Assiniboine and Sioux Tribes of the Fort Peck Indian Reservation - 1994 Project

Project Overview
Tribe/Awardee: Assiniboine and Sioux Tribes of the Fort Peck Indian Reservation
Location: Poplar, MT
Project Title: Feasibility Study for Wind Energy Project at the Fort Peck Tribes Reservation
Type of Application: Feasibility
DOE Grant Number: DE-FG48-94R810527
Project Amounts:
DOE: $249,476
Awardee: $0
Total: $249,476
Project Status: Complete  More
Project Period
of Performance:
Start: September 1994
End: September 1997

Project Description


The Fort Peck Assiniboine and Sioux tribes in northeastern Montana are conducting a wind resource assessment at five sites on their reservation, in conjunction with the Bechtel Corp. Preliminary data collected in mid-1995 showed average wind speeds between 16.3 and 16.8 mph at four of the sites. The Western Area Power Administration (WAPA) performed a transmission study that indicated that additional transmission capacity would need to be constructed to carry the output of a commercial-scale wind farm.

The use of wind energy is technically feasible at present and it is becoming economically competitive in many locations around the globe. More than 5,000 mW of wind turbine capacity has been installed in the world, with 1,750 mW installed in the United States as of 1995. The National Renewable Energy Laboratory (NREL) has indicated that the Fort Peck Reservation in northeastern Montana could be a suitable site for the development of wind energy. Other entities, such as the Montana Power Company and the Electric Power Research Institute (EPRI), have also indicated that Montana has a good wind resource potential. The Fort Peck Tribes have a goal of becoming energy self-sufficient and potentially an important energy supplier for their region. They further have a vision of developing their land and resources in an environmentally sound manner. This led to the Council of Energy Resource Tribes (CERT) conducting a preliminary wind energy analysis for the Fort Peck Tribes in 1985 that concluded that there is a sustained wind energy resource on the reservation and that a wind power plant would be feasible under a proper financial structure.

The Fort Peck Tribes Reservation is located in northeastern Montana and has approximately 2 million acres of land. The region is classified as semi-arid and is part of the Northern Great Plains region. Typical topography consists of rolling plains slightly etched by the Missouri and Poplar Rivers and their tributaries. Land ownership is divided into tribal lands (16%), land allotted to tribal members (32%), and fee or private ownership (52%). The Fort Peck Tribes are in the process of re-acquiring their land. The majority of the land is not under tribal ownership. The towns of Poplar, Wolf Point, Frazer, and Brockton all lay within the reservation boundaries. Past studies have indicated that the wind regime on the reservation was at least a Department of Energy (DOE) class four. Wind class ratings range between one and seven with seven being the highest. A wind class rating of four has average wind speeds of 5.5 to 6.0 m/s at 10 meters above ground level.

The background photo shows the Assiniboine and Sioux Industries building, where manufacturing is carried out. Superimposed photos show a large metal stamping machine inside the building; an anemometer on the Fort Peck reservation used to measure the wind speed; and the entrance to the Fort Peck Indian Reservation Tribal Office.

The Fort Peck Assiniboine and Sioux tribes conducted a wind resource assessment at five sites on their reservation, in cooperation with the Bechtel Corporation. Measurements showed that the wind speeds range between classes 5 and 6, which would make wind generation commercially viable.


The objective of the feasibility study documented in this report is to assess the technical and economic feasibility of a staged-development, utility-grid-interactive, multi-megawatt wind power plant at the Fort Peck Reservation. The Fort Peck Tribes contracted with Bechtel Corporation to conduct the primary engineering assessment and Ron Nierenberg, consulting meteorologist, to coordinate the meteorological analysis. The study was designed to assess the technical viability of a wind power project based on wind regimes, land status, and electrical interconnection and transmission. Activities in this study entailed collecting wind data at five sites, assessing the transmission and distribution characteristics of the surrounding grid, conducting an initial environmental impact assessment, creating a conceptual design for the power plant(s), and conducting an economic analysis. The power plant design is based on the wind resource, land availability, and transmission capacity for a large-scale plant or for energy self-sufficiency.

