There is broad agreement that a significant increase in the use of renewable energy is dependent on expansion of the existing transmission grid. The publication of the Western Renewable Energy Zones - Phase 1 report in June 2009 provided a view of where the richest, most commercially viable renewable resources are within the Western Interconnection. This was an important first step toward expanding renewable energy development. Since the publication of the report, WGA has turned its focus to some key next steps: determining which of the high-quality areas are of greatest interest to electric service providers, determining how their renewable resources can best be developed, and planning for a transmission network that will bring those resources to market.

In June 2009 the United States Department of Energy announced the availability of stimulus money to analyze transmission requirements under a broad range of alternative energy futures and to develop long-term, interconnection-wide transmission expansion plans. In December DOE announced a combined total of $26.5 million would be given to the WGA and the Western Electricity Coordinating Council to complete this work.  WGA and its affiliate, the Western Interstate Energy Board, are concentrating their efforts in two major areas: continuation of activities initiated under the WREZ project, and the development of alternative energy futures that can be modeled into transmission plans that will open up high-quality renewable resource areas.

An exciting element of the transmission planning process is that for the first time wildlife and water sensitivities will be incorporated into the modeling analyses. Part of the DOE funding will go to states for the development of wildlife decision support systems that can be used to help assess the viability of new energy generation and transmission in certain areas. There also will be funding devoted to examining the regional impacts of new energy generation on water use, including a look at the potential impacts of long-term drought on energy production. The wildlife and water information will form critical inputs to the transmission modeling, and will go a long way toward increasing the potential viability of any transmission plan.

Phase 1 Report

The WGA and the U.S. Department of Energy released a joint WREZ Phase 1 report on June 15, 2009 that takes the first steps toward identifying those areas in the Western Interconnection that have both the potential for large scale development of renewable resources and low environmental impacts.

In Phase 1 the WREZ initiative brought together diverse interests to develop information and analytical tools that will assist public utility commissions, energy and transmission developers, utilities and others working to bring more renewable energy online.

GIS layers used in Phase 1 can be viewed and downloaded by logging on to the the NREL WREZ GIS portal:

Username: wrez
Password: guest

The portal is data intensive, so be patient when drilling down on these maps.

During the first phase of the WREZ initiative, diverse interests were brought together to develop information and analytical tools that will assist public utility commissions, energy and transmission developers, utilities and others working to bring more renewable energy online.

Work Group Products

Environment & Lands Work Group

• Phase 1 Report
• Exclusion Areas and Initial Avoidance Areas – Summary List
• Exclusion Areas
• Initial Avoidance Areas
• Significant Areas of Consideration
• Western Governors’ Wildlife Council Wildlife Sensitivity Maps

Zone Identification and Technical Analysis

• MW and GWh potential in Resource Hubs
• Supply Curves for Resource Hubs
• Technical report on ZITA analysis and quantification of Resource Hubs