Renewable energy technologies generate electricity, fuels, or heat through the use of resources that are continually replenished, such as wind and sunlight. Electricity generation using wind or solar technology can range from small-scale production—for example, rooftop solar panels on a home—to utility-scale production of hundreds of megawatts of Development of electricity, enough to power tens of thousands of homes.utility-scale renewable energy projects on federal land occurs primarily on lands managed by BLM. Several utility-scale wind projects have been operating on BLM-managed lands since the early 1980s, primarily in California. In May 2012, the first utility-scale solar power plant began operating on BLM-managed land. Currently, about 1 percent of the nation’s electricity generated from wind and solar energy comes from resources on federal lands. Figure 1 shows the federal lands managed by BLM. The most common technologies for utility-scale wind and solar development include the following: Wind energy. Wind farms consist of a number of turbines built close together to produce utility-scale wind power. Horizontal-axis turbines, the most common, constitute nearly all utility-scale wind turbines in the United States. (See fig. 2.) To generate electricity, horizontal-axis turbines capture the wind’s energy with two or three propeller-like blades mounted on a rotor sitting atop a tower. A smaller utility-scale wind farm may have 6 turbines on 100 acres and generate about 3 megawatts, and a larger wind farm may have more than 100 turbines on about 10,000 acres, and generate approximately 300 megawatts. Solar energy. Multiple technologies exist for utility-scale solar power, such as photovoltaic and concentrating solar power technologies. Solar photovoltaic technologies convert energy from sunlight directly into electricity, using arrays of solar panels. (See fig. 3.) Concentrating solar technologies use two types of mirrors with tracking systems, either curved (parabolic) or flat, to focus the sun’s energy onto a small area. The concentrated light is then used to heat water or other fluids that create the steam to power a conventional turbine generator and produce electricity. Examples of concentrating solar power technologies include parabolic trough and power tower. Parabolic trough technology collects energy from the sun using parabolic mirrors that concentrate heat onto solar thermal equipment, often a tube filled with fluid that runs the length of the trough at its focal point; the heated transfer fluid then powers solar steam turbine generators. (See fig. 4.) A power tower system consists of an array of dual-axis tracking mirrors that concentrate sunlight on a central receiver atop a tower. The working fluid in the receiver is heated to 500-800 ºC and then used as a heat source for a power generation or energy storage system. (See fig. 5.) An average solar plant, whether photovoltaic or concentrating, requires about 3 to 8 acres for every megawatt of generating capacity. For example, a small utility-scale solar plant occupying about 600 acres may generate 50 megawatts, and a large facility occupying about 4,000 acres may generate 550 megawatts. However it is generated, electricity from utility-scale wind and solar energy development is sold to utilities and conveyed to consumers through transmission lines, the same as electricity generated by more conventional sources such as coal- or gas-fired power plants. Developing wind and solar energy projects on a scale large enough to generate substantial electric power can affect the environment in both the immediate vicinity and across hundreds, or even thousands, of acres of land depending on the energy source. For example, the turning rotors of a wind turbine may injure or kill birds and bats, and wind farms may fragment wildlife habitat and plant communities. In addition, solar installations can affect habitat needed by various species, including those listed as threatened or endangered under the Endangered Species Act, such as the desert tortoise. Also, the water used in some solar technologies may diminish scarce groundwater in the arid Southwest. Wind and solar projects on BLM land are subject to federal laws and regulations as well as BLM policy. The Federal Land Policy and Management Act of 1976 authorizes BLM to issue rights-of-way on federal lands for a variety of purposes, including systems for generating, transmitting, and distributing electric energy. For purposes of this report, a right-of-way is an authorization to a qualified individual, business, or government entity to use a specific area of federal land for a specific amount of time for a certain purpose and with specific terms, conditions, and stipulations that, among other things, are intended to protect the environment, federal property and economic interests, and the public interest. Right-of-way holders are required to restore, revegetate, and stabilize the land disturbed by wind and solar projects within a reasonable time, to a condition satisfactory to BLM, as approved by BLM in their Plan of Development. For projects that may have a significant impact on the environment, the act requires applicants to submit a plan of construction, operation, and rehabilitation for the right-of-way that complies with applicable laws and regulations and the agency’s stipulations. By accepting the right-of-way, the holder agrees to comply with all terms, conditions, and stipulations of the right-of-way. Federal regulations authorize BLM to require a right-of-way holder to provide a bond to secure the obligations imposed by the right-of-way. According to BLM policy, a bond is required for each wind and solar facility on federal land. BLM may require an increase or decrease in the value of an existing bond at any time during the term of the right-of-way, according to federal regulations. BLM manages and oversees wind and solar projects as well as its other programs primarily through its headquarters, 12 state offices, 44 district offices, and 119 field offices. BLM’s National Renewable Energy Coordination Office oversees wind and solar development on federal land. The office also develops renewable energy policies and legislation, among other things. Realty specialists—located at the state, district, and field office level—administer the wind and solar rights-of-way, among other things. BLM’s process for authorizing a right-of-way begins with pre-application meetings between BLM and the prospective right-of-way applicant. Subsequently, the prospective applicant completes an application that includes a statement of technical and financial capability and a project description, and, for solar projects, a decommissioning and site reclamation plan. including associated environmental reviews under the National Environmental Policy Act. Once BLM approves the application, BLM authorizes the right-of-way. However, before the holder of the right-of- way can begin construction and land disturbance activities, BLM establishes the required bond amount—known as a bond determination— and notifies the right-of-way holder. Once the right-of-way holder obtains a bond and BLM determines that the bond is acceptable, BLM issues a notice to proceed. A decommissioning and site reclamation plan defines the reclamation, revegetation, restoration, and soil stabilization requirements for the project area. Wind site-specific testing. A site-specific right-of-way for individual meteorological towers and instrumentation facilities with a term that is limited to 3 years. Wind project area testing. A project area right-of-way for a larger site testing and monitoring area, with a term of 3 years that may be renewed. Wind energy development. A right-of-way to develop wind energy facilities generally for a term of 30 years that may be renewed. Facilities include wind turbines, as well as on-site access roads, electrical and distribution facilities, and other support. Solar energy development. A right-of-way to develop solar energy facilities for a term not to exceed 30 years that may be renewed. BLM manages and oversees wind and solar projects in part by maintaining data on each project electronically in two data systems— LR2000 and the Bond and Surety System. LR2000 is BLM’s electronic case recordation system that is used to capture information on the agency’s land and mineral projects. In the case of wind and solar projects, BLM captures information such as the date the right-of-way was issued, acres authorized, project location, case status (e.g., authorized, expired, or closed), and the actions that have taken place. The system also contains bond information for wind and solar projects, including bond numbers, amounts, and bond actions, such as the date when a bond was filed, accepted, or returned. For wind projects, LR2000 contains the number of authorized turbines and towers. The Bond and Surety System contains bond information, such as the type and amount of bond, as well as actions taken, including the date when a bond was filed, accepted, or returned.LR2000 as well as information about bonds into the Bond and Surety System. BLM has different policies for the development of wind and solar energy on federal land, and each policy contains provisions related to bonding. The wind and solar bonding provisions differ in a number of ways, such as minimum bond amounts and acceptable bond instruments. However, the agency has issued a proposed rule that would, among other things, establish consistent requirements for the bonding of the two types of projects. In 2008, BLM issued a wind energy development policy that includes provisions for bonding wind energy projects on federal land.the policy established a minimum bond amount of $2,000 per meteorological tower for site-specific and project area testing rights-of- way and $10,000 per wind turbine for wind energy development rights-of- way.