ID#2382 made on
EAc6 - Green power
LEED BD+C: New Construction, LEED BD+C: Schools
Our project is a science and technology laboratory building in the city of Port St. Lucie, Florida. An Energy Cost Budget calculation has been done for the project to meet the requirements of EA Prere...
Our project is a science and technology laboratory building in the city of Port St. Lucie, Florida. An Energy Cost Budget calculation has been done for the project to meet the requirements of EA Prerequisite 2 - Minimum Energy Performance. The project is not seeking EA Credit 1-Optimize Energy Performance. Under the LEED Reference Guide EA Credit 1 "a model using the Energy Cost Budget method will NOT be accepted for credit under EA credit 1", therefore it won't be accepted for EA Credit 6. The alternate methodology is to use the DOE-CBECS survey. Laboratory buildings are part of the 'other' category with a median rate of 13.8 kWh/square foot. It has been our experience that a building functioning as a laboratory uses significantly more electricity per square foot. In a CIR ruling on 2-04-2008 under LEED EB, it reads, An alternative approach for your laboratory building would be to use the Energy Benchmarking Tool available through Laboratories for the 21st Century (Labs21), which is a resource co-sponsored by the EPA and DOE for the design, construction, and operation of laboratories. The Energy Benchmarking Tool can be found here: http://www.labs21century.gov/toolkit/benchmarking.htm. Using the metrics provided by the tool, calculate your project's percent reduction in energy use compared to the benchmark. You can then calculate the corresponding number of LEED points. Because this project does not currently fall into a benchmark region in the Labs for the 21st Century's Energy Benchmarking Tool, an electricity rate of 40.1 kWh/square foot as determined by the aforementioned tool has been recommended. If this methodology is not acceptable to the USGBC, please advise on a desired approach to estimating energy used for laboratories.
The project team is requesting clarification regarding the methodology for determining the electric energy consumption of a laboratory building in order to determine the amount of green power to purchase for the project. The project has completed an Energy Cost Budget model (Chapter 11), but has not completed a Performance Rating Model (Appendix G). The project team should use the proposed case electric energy reported for the Energy Cost Budget modeling method. Per ASHRAE Energy Cost Budget method modeling requirements, all systems and process energy should be reflected in the model. Therefore, the proposed case model results should be very similar (if not identical) to those reported for Appendix G. Therefore, it is acceptable to use the Proposed Case Model from the Energy Cost Budget Method to reflect total building energy performance for EA Credit 6. It does not appear that sufficient information is available in the Labs for 21st Century Energy Benchmarking Tool to provide a valid determination of building energy consumption for this project. As indicated by the project team, the project does not currently fall into a benchmark region in the Energy Benchmarking Tool, and at the date of this CIR Ruling, only 131 laboratory buildings were included in the benchmarking database nationwide. Since there are no buildings benchmarked in the location where this project is located and since there is such a small subset of buildings nationwide, it is not acceptable to use this tool as a measure of total building energy consumption for this project. Applicable Internationally.
Related Addenda (Corrections & Interpretations)