Berkeley Efficient & Resilient Mixed-Use Showcase (BERMUS)

Project Innovation

The Project Team’s goal with regard to Sustainability was to design an integrated system of proven technologies that achieves the following:
1. Zero Net Energy Plus Resilience (Annual production of solar microgrid system offset >100% of expected annual consumption);
2. No Net Grid energy Drawn during Peak Hours (4 PM to 9 PM);
3. Indefinite Resilience for Critical Loads;
4. Small Operational and Embodied Carbon Footprint;
5. Reduced Future O&M (“Operations and Maintenance”) costs; and
6. Significant, Sustained Benefits to Low-Income Homeowners (including lower resident utility bills and improved resident health outcomes).

Woolsey Gardens is innovative because it wholly integrates proven, commercially available technologies into one building. Because the building will be occupied by low-income households with access to fewer resources than those available to more affluent households, the Project Team wanted to mitigate the technology risk borne by the low-income households. The Project Team relied on the following three guiding principles to mitigate this risk:
• Utilize commercially available technology.
• Employ technology requiring no changes to the existing building code and public policy.
• If an early adopter, then selected technology should be (a) robust; (b) cost effective; and (c) consultant recommending technology has firsthand familiarity with the technology and has a verifiable track record utilizing the technology

Woolsey Gardens features five+ key technologies that enable the building to reach its zero-emission target, not only surpassing the performance of a Standard “Baseline” Building (one that just meets the 2022 California Building Code), but also providing a viable pathway for future projects to significantly reduce their level of operational and embodied carbon footprint. The five+ key innovative energy efficiency features include the following:
1. Zero Net Energy Solar Microgrid System. Please see the Final Report Section 2.3.3 for detailed information on the innovative ZNE Solar Microgrid System. What distinguishes this system is that Zero Net Energy is achieved for a dense, 8-story building on a small lot (no solar over parking; all solar is over the roof). The System is constructable, fits within the current policy/legal framework, and exceeds VOR123 resiliency requirements
2. “Enhanced Passive Design” Mechanical Equipment. This strategy addresses certain shortcomings with “Passive House” strategies, including noise transmission and susceptibility to unfavorable outdoor air quality events like wildfires. The system results in nearly a 40% reduction in space cooling/heating Energy Use Intensity (“EUI”) versus that for a standard, 2022 code compliant building. Key features include enhanced comfort cooling system coupled with an enhanced passive envelope design, increased ventilation which allows for “free cooling”, and background “comfort cooling” which enables comfort to be maintained when windows are closed. What distinguishes this system is that addresses wildfire smoke concerns and near-term increases in local average temperatures due to climate change because it is a robust, fully centralized system that can be adapted to future conditions (e.g.: carbon filtration/wildfire smoke, cooling equipment for rising temperatures).
3. “Air Source Heat Pump Domestic Hot Water (“ASHP DHW”) with Thermal Storage & Waste Heat Recovery. The system features larger hot water storage tanks that collectively store about 500 kWh of energy, reducing Project battery requirements and a 44% reduction flow fixture water use versus CalGreen and DHW heating energy savings via ultra low-flow fixtures. Notably, the system results in an over 40% reduction in EUI over that for a minimally code compliant building. Water heaters are inactive during peak hours and cold water is preheated via heat recover coils on the sanitary waste main reducing heating demand. CO2 ASHPs have a lower Global Warming Potential and higher heating efficiency. Technology utilizing phase change material has yet to achieve commercialization in the US; the Project Team decided that this pre-commercialization technology into a project housing low-income households was a risk that the Project Team did not want to take.
4. Comprehensive Demand Reduction. Please see Section 2.3.2b for detailed information about Woolsey Garden’s unique Comprehensive Demand Reduction Program. What distinguishes are as follows: (1) It leverages one of NCLT’s four core competencies, resident stewardship/engagement, to implement the program; (2) Resident Consumption Dashboards rely on existing, commercialized hardware with open-source backend Application Programming Interface (“API”), allowing for customization; (3) It features a “Financial + Other Dis/Incentives Program, a formal robust program that rewards moderated consumption and discourages excessive consumption; (4) The Program fits into current CPUC policy surrounding the definition of a “utility” and does not require change in public policy to implement; and (5) The Program utilizes scientific economic analysis to design, monitor, and update the program continuously.
5. Mass Timber. The Project is on target to be the first Type IV-C fully multifamily building constructed in California. Recently, the Project was named a winner of the prestigious 2023 Mass Timber Competition, a national competition sponsored by the USDA, Softwood Lumber Board, and Woodworks. The Project Team calculates that the embodied carbon profile will result in over a 21% reduction in Global Warming Potential vs a comparable concrete structure.
6. Other Miscellaneous Sustainability Features. The Project is on target to achieve LEED Platinum certification. Other notable sustainability features include low-flow fixtures, an effective stormwater management strategy, potential to achieve significant reduction in Vehicle Miles Travelled (“VMT”), an optimized window-to-wall ratio, material selections, and modular kitchens and bathrooms. And importantly, thoughtful, well-crafted, and effectively implemented resident engagement programs, a core competency of NCLT, will facilitate the impact of these sustainability features.