24/7 Concentrating Solar Power Plant Gains Approval in Chile

Spanish sustainable energy multinational Abengoa on May 9 announced that the Chilean Environmental Service's Evaluation and Review Committee unanimously approved its concentrating solar power (CSP) and energy storage project. The project is planned for the country's northern Atacama Desert region, which has the highest levels of solar radiation in the world, and will produce 110 megawatts of energy.

Dubbed Cerro Dominador, Abengoa's CSP project is “groundbreaking” in more ways than one. In addition to being the largest CSP facility announced in South America to date, it will be “the first to serve as a baseload power plant” -- supplying electricity 24 hours a day, seven days a week -- thanks to a molten-salts energy storage system capable of storing the equivalent of some 18 hours worth of electricity production, Abengoa explains in a press release.

Coming amid ongoing technological advances, the integration of grid-scale energy storage capacity in CSP (also known as solar thermal power) plants is being touted as a potential “game-changer” for the technology despite concerns and controversy regarding its environmental impacts.

Concentrating solar power and the environment

Generating environmental concerns and controversy here in the U.S., the Ivanpah Solar Electric Generating Station was commissioned this past February in California's Mojave Desert 140 miles southwest of Las Vegas.

The massive $1.6 billion, 392-MW (gross)/377-MW (net) plant, developed by BrightSource Energy with financial backing from NRG and Google, was built on intact desert habitat. Construction was temporarily called to a halt in the spring of 2011 due to concerns about its impact on Mojave desert tortoises, which are classified as threatened by the International Union for Conservation of Nature (IUCN).

Counterbalancing the environmental impacts of CSP plants, their triple bottom line benefits are substantial. As Abengoa states in its press release:

“The Cerro Dominador project forms part of the Chilean Government’s national renewable energy development program, intended to provide Chile with a clean energy future, while also promoting economic development and reducing the country’s dependency on coal and natural gas.”

Abengoa expects designing, building and operating the Cerro Dominador CSP facility will create 700 direct jobs and require up to 2,000 workers overall. Fifty long-term employees will be required once commercial operation begins. “Similarly, the development, commissioning and operation of the plant will generate a high number of indirect jobs, as well as a network of services and new industrial investments that will develop the local market, promoting economic growth in the country,” Abengoa adds.

Emissions-free, CSP projects also go a long way when it comes to climate change mitigation. Able to generate enough energy to power more than 140,000 California homes, the solar electricity produced by Ivanpah is projected to avoid more than 400,000 tons of carbon dioxide (CO2) emissions per year. Though its generation capacity is less than a third of Ivanpah's, Abengoa estimates the CSP at Cerro Dominador will avoid some 643,000 tons of CO2 annually.

In addition to climate-warming carbon and greenhouse gas emissions, the amount of water being used to generate electricity and produce transportation fuels has become an increasingly pressing, and costly, issue in the U.S. and globally over the past decade.

CSP at the Water-Energy Nexus

Compared to fossil-fuel energy sources, particularly oil and gas extracted from shale deposits by “fracking,” wind and solar power generation make minimal use of, and have a minimal impact on, water resources. As they produce electricity using conventional steam generation, CSP systems do use more water than solar photovoltaic (PV) or wind power systems. The water in CSP systems is recycled and used over and over again in a closed-loop, however, which minimizes the water required in electricity generation.

CSP systems also make use of water for cooling. At Ivanpah, BrightSource is using a dry, air cooling system. That results in Ivanpah using 90 percent less water than a conventional wet-cooled CSP plant, according to BrightSource.

CSP and integrated grid-scale energy storage

Acknowledging concerns about the environmental impacts of CSP plants, Research & Markets believes they will be assuaged, or at least overcome, and that the net benefits utility-scale CSP plants afford as compared to conventional fossil-fuel power plants will win out.

Assessing the environmental impacts of Cerro Dominador, Chilean environmental experts “took into account issues such as use of the land, water, air, emissions, and waste, as well as any other aspect that could generate an environmental impact in the area where the plant will be constructed,” Abengoa highlights.

Integrating grid-scale energy storage into utility-scale CSP plants is a milestone for the technology and intermittent renewable energy systems more generally. Abengoa was the first company to build and commercially launch a CSP-molten-salt power plant in the U.S.

Last October, Abengoa commissioned the world's largest parabolic-trough-and-tower CSP facility. With a rated generation capacity of 280 MW, the Solana CSP plant uses molten salt to store the equivalent of six hours worth of the plant's electricity output.

As Research & Markets sees it:

“Concentrating Solar Power (CSP) solar energy is the most promising and sustainable renewable energy; rolling out CSP systems offers both performance and competitive energy prices. CSP Solar provides a crucial energy solution that is utility scale and works 24x7 in combination with back-up stationary fuel cells.”

Whether making use of molten salts or hydrogen fuel cells, the integration of grid-scale storage capacity in CSP plants is a game-changer, according to Research & Markets. “A step-change in system costs is being achieved, putting the industry on the cusp of a major growth spurt,” the market research company asserts.

Image credits: 1) Abengoa, 2) BrightSource Energy; 3) Tractebel Engineering