District Energy

Location: throughout Overlake Village
Project Phase: feasibility study
Timeline: feasibility study completed
Contact: Jeff Churchill, Senior Planner, 425-556-2492

Feasibility Study Conclusions

District energy systems are highly efficient ways of heating and cooling buildings using small central plants connected to a network of underground pipes that carry hot water, chilled water, or steam to multiple buildings. Not only does district energy require less fuel to operate, but it also balances energy demand between buildings on the district grid, reducing costs and carbon emissions.

The City evaluated district energy for Overlake Village in a two-step process: a prefeasibility study completed in late 2013 that was funded by a Department of Housing and Urban Development grant, and a feasibility study completed in December 2014 funded significantly by Puget Sound Energy.

The feasibility study found that there were potential economic and environmental benefits to establishing a district energy system in Overlake Village; however, the benefits do not appear sufficient to offset the one-time and ongoing resources it would take for the City to be the primary entity to launch and maintain a new utility considering the City's existing service responsibilities and other strategic initiatives underway.

A pilot project on a campus-style setting might be a more feasible application, where property control is of single-ownership. Additionally, the City will explore other ways to achieve community carbon footprint reduction in alignment with the Climate Action Implementation Plan. For example, there may be possibilities to transition new multifamily construction from electric to natural gas heating.

How District Energy Works


How DE Works

Green Energy Incorporation

The district energy grid provides ample opportunity for fuel switching and adding other green energy technologies.

Green Infrastructure


2014 Feasibility Study Report
Staff Report to City Council (Jun 2, 2015)
2013 Pre-Feasibility Study
District Energy Fact Sheet

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