Early in the process of the wind feasibility study, two town meetings were held in Poplar, Mont., to inform and engage the local community members in the wind feasibility study. During the presentation, the study process and goals were outlined and potential follow-on development scenarios were discussed. To the extent possible, the presenters showed the visual impacts of modern wind farms using slides and other visual materials. In particular, the presentation highlighted that lands having wind plants are compatible with other uses including farming, bison ranges, and cattle ranching. Concerns expressed by those attending the town meeting included: the reduction of prime hunting ground; avian impacts; and integration of a wind power plant in a restructured utility industry.

Project Actions and Resultant Data

This report documents a study by the Fort Peck Tribes of the feasibility of installing a wind energy power plant on their reservation in northeast Montana. The study was funded by a DOE Title XXVI grant and prepared with the assistance of Bechtel Corporation. Two wind power plant options were considered: I) a large-scale wind power plant for electricity sales to the regional grid; and, 2) a smaller wind power installation solely for the use of the Fort Peck Tribes. The feasibility study included: 1) assessment of the wind resource on the Fort Peck Tribes Reservation, 2) evaluation of the ability of the existing transmission system to evacuate power generated on the reservation, 3) development of engineering conceptual designs and cost estimates for the wind energy plants, 4) identification of relevant environmental issues, 5) determination of the cost of electricity to be generated; and, 6) review of the market to purchase energy from the wind power project.

Assessment of the Wind Resource

Twelve months of wind data were collected at five sites: Cameron Point, Cameron Ridge, Wall Ridge, Scout Mesa, and Poplar Bluff. The data indicate that the wind resource has average wind speeds that fall within the DOE classes 5 and 6. Winds in class 5 correlate to wind speeds between 7.5 and 8.0 m/s at 50 meters above ground level and winds in class 6 have average wind speeds ranging from 8.0 to 8.8 m/s at the same height. The wind resource on the reservation also has a very low turbulence intensity, indicating that there would not be undue stress on the wind turbines (which could shorten wind turbine life). Thus, the wind resource at the Fort Peck Tribes Reservation appears to be suitable for a large-scale wind power plant.

Transmission System Evaluation

WAPA conducted an initial capacity analysis and determined that transmission capacity limits are 45 mW at the Cameron Point site and 25 mW at the Wall Ridge site. A large-scale wind power plant could be developed in two phases. Phase I would be designed within the constraints of the local transmission line capacity limits. Phase II would be accompanied by transmission upgrades. WAPA has planned several transmission improvements that would eliminate some of the present transmission capacity constraints. If Phase I is built at Cameron Point, Phase II could be built at Cameron Ridge for a 160 mW expansion. The total capacity at the Cameron area would be 200 mW.

Power Plant Design

The conceptual design includes road access, foundations, in-plant electric distribution systems, and connection to the main transmission grid. The Cameron Point, Cameron Ridge, and Wall Ridge sites were chosen for more careful analysis because of their superior wind regimes and the transmission capacity availability in the near vicinity. All three sites provide flat locations at high elevations, making them ideal for wind power plants. Also, at the Cameron area, the turbines could be installed primarily on tribal lands.

Wall Ridge provides the strongest wind energy regime based on the wind data collected during this study. At this location, 50 600 kW wind turbines could be installed. Wall Ridge provides an alternative location to the Cameron Point and Cameron Ridge sites.

Environmental Issues

During the study, no environmental issues were identified that would prevent a wind power plant installation. No endangered species have been seen in the vicinity of the potential areas. Land use around the potential sites is principally for grazing, recreational purposes, and some farming. Grazing, recreational activities, and wind power plants are compatible activities. In some parts of the world wind turbines and farming are also compatible. A detailed environmental impact statement would be required if the plant is built, in particular for road construction and transmission interconnections. Because the sites are located far from population centers, there are no foreseen visual or noise impact issues to address.

