The Reduce – Improve – Switch model for Durham Region

The Durham Community Energy Plan (D.C.E.P.) depicts a Reduce-Improve-Switch model (Figure 9.) as a methodology for low carbon fuel switching. The transition to zero carbon renewable sources of energy requires an evaluation of the entire system, and is not isolated to each granular retrofit within a facility.

It is best practice to evaluate envelope and load reduction strategies prior to mechanical retrofits, as these upgrades contribute to avoided capacity and allow for right-sizing of mechanical systems when lifecycle replacements come due. This provides more fiscally responsible investments and a critical reduction in demand, constituting “strategic fuel switching”. Strategic fuel switching describes fuel-switching that saves the consumer money, reduces the total system wide energy consumption and lowers total greenhouse gas emissions in comparison to the previously replaced technologies. 6 Waste heat recovery solutions also have a large impact in reducing demand to mechanical systems and whole facility boundary.

The Reduce-Improve-Switch approach also optimizes future capital expenditures on renewable and distributed energy systems by right sizing local energy generation to lower loads, and leaving potential for expansion where possible (i.e. Photo-voltaic arrays can be limited by availability of open horizontal space).

Reducing demand and limiting conversion losses through local production is essential for Ontario’s low carbon growth. Considering the limitations of the changing energy system provides insight on how a proactive energy position can help future proof the City’s assets while also contributing to energy security for our community.

The overarching requirement for whole system planning demonstrated in the Reduce-Improve-Switch model has been used to inform our Net Zero Retrofit Strategy, implementing a long term plan for the City’s carbon reduction goals.

Goal Develop a meaningful plan to target greenhouse gas reduction while increasing the resiliency of high priority assets that will serve the City of Oshawa for years to come.

Action Upon adoption of this plan, the Corporation of the City of Oshawa will advance a detailed Net Zero retrofit engineering study. The engineering study will model, and quantify a path to achieve 80% reduction in corporate greenhouse gas emissions by targeting top gas consuming facilities (shown in Fig.10) for fuel switching, and providing detailed design specifications for project delivery.

The evolving low carbon future provides a unique opportunity to mitigate commodity market vulnerability through future planning that can best be implemented the sooner we begin. These detailed studies will constitute the first step in achieving the new corporate target of 100% Net Zero emissions by 2050.

Table 5 outlines the G.H.G. emissions that correspond with the top 8 natural gas consuming facilities in the City of Oshawa’s building portfolio. By targeting a select number of these facilities in the Net Zero Retrofit Strategy, we can reduce the entire emissions baseline substantially. The table shows the top five gas consuming facilities’ G.H.G. footprint being equivalent of 80% of the 2007 baseline emissions.

The proposed engineering study will involve the following stages:

1.Define the top consumers that best suit fuel switching and achieving 80% Net Zero emission reductions.

2.Complete Net Zero Retrofit designs, with options provided.

3. Create a roadmap for delivery, defining technologies that need to be converted in tandem, and aligning with the capital plan by establishing timelines for action that is the best fit with projected asset renewal.

• Waste heat recovery systems

• Lighting upgrades

• Envelope improvements

• Defined operational set points to maintain predictable loading Methods of Load Reduction

Fuel Switching

Electrifiication

• Specification of systems

• Schedule of staging for linked systems, capital budget alignment etc.

• General pricing

• Carbon offset requirements

• Redundancy requirements or backup compatibility

Limitations of Fuel Switching

Energy Generation and Renewables

• On-site renewable generation technology options

• Required size of proposed systems

• Feasibility for implementation and location

• An approach that considers the most economically efficient pathway

• Critical Asset Infrastructure would be prioritized for community resiliency

• Technological feasibility

• Emerging technologies that may further impact carbon reduction between now and 2050