City Light has recently implemented a new internal design practice for electric service connections of developments with four or more units. These properties will now be required to be served by underground infrastructure.
Frequently Asked Questions (FAQs)
The new internal design practice requires all new developments with four or more units be served by underground infrastructure. This is necessary while Seattle City Light evaluates and establishes construction standards for alternative solutions to meet the growing electric load demand in these developments.
Seattle City Light is adopting a new internal design practice to maintain safe and reliable conductor sizing for anticipated load growth. As electric vehicles (EVs) and electric heating/cooling systems become more common, the demand for electricity in new developments is expected to increase significantly. This new internal design practice addresses these demands by ensuring our infrastructure is sized appropriately to safely accommodate them, supporting the growing need for electrification.
Safety & Reliability
The new standards ensure that the cable and conductor sizing for new homes will meet the expected load demands, thus keeping infrastructure safe and reliable for years to come. New homes will be sized for future electrification, thereby eliminating or greatly reducing the cost of future upgrades.
Shorter Timelines
By providing a clear and consistent framework, developers will be able to plan more effectively, which can reduce service connection timelines and streamline the overall process.
We conduct annual reviews to ensure our service connection standards align with projected load demands, safety protocols, and infrastructure needs. This includes evaluating factors such as acceptable voltage drops, current-carrying capacity, thermal limits, and short-circuit protection, to maintain safe, reliable service.
The new internal design practice is set to be officially adopted on February 10, 2025. It will be included in the 2025 version of the Requirements for Electric Service Connections (RESC).
Once the updated RESC is published, Seattle City Light will follow up with stakeholders through existing communication channels. We will also check in with customers to assess their experience with the new design practice and address any concerns.
For more information or to discuss how these changes might impact your development, please contact City Light’s Engineering Team.