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HomeMy WebLinkAbout2024-09-17-SLC-minSustainable Lexington Committee Minutes of Meeting of September 17, 2024 A meeting of the Sustainable Lexington Committee (SLC) was held by Zoom conference. A quorum of seven was present throughout. Members Present: Cindy Arens (chair), Celis Brisbin, Lin Jensen, Andy Joynt, Rick Reibstein, Todd Rhodes (vice-chair), Dan Voss, Members Absent: Paul Chernick, Charlie Wyman Staff Present: Maggie Peard (Sustainability & Resilience Officer), Mike Cronin (Department of Public Works), Melissa Battite (Recreation Department) Other Attendees: Mark Sandeen (Select Board), Joe Pato (Select Board and SBC), Andy Olderman (SMMA), Brenda Lam (SMMA), Martine Dion (SMMA), Kseniya Slavsky (SBC), Erica Downs (TGE), Charles Hornig, Jacob Greco (D+W), John Albright, Matthew Rice (SMMA), Sebastian Fairbairn, Sophie Shaw (SustainabLY), Tina McBride, Ricki Pappo, Bijan KHosraviani. Cindy called the meeting to order at 6:05 pm and polled the SLC members to ensure that they could be heard. SMMA staff walked the committee through a presentation to provide an overview of the status of sustainability initiatives associated with the Lexington High School project. •Comments captured during the presentation include: ▪Mathew Rice commented that LEED Gold would be achieved based only on Lexington IBDCP and bylaws. Martine Dion added that some LEED points are required by MSBA (IAQ, some materials, etc.) and would result in additional MSBA funds. ▪DPF has provided the Police Station red list evaluation. SMMA is adding that list to their own list. SMMA will come back with proposed recommendations. ▪Martine Dion commented that estimates for paybacks for high efficiency electric HVAC systems are around 1 year or less with incentives. ▪Regarding solar installations, new construction has a larger gap in PV because the buildings have less roof space. The in-place options have less canopy space over parking. ▪Regarding IAQ and the target to reach the 600ppm CO2 target, Andy Alderman commented that air exchanges rise exponentially as CO2 ppm levels get to 600, Sustainable Lexington Committee Minutes of September 17, 2024 potentially increasing the required performance and cost of the HVAC system. No estimates have been made at this point. ▪The review of the Life Cycle Cost Assessment (LCCA) included the following comments: -A working group of SMMA, staff, and SLC representatives is needed to improve the analysis. The IBCDP calls for an iterative process of LCCA. -The LCCA is currently working with monthly data and needs to consider hourly data. -The LCCA should include a deeper analysis of solar generation in the winter. -The analysis needs to determine the battery storage size to provide enough capacity to meet site needs. -Need to determine what baselines to use for comparisons. ▪The initial, conservative assessment is that the planned HVAC and solar systems will result in annual operating cost savings of $450k to $600k. Following the presentation, a question and answer session was initiated. The following summarizes the discussion by topic. •IAQ: ▪Mark Sandeen recommended that SMMA meet with the Board of Health (BOH) to discuss the 600ppm CO2 target and commented that they could help to find a sweet spot for the planned performance. Martine Dion agreed that that makes sense. •LCCA: ▪Mark Sandeen recommended that the analysis consider low, moderate, and high scenarios. Martine Dion said that she like the idea. He also commented that the scenarios will be affected by the decisions related to ground source heat pumps (GSHPs). ▪Cindy Arens commented that heating and cooling loads, peak load data, geothermal performance and solar efficiencies, should be looked at by the sub group so that everyone is aligned on the assumptions and making the best choices based on that information. ▪Cindy Arens commented that SMMA should be tracking opportunities for grants even if they are uncertain at this point so that we don’t lose track of them. ▪Cindy Arens commented that it’s been difficult getting 15 min interval data from Eversource, but we need that data to do the analysis. Martine Dion said that SMMA will be working to get that data. .2 Sustainable Lexington Committee Minutes of September 17, 2024 ▪In response to a question from Lin Jensen, Martine Dion said the total operational savings estimates are based on the new square footage. •Battery Storage: ▪Mark Sandeen commented that storage is not so much needed for resilience (powering the building during an outage), it is more for reducing peak demand charges and to support interconnection to the grid (reducing the effective size of the system from the utility’s perspective). •Embodied Carbon ▪Cindy Arens asked about embodied carbon and Martine Dion said that SMMA would be about to address that analysis at the next meeting. ▪Lin Jensen asked whether SMMA is considering embodied carbon of temporary classrooms? Is there swing space somewhere else in town that could be used? -Matt Rice replied that the temporary classroom suppliers have existing buildings that can be reused, reducing the embodied carbon impact. Running some grades/classes