Snohomish County Public Utility District No. 1

Skip navigation and go to content

Customer Service (M-F 8a-5:30p): 425-783-1000

Frequently Asked Questions

View all
What is geothermal?

Geothermal power (from the Greek words geo, meaning earth, and therme, meaning heat) is energy generated by heat stored beneath the Earth's surface. Prince Piero Ginori Conti tested the first geothermal generator on 4 July 1904, at the Larderello dry steam field in Italy. The largest group of geothermal power plants in the world is located in The Geysers, a geothermal field in California. As of 2007, geothermal power supplies less than 1% of the world's energy.

How does it work?

The energy source captures the heat from the Earth – in the form of hot water or steam – and extracts it to drive a turbine and generate electricity. It’s a well understood technology that’s improving all the time. Countries all over the world have tapped the energy source, most notably Iceland, China and Mexico, but the U.S. leads the world in overall production.

Why is this region attractive for geothermal energy?

Snohomish County encompasses a broad swath of the North Cascade Mountain Range including the Glacier Peak volcanic region and numerous hot/mineral springs. This general region has been recognized as an area of geothermal potential for many years, but no extensive geothermal exploration has ever been conducted.

How big would the plant be?

At this point the PUD is involved only in exploration, and has made no commitments to future development. Even should testing prove the site has development potential, a great many factors would have to be analyzed before any decision would be made to pursue such development, and any such development would be the subject of a public process. Additional drilling would have to be conducted in the coming years to determine if a suitable reservoir exists and what type/size of plant could be supported. Very limited current data suggests perhaps a 20 MW plant.

The image below shows the footprint of geothermal energy facilities compared to that of other energy sources.

Since the Garland site is not being developed, how will the site be restored?

The temporary construction pad and drilling materials will be removed from the site, and the site will be restored in accordance with permitting requirements and the interests of the property owners. The improved access road will remain in place.


Adam Lewis
(M-F, 8am to 5pm)