Project Costs

The engineering, procurement, and construction (EPC) costs have been estimated for the potential plants. The EPC costs for Cameron Point and Wall Ridge are slightly more than $1,000 per kilowatt installed and Phase II, Cameron Ridge, is approximately $950/kW installed. The Phase II Cameron Ridge plant would benefit from projected improvements in wind turbine manufacturing and economies of scale. The wind turbines constitute more than 70% of the plant costs.

Cost of Electricity

The economic viability of the wind power plants was assessed. The ownership scenarios analyzed included 100% tribal ownership and 100% private ownership. With a tribally owned project, tax-free bonds with a low interest rate could be used. However, a Native American-owned plant does not qualify for the production tax credits and only a limited amount of the electricity generated may be sold for private use. Based on estimated project costs and tax-free bond financing, the levelized electricity rates for a Phase I project at Cameron Point or Wall Ridge are 5.5 and 5.4 cents/kWh, respectively. A privately owned wind power plant on the Fort Peck Tribes Reservation is estimated to be able to produce electricity for less than 5.4 cents/kWh. If a Phase II expansion were conducted at Cameron Ridge, the electricity costs are estimated to be less than 4.4 cents/kWh.

Estimated Energy Costs in $/kWh
Ownership Private 1st year Private LEC Tribal Ownership 1st year Tribal LEC
Cameron Point .045 .0557 .057 .0554
Cameron Ridge .039 .481 .054 .0525
Wall Ridge .0465 .0575 .056 .0542

LEC = Levelized Electricity Cost

Power markets potential markets for the wind power include:

  • WAPA,
  • customers who desire green power,
  • local electric cooperatives; or,
  • the Fort Peck Tribes.

Since deregulation of wholesale power in the United States has been initiated, wholesale electricity rates have decreased to 2 cents/kWh and less in the region, and Montana currently has excess capacity. While some utilities are aggressively pursuing green power, utilities and cooperatives in Montana are not interested in purchasing electricity that will cause their customers' electricity rates to increase, regardless of the energy source. Green power markets exist outside of Montana, however a specific customer has not yet been identified.

The annual electricity consumed by some of the major demand centers associated with the Fort Peck Tribes was assessed and found to be approximately 2.5 gWh. Two 600 kW wind turbines could be installed to meet this demand. The Wall Ridge and Scout Mesa sites were chosen as the potential self generation locations because of their accessibility and proximity to the main grid. The electricity would be included in the overall utility or cooperative mix and credited to the participating tribal centers on their electricity bills. Based on the EPC cost estimates and low interest rate financing, the levelized energy costs (LEC) produced at the sites is estimated to be 7.8 and 10.1 cents/kWh for Wall Ridge and Scout Mesa, respectively. If a grant or other financial assistance were available, such that the project would cost less than $1 million installed at Wall Ridge, the LEC would be approximately 5.4 cents/kWh. The Fort Peck Tribes pay between 3.5 and 7.2 cents/kWh with most of the electricity being purchased at approximately 4.2 cents/kWh. On a strict economic basis, it would not be recommended that the Fort Peck Tribes pursue a small-scale wind power generation system at this time.

Results, Conclusions, Findings, and Recommendations

The Fort Peck Tribes have a very good wind energy resource and location for a large-scale wind power plant. However, Montana has a surplus of electric energy and the wholesale and retail energy sold in the region is less costly than that which could be produced by the wind power plants. The analysis for a small wind generation system for the tribe's sole use also does not appear to be competitive on a strict economic cost basis.

The green power market is beginning to develop, particularly in the coastal states of the United States. This market could be a very promising opportunity for the Fort Peck Tribes in one to two years.

It is recommended that the Fort Peck Tribes continue to gather wind data and follow the green power market during the next few years. A student at the Fort Peck Community College received funding from the DOE to continue with the wind data collection and analysis process. This report and the wind data form a starting point for a successful future wind power development project on the Fort Peck Tribes Reservation.

Project Status

For project status or additional information, contact the project contact.

Project Contact

Fort Peck Tribes
PO Box 1027
Poplar, MT 59225
Telephone: (406) 768-5155