By: Caleb Kline, P.E.
Organizations large and small have been making decarbonization commitments to reduce their greenhouse gas (GHG) emissions. For many organizations, the buildings that they own or rent make up a large portion of their GHG emissions. Reducing and eliminating these emissions can be done by replacing equipment that runs on fossil fuels with equipment that runs on electricity. As the electricity used is sourced from more renewable sources, the GHG emissions are reduced. With the addition of on-site solar generation or the purchase of 100% renewable energy, the scope 1 and 2 GHG emissions can be brought to zero. This process is called electrification.
While the process seems simple enough, getting it done within a limited budget is challenging. Few organizations can afford to completely renovate their buildings and replace all the fossil fueled equipment at once. Many older buildings will run into challenges finding electric heating equipment to match their existing equipment capacity. A decarbonization plan can address these challenges by improving building energy efficiency, rightsizing the heating equipment, and phasing the equipment replacement over time.
Resource Efficient Electrification
Gas fired heating systems in older buildings are commonly oversized. Replacing these systems with the same size electric heat pumps is prohibitively expensive and would result in poor performance. The New York State Energy Research and Development Authority (NYSERDA) suggests a process they call Resource Efficient Electrification. The process, represented by Figure 1 below, begins with reviewing the existing fossil fuel heating equipment size. After the review, energy efficiency measures are implemented to reduce the energy consumption and the required overall size of the equipment. After that, most of the load is replaced with a right-sized heat pump while some fossil fuel equipment remains. Overtime this remaining equipment is phased out through efficiency improvements or replaced with electric equipment.
Figure 1: Phasing Approach to Resource Efficient Electrification, from NYSERDA’s Empire Challenge
Inclination Engineering’s Decarbonization Process happens in main phases.
Phase 1 – System Review and Efficiency and Operational Improvements
This phase is similar to retro-commissioning and functions as a building tune-up and evaluation. The existing systems are investigated with special attention paid to the controls and operations. Malfunctioning equipment control components are identified and resolved. Diagnostic monitoring is used to identify improvements and measure the actual required capacity. A report provides the findings and suggested energy efficiency measures.
This phase concludes with operation improvements to ensure the persistence of energy efficiency gains. This involves staff training and the production of system’s manuals and other operation documentation.
Phase 2 – Decarbonization Planning
This phase evaluates the costs and benefits of several electric system replacement options, identifies a GHG emissions baseline, and creates the roadmap for the equipment transition. Taking the building heat requirement measured in Phase 1 determines the replacement system size. A schematic level design and a rough estimate of probable cost is produced for each system replacement option. A report with this information is presented to the client to get their feedback on the preferred system.
Once a preferred system is chosen, a transition plan is created outlining the steps involved to transition from the existing system to the preferred electric system. The plan starts with a GHG emissions baseline based on a review of historic utility data. The transition plan contains projects that can be initiated over an extended timeline, coordinated with equipment failures, budgets, and other building renovations. An estimated GHG emission reduction from the baseline is shown for each project.
Phase 3 – Equipment Transition
This phase is broken up into several projects that can be undertaken when the timing is right for the building owner. The projects are identified in Phase 2 and include equipment replacement as well as possible envelope improvements. The transition plan includes a schematic level description of each project that will need to be expanded upon by the design and construction team. At regular intervals and after each project, the GHG emissions level are checked and compared against the transition plan.
A decarbonization plan should be tailored to suite each building and the needs of the organization. Contact Inclination Engineering to discuss how you can start a decarbonization plan for your building.