Yes! Energize Eastside will improve the reliability of the Eastside's transmission system to help keep the lights on under stressed conditions.

Additionally, the last major upgrade to the backbone of the Eastside’s electric grid was in the 1960s. Since then, the Eastside’s population has grown eight-fold, and our economy depends on reliable power in ways that it did not 50 years ago.

Federal regulations require PSE to have sufficient infrastructure to meet foreseeable demand requirements or plan for intentional load shedding (also referred to as rolling blackouts or rotating outages) to customers. The Energize Eastside project will provide the necessary infrastructure to meet federally-mandated requirements. Energize Eastside builds a new substation and upgrades existing transmission lines to ensure the system can reliably serve our growing communities.

Learn more about Eastside need and solution.

Yes! On the Eastside, peak customer electric power demand—the amount of energy used at one moment—has been growing dramatically in recent years. We see the highest demand peaks, on cold winter evenings and hot summer days when more customers use air conditioning. And we have more customers than ever before driving those demand peaks. We need to act now to minimize the risk to the electric grid and Eastside customers. Until Energize Eastside is built, some scenarios may force us to use corrective action plans to protect the integrity of the grid and ultimately the reliability of service to customers. Those corrective action plan include the uses of load shedding.

Yes! A total of six studies — including two conducted by independent experts hired by the City of Bellevue and the Cities' EIS project team — have confirmed that we need to upgrade the Eastside’s electric grid now. More recently, in 2020, a study was commissioned by the City of Newcastle. That study also concluded that the project is needed to comply with reliability standards. Learn more about project need.

PSE’s planners and engineers analyzed a variety of approaches to address the Eastside’s growing energy needs, including reducing demand through conservation, increasing the capacity of our existing transmission lines, generating energy locally, and building new infrastructure. After a comprehensive review, PSE and independent experts determined that a combination of continued conservation and infrastructure upgrades – a new substation and higher capacity transmission lines – is the best way to reliably meet the Eastside’s growing energy needs.

We've looked at many ways to solve the Eastside's electrical problem. We studied whether the Eastside’s electrical needs could be addressed with other alternatives rather than building new infrastructure. Read the solutions report and the non-wires solutions analysis to learn more about alternatives that were analyzed.

Both Phase 1 and Phase 2 of the Environmental Impact Statement (EIS) process studied project alternatives. For more information about the alternatives studied, visit EnergizeEastsideEIS.org.

After nearly four years of study and extensive dialogue with Eastside communities, PSE selected the existing utility corridor “Willow 1” route as the final route to permit for Energize Eastside in 2017.

PSE evaluated multiple route options and selected the existing corridor because it is the least impactful route to Eastside communities. Our decision to use the existing corridor was guided by two key factors:

• Our commitment to safety. The project will be built and operated to the highest safety and engineering standards. Using the existing corridor, along with optimized designs and operations, the project can safely co-exist with the Olympic Pipeline.
• Our commitment to limit impacts to the environment. This route affects the fewest number of trees and avoids the construction of new corridors. We know our customers value trees. Our goal is for there to be more trees when the project is complete, not fewer.

Learn more about the final route.

We began construction of the Richards Creek substation in September 2020 and on the transmission lines in Renton in 2021.

Energize Eastside will be built in phases, depending on the permitting timeline in each city.

As we get closer to construction in each city, we'll inform the local community of additional details and timing. Visit the Construction page to learn more.

Conservation is a key component of Energize Eastside, and we anticipate that customers will partner with us to meet our conservation goals. However, conservation alone is not enough to keep up with our region's growth. PSE works hard to encourage our customers to conserve electricity. However, our conservation programs are voluntary – it’s the customer’s choice to make a change. Our Eastside economy and population are growing far faster than our conservation efforts can keep up with.

Learn more about the Eastside’s electric need.

The Eastside’s electric transmission system was built in the 1930s and upgraded in the 1960s to 115 kV – the last upgrade to the electric transmission system was sufficient to meet the power needs of Eastside communities for the last 50+ years.

PSE studied a variety of alternatives such as reducing demand through continued conservation, increasing the capacity of PSE’s existing electric transmission lines, generating energy locally, and building new infrastructure.

