Page 82 - Designing for Zero Carbon - Case Studies of All-Electric Buildings

CASE STUDY NO. 3 KAISER MEDICAL OFFICE BUILDING
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Care Team collaboration office with electrochromic glazing in windows..
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Designing for Zero Carbon: Volume 1
Post Occupancy: Observations and Conclusions
The building was occupied in June 2018, with the on-site solar PV system coming fully online in September of that year. Normal occupancy continued until the spring of 2020, when the pan- demic caused changes in occupancy patterns and system operations. In this period, there has nevertheless been good opportunity to observe the functioning of the building systems and user behaviors. Among these, the most noteworthy is the commissioning issues that arose in this first year of occupancy, which are discussed below.
Remarkably, with regard to energy use, this all-electric building has achieved all the project goals, including an EUI = 35 and zero-net-energy performance.
Post Occupancy: Integrated Design Process
The involvement of a construction management firm / general contractor in the design phases was regarded as very positive for a cost-based design process. This ensured that accurate infor- mation was available when considering alternative design strategies.
Post Occupancy: Solar PV System
The use of a solar PPA is highly successful on this project with regard to cost, maintenance and performance. A zero-net-energy building requires the first-cost investment in a solar PV system large enough to offset the annual energy use. For most clients, this can be a large added first cost. But the PPA solves this cost issue—no first cost incurred and electric energy costs currently less than that supplied by the public utility. This is a common experience across many building types, particularly if the client is a non-profit and is not eligible for the sizable tax rebate.
Post Occupancy: Commissioning and Controls Systems
According to the design team, the biggest challenge was coordinating the controls systems de- sign and commissioning. Commissioning should be completed before the building is occupied so that the building systems are operating correctly when the occupants first experience the build- ing environment and its controls. Unfortunately, the building was occupied as the commissioning work commenced, so that control system malfunctions were the intial occupant experiences. These negative experiences were compounded by high turnover in the commissioning firm’s staff, resulting in poor coordination with Kaiser maintenance staff.
These issues were ultimately resolved, but the frustration of the users and maintenance staff with the building systems lingered for some time afterward. In fact, the unconventional approach to the building systems design was perceived as the cause of the time required to commission the controls systems properly, when in fact the installed systems are less complex than those conventionally used.
It is highly recommended, especially for projects that utilize an integrated design process, that the controls system subcontractor who will be responsible for the building commissioning partici- pate in the later design phases as well.
Post Occupancy: User Behavior
A User Manual was not created, which might have mitigated the issues encountered during the belated commissioning experience. Also, for example, the use of thermafusers was not known to the users, so they were not aware of their ability to control their individual space temperature by varying the air mix via this room device.