ID#2540 made on
EAp2 - Minimum energy efficiency performance
LEED O+M: Existing Buildings
Our project building is a 5,900 square foot Chapel located on a University campus. It has an unique schedule, use, and amenities, including an indoor botanical garden and koi pond. The project team ha...
Our project building is a 5,900 square foot Chapel located on a University campus. It has an unique schedule, use, and amenities, including an indoor botanical garden and koi pond. The project team has attempted to create an energy use baseline for the building in Portfolio Manager; however, the Chapel does not match a classifiable space type. Research efforts to find a comparable building with a similar layout, schedule, use, and amenities, have proven difficult. For these reasons, the project must submit under Option C2 for Energy and Atmosphere Prerequisite 2. Under this path, the project building collects 3 years of historical energy use data, creates an average energy use index baseline, and compares it to the average energy use from the past 12 months that ends with the conclusion of the performance period. The Chapel has a separate meter for each of the following: electricity, steam, chilled water, and water. The Chapel is connected to a central campus steam plant and a central chilled water plant for heating and cooling, respectively. The Chilled Water Plant is actively used during winter months, and is monitored by a third party engineering firm, which manages a server to trend individual building usage data. This past winter, the Chilled Water Data server crashed, and the historic chilled water usage for each building on campus was lost, including the chilled water data for the Chapel. The server has been repaired and data will be collected from February 2009 through the end of the performance period, May 2009. According to a past credit interpretation request (CIR) for EA prerequisite 2 from September 8th, 2008, a building must report, "A minimum of three months of metered performance period energy consumption data at the individual building level." The length of time for reporting the chilled water data will be four months in duration so the project will meet the precedent set in that CIR. The second portion of submittal path C2 is to create a historical energy use baseline for the project site. Unfortunately, as a result of the server crash, all historical chilled water data has been lost. The project team proposes meeting the requirements of EA Prerequisite 1 as follows: 1. The project team will track chilled water consumption from February 2009 through May 2009 and record the number of cooling degree days during that time period. 2. The team will then use the ratio of chilled water usage to the number of cooling degree days within these four months to extrapolate chilled water usage for the performance period calendar year. 3. The project team will assume the same chilled water consumption in each year of the historical baseline, effectively not taking credit for any of the recent energy conservations measures that will reduce chilled water usage in the most recent year. This proposed path will take no credit for chilled water savings, but allow us to demonstrate a 20% savings through a reduction in EUI from electricity and steam use. We appreciate any feedback on our proposed approach to creating an energy use baseline in this building where one set of utility data has been irretrievably lost and welcome alternative suggestions.
The CIR referenced from September 8th, 2008 was filed under LEED for Existing Buildings v2.0, which has less stringent energy benchmarking data requirements than LEED for Existing Buildings: Operations & Maintenance v2008. For LEED for Existing Buildings: Operations & Maintenance v2008 projects, the LEED performance period for EA Prerequisite 2 and EA Credit 1 must be 12 consecutive months in duration (extrapolation of 3 months of data is generally disallowed). Given the extenuating circumstances, the project team may collect less than 12 months of data for chilled water only provided the following conditions are met (all other energy types must include 12 months of data): 1. Chilled water data must be collected for a performance period of at least 6 months 2. The 6 months for which chilled water data is collected must include the 4 months of the year with the highest number of cooling degree days, based on historic averages for the project's location 3. The 6 months for which chilled water data is collected must fall within the same 12-month period during which performance period data is collected for all other energy types 4. For the remaining 6 months of the energy performance period, chilled water data must be estimated based on cooling degree data for that specific time period so that a full 12 months of data for all energy types is accounted for. Upon establishing 12 months of data for all energy types for the performance period, use the Energy Star Portfolio Manager Tool to develop a weather normalized source EUI for both total energy consumption and just chilled water consumption (as described in the Option B and C Calculator for EA Credit 1 and the LEED for Existing Buildings: Operations & Maintenance Reference Guide). For each historical year, add the chilled water-only value to the Weather Normalized Source EUI generated by Portfolio Manager for all other energy consumed during that year to complete Section V of the Option C Tab in the Option B and C Calculator for EA Credit 1). This approach is similar to that proposed in Step 3, but accounts for converting usage data into the weather-normalized Source EUI value that benchmarking is based upon. To document the approach, provide transparent data showing that each of the conditions above is met and that protocol for integrating chilled water data into historic years was followed. Applicable Internationally.
Related Addenda (Corrections & Interpretations)