Responsible Approach To Decarbonization in An Existing Building | P2S

Long Beach San Diego Los Angeles San Jose Irvine Seattle

Article Written By: James Del Monaco

Download Article

Fill out the form below to sign up for our mailing list and download this article.

Article Preview

Decarbonization in existing buildings presents many unique challenges and requires a well-thought-out approach to perform responsibly. The author recently presented a high-level approach to decarbonization in a campus setting in an Engineer’s Notebook column. This column will focus on the process of electrifying the hydronic heat-generating equipment in several buildings in a higher education setting.

Space heating needs have historically been met by using fossil fuels and combustion-based equipment to generate hydronic hot water. The primary generation equipment is generally inexpensive (boilers are ~$12–$30 per MBH), has high turndown (a number of manufacturers offer 20:1), and use an available, reliable resource for fuel. Building operators are familiar with operating and maintaining this equipment.

As we transition to electrifying the space heating system, heat pumps offer a viable option. Heat pumps have been commonplace in the industry for more traditional airside HVAC applications. More recently, heat pump technology is being used for hydronic heating applications and domestic hot water heating. Heat pumps have their own challenges, such as higher first costs, lower operating efficiency at higher supply temperatures and low ambient operating limitations.

Read Full Article ↓

Form has been submitted successfully!

Originally founded in Los Angeles in 1920 as a school of theology, Vanguard University moved to its campus in Costa Mesa, California in 1950. Over the century, Vanguard has evolved into a leader in educational innovation within its denomination, preparing students for all types of ministry. The University is now preparing for the next 100 years by ensuring generations of students have places and resources needed for academic, relational, spiritual and physical growth. P2S provided MEPT engineering design, site infrastructure, as well coordination for technology, AV and security design for the new state-of-the-art Waugh Student Center. The new building is an extension of the classroom, supporting a relational and unfettered approach to the learning environment of Vanguard.

The 35,000 GSF building replaces the existing student union and cafe, and now features a 16,000 SF cafeteria including on-site commercial kitchen facilities, a 3,000 SF fitness center and an 8,200 SF multi-purpose event space, as well as a student lounge which includes a fireplace and café.

During the schematic design phase, P2S reviewed program statements, site requirements and budgets with the design team, compiled the MEPT criteria and advised the team of the impact to the utility systems, code and space requirements. Designs were completed for the HVAC, electrical, plumbing, technology and lighting systems as well as site plans for proposed gas, electrical and telecom utility improvements, and recommended equipment location and orientation. Chilled water distribution infrastructure for connection to future developments was also designed. Sustainable design strategies were adopted to improve building performance.

During the design development phase, P2S updated and recompiled the preliminary designs as necessary and advised on space requirements and identification of major systems routing and updated site plans. P2S provided final construction documents which finalized the design and included system controls and construction details, reviewed cost estimates, implemented value engineering, constructability design revisions, and City plan checks. Additionally, our team provided construction support and close-out documents. The project was completed in early 2020.

The new Student Success Center (SSC) at UC Riverside (UCR) is a 3-story, 62,000 GSF building comprised of general assignment classrooms for modern pedagogies and technology, multi-purpose student life spaces, and dining services. The building is intended to serve as a new beacon on the campus to support student and organizational success through active learning, collaboration, and community building. The project was intended to not only address UCR’s continued student growth and corollary shortfall of instruction space, but to do so in a manner that upholds UCR’s academic mission with an emphasis on reinforcing student success. This project was certified LEED Gold on July 28, 2022.

From a sustainability standpoint, the team coordinated the construction materials to minimize loads within the building and choose climate appropriate solutions. These collaborative efforts allowed the team to minimize the infrastructure and maximize the usable square footage within the proposed footprint. The team worked to analyze every hour of operation to right-size the equipment and provide innovative solutions, some of which had not been utilized on the campus yet. To implement these systems, the team provided examples of where these technologies had been utilized for similar building types and clients. The building also features low-emitting materials that minimize concentrations of chemical contaminants that are damaging to indoor air quality, human health, productivity, and the environment.

Advanced energy modeling techniques were performed to evaluate the impacts of various energy conservation measures (ECMs). The project team evaluated the energy use intensity (EUI) impacts of multiple design strategies and integrated them with cost estimating from the contractor to understand the total benefits of the ECMs. In a number of cases, the team opted to move in a different direction. For those strategies that were employed, we used the following techniques:

-The project has several large lecture halls with occupancy ranging from 100-420 occupants, based on the room size. These lectures hall have high ventilation loads and raised flooring. For these spaces, we used indirect evaporative cooling and displacement ventilation to reduce the demands on compressor driven cooling. These strategies resulted in an EUI savings of approximately 4 btu/SF-year.

- For the large lecture halls, we provided four VAV zones, with the zone controls and reheat coils within the mechanical penthouse. This allowed us to eliminate any service within the space or the raised floor, to minimize the maintenance impacts to the space.

- The campus had an existing steam system that is failing and unreliable. The campus also has a requirement that we cannot have combustion for hydronic heating and domestic hot water. We used a modular heat recovery chiller to generate HHW for the building and export CHW to the campus loop. This strategy had a 7-point EUI reduction compared to the steam system.

- The project utilized a heat pump water heater for domestic hot water.

These solutions would not have been possible without collaboration of the building layout, envelope construction, shading, etc. to minimize the loads seen by the mechanical system. The contractor supported this collaboration by providing valuable input into the cost impacts of the strategies being proposed.