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HomeMy WebLinkAbout2025-05-01-PBC-min.pdfTOWN OF LEXINGTON Permanent Building Committee Permanent Members Jon Himmel, Co-Chairman, Charles Favazzo, Co-Chairman, Peter Johnson, Celis Brisbin, Elizabeth Giersbach, Frederick Merrill, Ian Adamson Associate Members: Wendy Krum, Henrietta Mei PBC Minutes for the meeting held on: 5-1-25 Meeting was held hybrid via Zoom Members Present: Jon Himmel, Celis Brisbin, Wendy Krum, Frederick Merrill, Elizabeth Giersbach, Ian Adamson, Chuck Favazzo, Wendy Krum Others Present: SMMA: Lorraine Finnegan, Andy Oldeman, Martine Dion, Anoush Krafian, Michael Dowhan, Anthony Jiminez, Brian Black, Andrew Elliot Dore & Whittier: Christina Dell Angelo, John Albright, Mike Burton Turner Construction: Jamie Meisner Staff & Others: Dr. Julie Hacket, Mark Barrett, Mike Cronin, Maggie Peard, Kathleen Lenihan, Cindy Arens, Tom Shiple, The PBC meeting was called to order at 6:00 pm. Discussion with LHS Project Team on Review/Recommendations on confirmation Items being proposed to SBC: HVAC System Confirmation Andy Oldeman and Martine Dion, with SMMA, discussed the HVAC system selection process and recommendations. Four different options were examined, which included central Ground Source Heat Pump (GSHP), central Air Source Heat Pump (ASHP), a hybrid system, and ASHP/VRF that relied on distributed refrigeration throughout the building. The hybrid source (option three) was the recommendation, and it was compared to the air source option (option two). Option three met the EUI goal of 25. The equipment life was longer for the hybrid source. It was noted that the ground wells used were 126 for the hybrid source, compared to 225 wells used in the ground source. The hybrid source was considered more reliable. The heating rate was asked about, and it was noted that the goal was 105 degrees. It was noted that Sustainable Lexington preferred options two and three over options one and four. The Integrated Design & Construction policy design required a total life cycle cost analysis, and how each decision affected other parts of the building was examined. There were three scenarios for the IRA (full, solar, or hybrid), all of which were modeled. Twelve scenarios in totaled were modeled, which included modeling against the debt service and operating costs. Two of the scenarios rose to the top: ASHP Longspan Solar and Hybrid Longspan with Solar. The total expected cash flow was $99 million for ASHP and $91 million for hybrid. The impacts of Eversource charges were discussed, which were linked to capital costs and would be applied to the operating budget. The positive cash flow was the cash flow after the loan and debt service were paid for. The HVAC savings after Mass Save, compared to the baseline gas/chiller, were presented. With the Mass Save incentives, the ground source heat pump would be $9 million less than natural gas, the air source would be $22 million less, and the hybrid would be $15 million less. If Longspan was added, the air source was still net negative, and the hybrid was positive. For debt service payments, the air source was the best. For Eversource payments, ground source had the lowest payment, followed by hybrid, air source, and VRF. There were only minor changes in solar, peak demand, and AECs. The comparison of space requirements, efficiency, and incremental operational carbon was presented, which showed that the hybrid was the best option. The domestic hot water ground source heat pump option was a good and reliable option. It would amount to two or three additional wells. The other mechanical options were discussed, and it was noted that the ground source was more compact and reliable. The locations of the additional wells were discussed, and options included the new or existing parking areas. It was discussed that the hybrid source was preferred due to the ability to have the domestic hot water ground source option. Jon Himmel made a motion to recommend option three to the SBC with the domestic hot water ground source option. Chuck Favazzo seconded. The motion passed unanimously. Renewable Energy Discussion The location of the battery was presented, which would include three containers of batteries with a two -megawatt eight-hour capacity. The list of equipment was reviewed, and it was noted that it was built against a blank wall of the auditorium. It was asked what would happen if the ground wells were to shift. If the ground wells shifted, the mechanical room could be moved, but the electrical would remain in the planned location. Wendy Krum asked how far above ground level the containers were. It was reported that it was a six-inch pad, and the containers were six to eight feet tall. They were looking into connecting the pad to the loading dock. The bylaws required 4% EV charges, and up to 50% of the parking spots had to be enabled for future EV charging. An estimated 92,000 kWh would be used for 4% of spots and 838,000 kWh for 50% of spots having EV charging. Maggie commented that the numbers were more in line with what was seen in Lexington, but she noted that there were still substantial increases in usage year-to-year. The utilization rate and changes over time were discussed. The planned 20 EV spaces were discussed. Charging a fee for people to charge their vehicles was discussed. Regardless of whether electricity was charged for, Eversource would still charge. Site Design Introduction & Discussion The goals, process, and program for the site design were presented, and it was noted that resiliency and sustainability were included in all of the goals and decisions. Students, faculty, and staff were spoken with throughout the process, and the responses were taken into consideration for the site design. The results of the solar studies from August through June were presented. Circulation of people around the school and programming for the various spaces were all considered during site design. The feature space designs included outdoor learning environments that would allow for spaces for classrooms, an area in the main entrance plaza for students to be picked up, and a new quad area in the east entrance plaza. The inclusion of landscaping was discussed. Cindy Arens asked about bike parking, and it was confirmed that the bike racks would be present throughout the site. Information on the spaces for the number of buses was requested. It was reported that there would be room for 18 or 19 school buses around the loop and six on the street. The use of parking lots after hours was discussed. The parking was broken up to be more accessible to different programs and areas of the school. The scale comparison, space preview, design process, and overall concept of the roof design were presented and discussed. In terms of diagramming, the common movements included main entrance doors on the west and east and light in the center. There was also coordination with skylights, and there was flexibility with the location of the skylights. Each of the conceptualizations worked to achieve the same goals. It was asked what programming was on the fourth floor above the entry. It was reported that there were two classrooms. Jon Himmel commented that there appeared to be no differentiation among the three walls of the large Commons area and that it could be more exciting. It was reported that there was an exterior glass wall on the west side, which would provide light. Jon Himmel discussed bringing in more light. The location for students to eat lunch was discussed, and it was noted that it was not intended for students to eat lunch on the roof terrace. The terrace could be used for students’ free blocks, art, and other activities. On Monday, May 5, additional information will be provided. Public Comment There was no public comment. Summary of any action items The traffic circulation slide will be incorporated into the presentation on site design for the meeting on Monday, May 5. The percentage of hardscape to landscaped space on the three site design options would be provided on Monday, May 5. Urgent Business There was no further business. Motion to adjourn PBC, all approved.