it propose and why? That is what we plan to find out in this case study.

• Context
• Mandate
• Solutions
• Results
• Role of Énergir in this project
• Conclusion

Overview of projects

Solutions

Master team choices

^*Heating: Explanation of choices

Select the best energy available at the best cost

In the first drafts, an all-electric strategy was envisaged, but given the requirement for boiler redundancy in case of power outages, huge capacity generators would have been required.

Using gas-fired boilers/water heaters allows an appreciable reduction in the capacity of the generators and an average investment saving of about $4 M compared with the use of 100% electric boilers.

Besides considerably reducing capital costs, natural gas boilers also allow savings in the operating costs of managing electricity peaks.

Optimize peak management

When natural gas is available, gas-fired boilers/water heaters are used to manage electricity peaks, respecting criteria 2 & 3 of CCAP 2020.

Peak management allows a quite significant energy saving of about $5/m2, which translates into an average annual saving of $26,000 for a 48-bed MDA, $40,000 for a 72-bed MDA, and $52,000 for a 96-bed MDA. The saving comes from reducing the monthly peak and removing the applicability of the penalty imposed by Rate M.

Note: This peak management strategy is not used for buildings that use propane because of the high costs of propane compared with natural gas.

Technologies envisaged but not retained

Solutions from the concept teams

According to the concept teams, certain variabilities can be observed on the various projects, the most important being:

• 100% outdoor air systems with heat recovery
• Recovery chillers
• Heat recovery on outdoor air with lower efficiencies
• Single duct systems with electric terminal reheat to ensure comfort

Presentation of results compared with requirements

Table 4 - Sources of energy savings

Table 5 - Goals related to CCAP 2020 (to be removed from table)

Role of Énergir in this project

Énergir participated in the MDA project by supporting the master team in seeking solutions that optimally meet requirements while maximizing the amount of financial assistance available. This collaboration led, in particular, to grants averaging $70,000 for 96-bed MDAs under the New efficient construction program.

Nathalie Boulet, Eng., CEM CEA Leed C+CB
Project Manager,
Bouthillette Parizeau

Sami Maksoud, Eng., M. Eng., MBA, CMVP®
Advisor, Energy Efficiency, DATECH
Énergir