• Using batteries instead of building a new substation was considered, but the technology has not been used for the type and scale of problem facing the Eastside. Despite the progress made by the energy storage industry in recent years, an updated analysis concluded that battery storage is still not a practical solution to meet the Eastside transmission system capacity deficiency.
• PSE also looked at “time-of-use rates” and other incentive programs to reduce the demand. Time-of-use rates, which entail charging customers more to use energy during higher-energy use times, have also been tested by PSE on the Eastside; however, these programs were largely unpopular with customers.
• Solar power and other distributed generation efforts were also investigated as a possible solution. However, solar panels don’t generate electricity during the peak hours of electricity use, which occurs on winter mornings and evenings, and can be very expensive. Additionally, some homes cannot support the weight of solar panels or do not have the correct orientation.
• Other generation efforts explored would require building a 300 MW power plant and new transmission lines on the Eastside. During the solutions analysis process, PSE did look at building a natural gas-fired power plant in the Eastside area, but unfortunately, it either would not be permittable due to atmospheric emission and noise incompatibility, or it did not solve the identified capacity problem. New transmission lines would still need to be built to connect the power plant to the rest of the system.

The Environmental Impact Statement (EIS) process studied project alternatives in both Phase 1 and Phase 2. For more information about alternatives studied in the EIS, visit EnergizeEastsideEIS.org.

Industry experts and PSE have studied whether the Eastside’s electrical needs could be addressed by using batteries to store energy. Despite the progress made by the energy storage industry in recent years, an updated analysis concluded that battery storage is still not a practical solution to meet the Eastside transmission system capacity deficiency. 

An Eastside battery project would:

• Be significantly more expensive than PSE's plan to upgrade transmission lines along the existing corridor. Battery storage would cost approximately $825 million for a short-term solution and $1.4 billion for the complete solution, compared to an estimated $150 million to $300 million for Energize Eastside.
• Require a huge battery farm on a scale that has never been built. To meet Eastside demand, a battery project would be up to 43 times larger than the world’s largest operational project (Tesla’s Hornsdale project in South Australia). 
• Exceed the supply of energy storage systems. The commercial and supply-chain viability of an energy storage system for the Eastside area is unclear as it would exceed total U.S. energy storage deployments in 2017 by approximately 6-13 times. 

Battery storage was studied and analyzed in:

• Strategen's Eastside System Energy Storage Alternatives Assessment Report Update, September 2018
• Quanta and PSE's Supplemental Solutions Report in Section 4.3
• Strategen's Eastside System Energy Storage Alternatives Screen Study, 2015
• The Cities' Phase 1 and Phase 2 Environmental Impact Statements under Alternative 2

While battery storage isn’t a practical option for the Eastside’s needs, PSE is exploring the viability of the technology on a small scale.

While it is technically feasible, in Washington state it is up to the community to decide whether to make that investment. Overhead transmission lines are PSE's first option for their combination of reliability and affordability – both of which are important to our customers. While undergrounding is an available option, the biggest challenge to underground transmission lines is cost. For more in-depth information about underground transmission lines, read our fact sheet.

The construction costs for an overhead transmission line are about $3 million to $4 million per mile, versus $20 million to $28 million per mile to construct the line underground. When a new line is constructed overhead, project costs are distributed evenly between PSE’s 1.1 million customers and paid for over time. If a transmission line were to be constructed underground, PSE can’t justify asking customers across its entire service territory to pay the significant cost increases.

That’s why, per state-approved tariff rules, the requesting party, often the local jurisdiction, must ultimately decide whether to make this investment. The requesting party would then be responsible for paying the difference between overhead and underground costs. For Energize Eastside, in addition to the significant siting challenges, no local jurisdiction has agreed to invest in undergrounding.

In addition to cost, there are other factors to consider such as environmental and neighborhood impacts.

• Underground transmission lines require an easement 30 feet to 50 feet wide, which, unlike with overhead lines, must be completely free of trees.
• Underground transmission lines require large (20 feet x 30 feet) access vaults every quarter mile which can be very disruptive to adjacent neighborhoods and the environment.
• Repairs take much longer and can be more difficult with underground lines. While overhead lines can be repaired within hours or days, underground transmission line repairs can take days or even weeks.

