Rating System

LEED BD+C: New Construction

Rating System Version

v3 - LEED 2009, v2 - LEED 2.2

Inquiry

This project involves the construction of a new refrigerated freezer warehouse. The overall facility is 140,000 sf. 105,000 sf is a -10 degree F freezer space, and the remaining area a +45 degree F freezer truck dock. There is a small office area, as well as support and maintenance areas. The facility operates as a distribution warehouse. Shipping and receiving logistical staff occupy the building. An automated material handling system means no people are in the freezer portion of the building. The facility is staffed 10 hours per day, 5 days per week; the refrigeration systems run continuously. A CIR was submitted on January 4, 2008, and responded to on February 4, 2008 for an earlier project being planned by the same building owner. This CIR builds on the previous response, and also raises some new questions. In the previous CIR, we defined a set of baseline parameters for areas not covered by 90.1 and indicated sources that support these assumptions. The reviewer requested specific documentation regarding baseline parameters and “industry standard practice”. Baseline Design In the previous CIR, the choice of refrigerant, compressor type, and capacity control method were based on “Customer’s Standard Practice”. The reviewer asked for more justification. Please confirm that the following will be acceptable. Refrigerant The baseline refrigerant in the previous CIR was R-22, although ammonia may be more widespread in facilities this size. However, the densely populated location and the local codes at the new site would require 24/7 certified ammonia operators. As the building will be staffed 10 hours, M-F, a 24/7 operator is not viable. The proposed building will use R-22 for these reasons. Can an R-22 system be the baseline? We will provide copies of the appropriate local regulations or other documentation to support this baseline assumption. Compressor Type and Capacity Control We are requesting confirmation that a letter from the refrigeration contractor stating that the customer’s choice of single stage rotary screw compressors with slide valve control to be industry standard practice is acceptable documentation. Automation within the Warehouse One of the most innovative aspects of the facility’s proposed design is fully automated material handling in the freezer. All the customer’s other facilities use regular forklifts. The automated material handling system provides energy benefits including reduced plug and infiltration loads. The greatest impact, though, is that the warehouse will be dark unless maintenance or repairs are required. We are requesting confirmation that it is acceptable to use a baseline that assumes human-driven forklifts, and that the warehouse would be equipped with fixtures that have a lighting power density according to AHSRAE 90.1 and operate on a schedule that is defined by usage of the warehouse. The proposed case energy model would be based on “lights out” operation. This saves refrigeration energy as well as lighting energy. In the office space, we will model occupancy sensors based on the 10% reduction in Appendix G Table 3.2. In the freezer truck dock, we will model the lighting as being controlled by an identical schedule in both the baseline and proposed designs. However, we are contending that a completely automated warehouse goes beyond occupancy sensor control, and are requesting confirmation that we are not limited to the 10% lighting reduction described in Table 3.2. Documentation will support the baseline assumption of an occupied, lighted freezer, and also show that the equipment in the proposed design will operate without the regular use of lighting fixtures.