Date
Inquiry

This project is located in Portland, Oregon. The intent of EAp2 is to establish a minimum level of efficiency for the proposed building and system, and we confidently believe we have met and exceeded the intent of the point, but have some limitations with regard to the ASHRAE standards for baseline energy use. We are constructing four greenhouses and an office room, all connected by a corridor, for a total floor area is 4385 sq. ft. Since the ASHRAE Standard 90.1-2004 does not apply to buildings or portions of buildings that use energy primarily for commercial or industrial processes, our project is proposing the use of a calculated baseline for energy use specific to greenhouses in order to maintain the integrity of the point while still including the greenhouse area in the certification process. The baseline we are proposing is the calculated energy use of a single pane glass greenhouse structure of the same size and dimensions with a U-value of 1.13. This baseline was chosen because single-pane greenhouses are the base model and most frequently purchased from the greenhouse manufacturer supplying our greenhouses. This project\'s greenhouses will use double wall polycarbonate with a U value of 0.65 or better. This baseline has been accepted for use by the State of Oregon Department of Energy\'s strict energy performance guidelines for the State Energy-Efficient Design (SEED) Regulation. The Oregon SEED rule requires that state buildings exceed local energy codes by 20% or more. The double-wall polycarbonate greenhouses will exceed this new, de-facto state baseline by 30%. Is our proposed baseline calculation for the greenhouses acceptable for meeting this prerequisite for greenhouses in lieu of ASHRAE 90.1? What are the submission requirements for this new greenhouses baseline and for the other energy efficiency component requirements of the standard?

Ruling

The project is requesting confirmation on their proposed alternative for determining the baseline case for a greenhouse. The proposed methodology is acceptable for meeting the prerequisite. However, this proposed baseline is not acceptable for EAc1, when calculating a percentage improvement in the building performance. Please note that USGBC has recently deemed the Oregon Energy Code 2005 equivalent to ASHRAE 90.1-2004 for LEED purposes (http://www.usgbc.org/ShowFile.aspx?DocumentID=2256). If this code is more appropriate, the project team may use it. Applicable Internationally.

Internationally Applicable
On
Campus Applicable
Off