Electric and magnetic fields, or EMF, are found wherever there is electricity – in household wiring, electrical appliances, computers or power lines. Over the past 45 years, there have been many scientific studies conducted to determine if EMF has any effect on human health. To date, the scientific community has concluded that current evidence does not support the existence of any health consequences from exposure to EMF.

• The Environmental Impact Statement (EIS) process also studied EMF and concluded that no adverse impacts from magnetic fields are expected. Specifically, “the magnetic field levels associated with the project are anticipated to be lower than existing field levels along the existing transmission line corridor.”

For more information about EMF in the Phase 2 Draft EIS, visit EnergizeEastsideEIS.org.

At PSE, safety is always our top priority and we are committed to keeping our customers informed. We understand that local residents may still wish to learn more. PSE has hired Drew Thatcher – an independent, board-certified health physicist – to address more specific EMF questions. If you or your neighbors would like to ask questions of Drew, the Energize Eastside team would be happy to connect you with him for more information. Read more about EMF in the detailed findings from the Electric and Magnetic Field (EMF) investigation for the Energize Eastside project route options.

For more details about EMF studies, exposure limits and PSE’s approach to EMF, visit pse.com/pages/electromagnetic-fields.

Regular upgrades or additions to the electric infrastructure are shared by all of PSE’s 1.1 million customers and paid for over time. We don’t yet know the total cost of the project, but the current estimate is around $250 million. Customers will not see any changes in their monthly bill to pay for this project.

PSE will upgrade the existing four wooden poles with one or two steel poles. New poles will be located in similar locations as the existing poles. The existing poles typically range in height from 55 feet to 65 feet, and the new poles will either be a single pole typically at 80 feet to 100 feet in height or two poles typically at 70 feet to 85 feet. In some locations, poles may need to be taller than 100 feet, such as when crossing a highway. The line height for the lowest of the upgraded 230 kilovolt (kV) transmission lines will be similar to current heights. For most new poles, additional lines will be stacked vertically above this first line.

View our Photo Simulations to see conceptual photos of the upgraded transmission lines.

According to federal standards, PSE is required to maintain safe clearances between vegetation and our lines. With the upgraded transmission lines, we will have to comply with PSE’s 230 kV vegetation management standards.

All trees directly under the lines and in the wire zone with a mature height of more than 15 feet must be removed. Outside of that zone, but within the right of way, we may need to selectively trim and/or remove trees to protect the transmission line.

However, PSE's Vegetation Management team ultimately decides which trees can stay or be removed. They will work with each property owner to develop a vegetation strategy for the property, which could include preserving specific trees and determining replacement options for trees that require removal.

For more information, visit PSE’s tree trimming and maintenance information center.

No. To solve the Eastside’s transmission capacity deficiency, we have to build the project in its entirety.

For instance, if we only built the south half, then the Sammamish substation in Redmond would still be at risk of overloads. This doesn’t meet our federal reliability requirements and puts our Eastside customers at risk of outages.

PSE does not anticipate needing to acquire property or access to and use of private property via easements. When use of private property is required, PSE negotiates fair market value purchase of easements with the affected property owner.

Should PSE need to study properties or conduct fieldwork, we will work directly with property owners and tenants to access those properties. PSE will notify all property owners and tenants before crews access their properties.

Substations are critical links in the electric system, containing utility circuit protection, voltage regulation, and transformers that step down higher voltage to lower voltage. Before reaching homes and businesses, power is routed through our transmission system to a substation where transformers change the power to a lower voltage that can be utilized by customers.

In general, 230 kV transmission lines do not produce noise like that of higher voltages. This is because over the years, transmission line design improvements have contributed to minimizing audible noise levels.

Audible noise from 230 kV transmission lines is generally less than 40 dBA but can be as high as about 50 dBA. To put these sound levels into perspective, 40 dBA is the sound of a whisper while a 50 dBA noise would be the background noise in an office. In the rare instance where noise above this standard level can be heard from a 230 kV line, a simple adjustment to a piece of equipment on the line can usually solve the problem.

An evaluation of audible noise will be conducted as a part of the overall design of the transmission line.

Interstate pipelines, whether they transport natural gas or liquid petroleum products, are held to both state and federal safety regulations administered by the:

• Federal Energy Regulatory Commission
• US Department of Transportation’s Pipeline and Hazardous Materials Safety Administration
• Washington State Department of Transportation
• Washington Utilities and Transportation Commission