This session will discuss the advantages and challenges of using CO2 Heat Pumps for decarbonizing and efficiently electrifying commercial Domestic Hot Water systems. The session will outline and discuss the Mitsubishi Electric Heat2O DHW solution along with other CO2 DHW systems and their applications. The functionality, operation, scalability, and relevant design challenges related to these types of solutions will be explained. This session will discuss the use and benefit of CO2 as a refrigerant and its impact on environmentally sustainable buildings.

To achieve mass adoption of offsite construction, the building process as we know it has to be reevaluated from multiple perspectives. This is especially true when combined with the goals of scaling up low-carbon and high-performance objectives. The session will explore how the three primarily residential companies have built their businesses around offsite manufacturing principles and have developed strategies to “unsilo” the industry.

With the coming updates to building energy codes, there is an anticipation of growth in the volume of Passive House buildings. It is important to have a fully scalable approach to successfully guide teams from scope development through certification. This session will give a “behind the scenes” look into the process and demonstrate how to best handle the expansion of Passive House projects with a look at the perspective of the project manager, the energy modeler and the PHIUS verifier.

Methods for electrification of DHW in multifamily buildings all pose challenges. This session will provide an overview of existing technologies and a brief history of how we arrived at central air-source heat pump technology as the least problematic solution today. We will use recent design-phase case studies to illustrate cost, estimated energy use, mechanical space requirements, system and equipment peculiarities, metering strategies, maintenance requirements, what we’d like to learn from systems as they’re installed, and why the alternatives for electrification of DHW are even worse!

Passive House buildings go hand-in-hand with on-site generation and electrification, but what happens when you have code-required emergency power backup? The Kenzi tackled the wicked problem of designing, pricing, and permitting the first all-electric building above four floors in the City of Boston. We will dive into the nitty gritty of design, funding, and procurement, reveal our strategy for Boston Fire Department concerns, and discuss what code language we leaned on to pull it all together.

Dense packing cellulose in roof slopes has been a common insulation retrofit strategy in New England for a long time, however technically it has not been allowed by code without the inclusion of venting or foam insulation at the roof sheathing for condensation control. Previous BuildingEnergy presentations have suggested that further research should be done to evaluate whether vented attic space above unvented dense-packed slopes could manage moisture more effectively than insulating all the way up to the ridge.

Think you know effective heat pump sizing and design? Significant market growth of cold-climate air-source heat pumps has resulted in new insights and lessons learned. Come explore new tools and best practices to enable improved design, sizing, and selection of ASHPs in this session with NEEP and Abode, and stay on the leading edge!

With rising determination to fight the climate crisis worldwide, practitioners are finding the Passive House standard a potent solution for the building sector. As passive and other sustainable building standards are proliferating worldwide, those standards meet a host of different location-specific challenges. This diverse panel of women architects and certified Passive House consultants are seeking to understand the adaptation of the Passive House standard globally.

Typical university dormitory projects are capital intensive and take several years to complete. This project turned this practice on its head. Using modular construction, on-site precast foundations, an integrated design-build team and low-embodied-carbon materials in a holistic approach, Colby College housed students as quickly as possible while ensuring the highest standards of beauty, accessibility, energy consumption, and healthy materials. Design started in September 2021, and students moved in in August 2022.

Research has shown that solar adoption in a neighborhood spurs more solar adoption. Conversely, if clean energy adoption is not seeded in other communities, these communities lose out on the benefits of clean energy. This panel will provide lessons learned and best practices for using the community coach/ambassador/advisor model to promote clean energy in underserved communities. Speakers will talk about addressing language barriers and building trust.