Least-Conflict Solar Siting

Exploring pathways to protect Washington’s unique and diverse habitat and agricultural lands while producing the solar energy needed to help the state’s utilities reach 100% clean electricity.

The Least-Conflict Solar Siting project concluded at the end of June 2023 with the publication of the Least-Conflict Solar Siting on the Columbia Plateau report.

The mapping tool and maps continue to be accessible through the Least-Conflict Solar Siting Gateway.

You are still welcome to join the Email list. However, it will only be used for news about data and map updates, announcements for mapping tool trainings if available, or news about other WSU Energy Program siting projects such as the upcoming Pumped Storage Hydropower Siting project.

The Least-Conflict Solar Siting Project poses the question: Where can utility-scale solar be developed in the Columbia Plateau region while also ensuring that important natural habitat, productive farmlands and ranchlands, and tribal rights and cultural resources are protected?

To do this, the Washington State University Energy Program is leading a voluntary, collaborative, non-regulatory effort that engages relevant stakeholders, Tribes, and key agencies in a conversation and process to identify least-conflict areas for utility-scale solar development. The intent is to reduce land use conflicts and minimize negative impacts to natural and working lands while increasing solar renewable energy production. The project will make relevant spatial data available to the public, create maps highlighting the least-conflict areas in the region, and produce a final report by June 30, 2023.


The Clean Energy Transformation Act requires Washington state utilities to meet 100% of their load with clean, renewable sources of energy by mid-century. To help meet these requirements, utility-scale solar developments are necessary. A large increase in proposals for solar development in the Columbia Plateau region of eastern Washington is putting pressure on communities and local governments, and risking loss of some of the region’s productive farmland, ranchlands, and native shrubsteppe habitat—over half of which has already been lost.

To address this situation and find a common path forward, a bipartisan group of stakeholders and legislators secured state funding for the Least-Conflict Solar Siting Project in the 2021 Washington state legislative session. Funding is appropriated through a budget proviso for fiscal year 2023.

How the Least-Conflict Process Works

Groups of participants with interests in farmland, ranchland, and environmental conservation, etc., are guided through an exercise to map lands that are of high value from each group’s perspective. Lands that would generate less opposition to solar developments – the least-conflict lands – will be identified and mapped. A solar industry group identifies the best opportunities for their industry.

Tribal involvement is specific to each Tribe, and may include feedback of the draft maps and additional mapping layers.

An overlay of the maps identifies the common least-conflict lands. Maps and data are stored in an online platform for public use during the project and after it concludes. An important outcome of this project is for the data and maps to be used by planners, agencies, solar industry, Tribes, stakeholders, and others.

All interested persons are invited to three large meetings—which occur throughout the process—to stay informed, offer feedback, and provide input on other related issues. All of these meetings are likely to be virtual due to ongoing COVID-19 precautions. 

Stay Informed

Register here to join our email list for announcements and news.


Karen Janowitz