Q: What is renewable energy?

Solar energy is a renewable energy source. Renewable energy resources, such as wind, solar, geothermal and tidal, are constantly replenished and will never run out. In contrast, fossil fuels, such as coal, oil, and natural gas are nonrenewable, that is, they are limited in quantity and will become more difficult and expensive to recover.

Q: What brought Hualapai Valley Solar LLC to this location?

In general, Arizona has some of the highest insolation values (from INcoming SOLar radiATION, which is a measurement of solar radiation energy received on a given surface area in a given time) in the United States. In particular, the Project area receives between 6.5 and 7.0 kilowatt-hours/square-meter/day (see National Renewable Energy Laboratory on-line data at www.nrel.gov/csp/maps.html). The selected site is located on private property, is relatively flat, and has good access to major electric transmission lines, all of which are critical components for a utility-size solar power plant.

Q: Where is the facility located? Why was this site chosen?

The facility is located approximately 27 miles north of the City of Kingman, Arizona. The site is currently vacant in a rural area with few residences. It is far enough away from major residential areas to not adversely affect existing residents, while being close enough to employ the population base. The selected site is located on private property, is relatively flat, and has good access to major electric transmission lines, all of which are critical components for a utility-size solar power plant.

Q: How does the acreage needed for this type of plant compare with other power plants in the state?

In order to accommodate the solar field for harvesting the sun’s energy, CSP facilities require more acreage than traditional fossil-fueled or nuclear power plants. Hualapai Valley Solar went through an extensive process to identify the best possible location for the HVS Project. Ideal locations for CSP plants have generally flat land (preferably less than 1% slope), high insolation values, an abundance of sunny days, are located near an existing transmission system, and the land is available for purchase.

Q: How much water will be used?

The preliminary design for the project uses wet cooling technology. Depending on the specific water quality of the raw water, the project will use between 2000 and 3000 acre-feet in an average year. This is less than half of the amount of water already allocated to the land for its currently approved residential Area Plan by an ADWR Letter of Assured Water Supply.

Q: How does the plant work?

The Project will use Concentrating Solar Power (CSP) technology to capture heat generated by sunlight and turn that heat into electricity. This CSP works by using parabolic-trough collectors to concentrate the sun's energy using long, curved (U-shaped) mirrors. The mirrors are tilted toward the sun, focusing sunlight on a pipe that runs down the focus of the trough. This heats the heat transfer fluid (HTF), a synthetic oil, that is flowing through the pipe. Then, the hot HTF is used to boil water to create steam for use in a conventional steam generator to produce electricity. In addition, some of the hot HTF flows into a molten salts storage tank, which retains and stores heat. That heat can then be extracted from the molten salts to produce electricity during cloudy periods, or even after sunset or before sunrise.

Q: What is CSP? Is it different from photovoltaic (PV) technology?

A: Parabolic trough solar power systems, or CSP, are well suited for central, large-scale generation plants that connect to the electric transmission systems. CSP uses the heat from the sunlight to make energy; whereas, photovoltaic uses the light to make energy. In desert climates like the southwestern United States, parabolic trough technology offers the lowest cost solar electric option for large-scale power plants. Electricity from large-scale parabolic trough power plants is 50% to 75% cheaper than electricity from photovoltaic systems (NREL). In addition, CSP systems use thermal energy, which can be readily stored in thermal storage systems utilizing molten salts. PV systems use electrical energy, which is less cost-effective to store.

Q: What is heat transfer fluid?

Heat Transfer Fluid (HTF) is a dense liquid, usually a synthethic oil that can be heated to very high temperatures on a repeated basis without degrading. In order to heat the HTF, the solar troughs concentrate solar radiation onto a pipe containing the HTF. The heated HTF then flows through a pipe system to deliver the heat to a conventional steam generator.

Q: Will the mirrored troughs create reflections that could affect pilots or passersby?

No. In order to maximize the amount of power the plant can produce, the shape of the trough focuses the sunlight on a pipe in the center of the trough and does not reflect it skyward. When viewed from the sky, the troughs will appear as a pond or lake because the mirrored surface reflects the blue sky.

Q: Why is this so innovative? Don’t we have a lot of solar generated power already?

Other facilities have been built with this proven technology including the SEGS projects in California and Nevada Solar One near Boulder City, Nevada in the US. However, the HVS project will incorporate significant thermal storage to enable it to provide better ‘quality’ electricity to the grid.

Q: What kinds of emissions will the plant generate?

The primary emission from the plant will be steam. In addition, a minor source air permit will be obtained primarily for the particulate emissions from the cooling towers. The project will also burn small amounts of fuel for freeze protection, turbine maintenance during shutdowns, and supplemental generation during rare extended cloudy Summer periods. Calculations base on an NREL ([insert link to study]) indicates that the HVS project could translate to a yearly offset of:
  • • 37.5 tons of nitrogen oxide
  • • 22.5 tons of carbon monoxide
  • • 950,000 tons of carbon dioxide (equals the amount of carbon dioxide given off by 175,926 average cars in one year)

Q: How many jobs will it take to run the plant? What are the qualifications?

There will be approximately 100 permanent positions at the power plant ranging from technicians to engineers and managers.

Q: Who will build this facility?

HVS will contract with a large contractor to complete the final design for and construct the project, while retaining its consulting engineer, Fichtner Solar, to provide quality control and oversight.

Q: Where will the labor force come from?

During construction, the contractor will use some of its own personnel and will hire locally to fill as many positions as possible. The contractor will rely on sub-contractors for much of the work from earthmoving to electricians and engineers, and will hire these skills and services locally whenever possible. HVS expects that much of the labor force will be from the Kingman area, as well as nearby cities and towns

Q: How will the power get to customers?

Solar power generated by the HVS Project will enter the regional electrical transmission grid through an interconnection with the existing transmission lines north of the project.

Q: Who will use the power generated by the HVS Project?

Regardless of which utility purchases the power, once the electricity enters the grid, it will flow where it is needed the most, similar to water flowing to the lowest point.

Q: Can I choose this specific power type for use in my home?

Possibly. Most utility companies offer options to purchase renewable energy. You will need to contact your local utility provider.

Q: Will the installation of this plant increase my rates?

Utilities in Arizona are required to purchase a certain amount of the electricity that they sell from renewable energy sources. Many utilities conduct bidding processes to ensure that they purchase only the most cost-effective energy source for their customers. One of the benefits of the HVS Project, other than reduced pollution, is the fact that its fuel (sunlight) is free and the cost of energy will grow much slower over time than the cost of any fossil-based alternative.

Q: What can you tell me about Hualapai Valley Solar LLC?

HVS is a single-purpose company created to develop, construct, own, and operate the Hualapai Valley Solar power plant.