in other sites is not preferred for educational purposes. They only do it in dire situations. ▪Lin Jensen asked about the cost and embodied carbon impact on fields. -Matt Rice confirmed that those types of issues are being considered. •Solar: ▪Mark Sandeen commented that the electricity will be considered Mass Class I RECs (Renewable Energy Certificates). ▪Dan Voss commented that SBC is discussing tradeoffs of footprint and parking regarding solar, but we need to start showing where the solar gaps (e.g., 0.7 MW) will be on the site. -Martine commented that SMMA is looking at closing the gap by adding solar vertically on the buildings and other novel approaches. -Dan said that the concern is that these approaches are not economic. The community needs to be given the option of seeing where additional solar on the site (ground and roofs). The aesthetics conversation needs happen at the same time that the costs are considered. -Martine added that SMMA plans to look at both. The majority of parking has arrays. Also looking at walkways. Plus, the canopies provide benefits of shade on the ground and on roofs over equipment. -Dan stated that LHS needs to be a net-zero building and filling the gaps with RECs from external sources will not be acceptable to the community. .3 Sustainable Lexington Committee Minutes of September 17, 2024 -Dan added that a solar designer could develop actual solar designs for each of the concepts – they don’t need to be conceptual. You could show where things like where ag-solar systems could be used over green space. The community needs to see what the solar will look like from day one. -Martine replied that she will take this back to the team. Solar Design Associates can do that analysis. -Kseniya Slavsky (SBC) said that she supports Dan Voss’s comments and she supports the priority of solar over aesthetics. •EV Charging ▪Dan Voss stated that the analysis needs to consider the impact of EV charging. ▪Martine Dion commented that the SBC agreed that EV charging demand is not included in the net zero assessment of the building. Dan challenged that statement and Martine offered to find it in the SBC meeting notes. Dan added that the community should decide whether EV charging needs to be included. ▪Kseniya Slavsky (SBC) said that she did not remember that the SBC agreed not to include EV charging in the site demand load. •Passive House ▪Bijan KHosraviani asked whether the buildings going to Passive House (PH). -Martine Dion commented that the buildings will be close to PH, but they are not looking at PH certification. They looked at it and it was costing about $1 million and considered not be worth pursuing. -Bijan asked if SMMA considered the reduction in the mechanicals that you would require and the amount of solar that would be needed. -Martine replied that yes, SMMA considered those impacts in this costing and shared the project goals with passive house experts for review. -Bijan commented that PH ranges from cost neutral to 2% more expensive. Martine agreed. -Cindy Arens added that with the approach we are following, we should get close to PH performance. •Air to Water Heat Pumps ▪Bijon BHosraviani asked whether SMMA is considering air to water heat pumps. ▪Martine replied that air to water are available, but require more space and have not yet been discussed as an option. They have looked at them on other projects and they are costly. They have not been ruled out yet. That will be in schematic design. .4 Sustainable Lexington Committee Minutes of September 17, 2024 •Building Energy Performance ▪Kseniya Slavsky (School Building Committee – SBC) asked about the repercussions of not meeting the 25 EUI target. -Martine Dion replied that SMMA is in the very, very beginning of the analysis. SMMA does not yet have the details to do a detailed analysis. Once we get into schematic design we will have a better estimate. That said, Martine added that Arlington had a 25 EUI goal and beat that goal. -Martine added that Eversource/MassSave provides about $2/sf for 25 EUI but it drops if you don’t hit that target (e.g., $1.5/sf over 25). -Martine said that SMMA is pretty confident that 25 EUI can be achieved. •General Comments ▪Kseniya Slavsky (School Building Committee – SBC) said that there are many sustainable elements that are being considered. The SBC has a limited purview on these issues. It would be helpful if SLC could provide input to SBC. ▪Lin Jensen added that the IDP requires that the building have dishwashing facilities suitable to handle washing/drying of reusable food ware (trays, cups, utensils, etc.) Cindy Arens summarized the next actions with the following points: •Embodied carbon will be addressed at the next meeting with SMMA. •SMMA should set up a meeting with the BOH to discuss IAG targets. •Scenarios should be included in the LCCA •Sub groups should meet again to address specific issues. •She also reminded the group of tomorrow’s community meeting. Next Meeting: The next regularly scheduled meeting of the Sustainable Lexington Committee we be held in October. The date and time has not yet been determined. The committee voted to adjourn at 7:55 pm. Respectfully submitted, Todd Rhodes .5