Seattle City Light (SCL)
Public utility providing electrical power to Seattle, Washington, US, and parts of its metropolitan area. Seattle City Light is the 10th largest public utility in the United States and the first municipal utility in the US to own and operate a hydroelectric facility. The 800,000- residents (400,000+ metered customers) served by SCL use about 9.2 terawatt-hours annually. SCL was the first electric utility in the nation to become greenhouse gas neutral in 2005 and has the longest running energy conservation program in the country.
DNV GL is supporting Seattle City Light with site selection and owner’s engineering for microgrid deployment at a community center for resiliency. The microgrid will ensure that electric supply is maintained during emergency events and multi-day outages. The city’s centrally located microgrid will not only provide electric resiliency for the utility, but can serve as an emergency shelter for vulnerable customers, a community rallying point, or an emergency response team’s home base.
SCL’s clean microgrid will be based on rooftop Solar PV and a Battery Energy Storage System. During outage operation resources are controlled to maximize serving critical facility load. When grid connected, microgrid resources will manage export of firm renewable energy to the grid and provide distribution system load relief.
In the first phase of the project, DNV GL helped to select the appropriate site and technologies for microgrid deployment. DNV GL conducted electrical, civil and structural survey of potential sites, assessed safety and environmental requirements and recommended technology options. Detailed energy modeling of site operations was performed to determine optimal asset sizing as well as microgrid economic, sustainability and resiliency impact. DNV GL will create concept drawings, cost and schedule estimates to support procurement.
As owner’s engineers DNV GL will support procurement and provide technical support for permitting and approvals. In the design phase, DNV GL will review 30, 60, 90 and 100% design drawings created by the contractor. During construction DNV GL will provide construction monitoring, on-site quality assurance and function as PMO liaison.
Microgrid siting and deployment will maximize positive community impact, safety and reliability, ease of permitting and deployment, and increase sustainability.