NRG DOWNTOWN DISTRICT PLANT
SAN DIEGO CA
Beginning in 1999 Tanner Engineering was retained to perform master planning and electrical design drawings for a project to increase the capacity of the downtown district co-generation plant by 400%. Because horizontal expansion of the property was not a possibility, all of the added equipment for the plant upgrade had to be contained within the same footprint area. This resulted in a complex internal mezzanine design. In 2003, Tanner Engineering, in a continuing partnership with NRG designed the re-configuration of site utilities to accommodate the construction of the Tower at 655 Broadway. Extensive and detailed planning for all of the projects enabled plant operations to be maintained throughout all phases of construction. Tim Newburn, as project manager, was in charge of managing phase one of the project including the installation of a 2500-ton York OM chiller driven by a 1.5 MW Saturn Solar turbine. Phase 1 also included the installation of roof-top cooling towers, an absorption chiller, and extensive foundation work and steel superstructure required for the chiller, engine, towers and platforms.
Phase 1
- Plant expansion project increased capacity from 3000 tons to 12,000 tons.
- Cable tray system designed to support pumps and motor control centers above existing distribution and chillers.
- Capacity expansion of the plant carefully sized and planned resulting in the 100% utilization of the existing dual 4160V services.
- Total design and construction period took only 8 months to complete.
- Project Cost: 17 million
Phase 2
- The existing SDG&E substation feeding the plant was required to be removed to accommodate the construction of Broadway 655. Design of a new customer owned substation within the plants existing boundaries was required.
- Design of a mezzanine structure to split the new 7.5MW unit substation so that sufficient area was maintained for the addition of future plant equipment.
- Project Cost: 1.5 million
Phase 3
- Re-configuration of the 12kV utility loop to support the new tower on Broadway.
- Demolition of the old 4160v utility substation.