For our project, a new building is being constructed and connected to an existing district cooling chilled water loop. We are assuming that the central plant equipment must be included in the "base building" definition. The main central plant chiller uses ammonia, which is non-CFC and meets the prerequisite. This is the chiller that the new building is designed to use for cooling. However, there are two older CFC-based chillers in another building on campus. They are designed to serve the existing building where they are located, but are also connected to the chilled water loop. They can feed into the loop if the ammonia chiller is not running for some reason (like repairs). The College\'s planning and funding cycle will make it impossible to remove or convert the two older chillers by the time this new building is occupied, which would be required according to the wording of EA Prerequisite #3. Therefore, if the two older chillers must be included, this project cannot meet the prerequisite. Therefore, our question is: do backup/emergency chillers that are connected to the loop need to be included in the "base building" definition?"
Per the LEED 2.0 Rating System page 15, the "base building system" must not use CFC refrigerants to meet this prerequisite. If the primary, or base, cooling system is the central plant chiller, which uses ammonia, then the project meets the prerequisite. Emergency backup systems are not included in the prerequisite requirements. New buildings have no budget to effect the central plant, so there is a danger that we are setting precedent that all loop equipment must be CFC free and that the projects cannot effect this change. The response to this concern is that non-compliant loop equipment will be allowed as long as a phase out program is put in place that causes the change out to occur within 1 year of substantial completion. In your application, provide a system description and a sequence of operations that addresses when the older chillers would supply cooling to the stated project. Applicable Internationally.