An introduction to solar thermal energy with Joseph Desmond

“Respect for the environment informs our approach, from the technology we develop to the stewardship we practice.”

Joseph Desmond is Senior Vice President of Marketing and Government Affairs for BrightSource Energy, a company founded in 2006. BrightSource Energy is a leader in solar thermal technology. By concentrating the sun’s energy, the company produces high-value steam for electric power, petroleum and process markets worldwide. We talked to Joseph Desmond about BrightSource Energy’s vision and aspiration to build a carbon-free future.

The Beam: At BrightSource Energy, you have developed a solar thermal energy system. Can you explain to us what it means and how it works?

Joseph Desmond: BrightSource Energy designs, develops and deploys solar thermal technology to produce high-value electricity and steam for power, petroleum and industrial-process markets worldwide. BrightSource combines breakthrough technology with world-class solar power plant design capabilities to generate clean energy reliably and responsibly. BrightSource’s solar thermal systems are designed to minimize impact on the environment and help customers reduce their dependence on fossil fuels.

Our solar thermal energy systems generate power the same was as traditional power plants — by creating high temperature steam to turn a turbine. However, instead of using fossil fuels to create the steam, BrightSource uses the sun.

At the heart of BrightSource’s proprietary solar thermal system is a state-of-the-art solar field design, optimization software and a control system that allow for the creation of high-temperature steam. Thousands of software-controlled mirrors track the sun in two dimensions and reflect the sunlight to a boiler that sits atop a tower. When the concentrated sunlight strikes the solar receiver, it heats water to create superheated steam. The steam is either piped from the boiler to a conventional steam turbine to produce electricity, where transmission lines will carry the power to homes and businesses, or the steam is used in industrial process applications such as thermal enhanced oil recovery (EOR).

By integrating conventional power block components, such as turbines, with our proprietary technology and state-of-the-art solar field design, electric power plants using our systems can deliver cost-competitive, reliable and clean power when needed most.

We can also integrate proven molten salt storage of hybridize with a fossil fuel, further increasing output and reliability, and significantly reducing energy costs.

What are the environmental advantages of BrightSource’s technology? Do you work with environmental groups to develop your power plants?

Respect for the environment informs our approach, from the technology we develop to the stewardship we practice. Our concentrating solar power (CSP) technology exists to produce clean energy, address climate change, improve air quality and reduce dependence on fossil fuels. Equally important is the all-encompassing environmental approach we take to each of our projects. BrightSource’s solar thermal energy systems are designed specifically to minimize their impact on native ecosystems:

• Our pylon-based heliostats avoid sensitive plant habitats and allow for building around the land’s natural contours, which requires less grading and the use of extensive concrete pads rather than other solar thermal technologies. For example, with our technology, we can place pylons directly in the ground, without concrete pads, which allows for vegetation to exist within the field below the mirrors. We can also build on up to a 5% grade, meaning that we do not have to grade the site to achieve perfectly flat land, unlike photovoltaic (PV) and parabolic trough technologies.
• We can use dry-cooling, despite its additional cost, to reduce water usage by more than 90% over competing technologies.
• Unlike trough technology, the power tower design does not require the use of oil or other synthetic chemicals to produce electricity.
• Our plants are more land efficient than competing solar technologies.

We work closely with a number of local and national environmental groups when planning and executing our solar thermal plants. Feedback from these groups is essential in designing and deploying a thoughtful utility-scale solar plant.

Some people say that renewable sources of energy are facing increasing pressure from natural gas, which is falling in price and replacing coal in many places. How does it impact your work at BrightSource Energy?

U.S. CSP [Concentrated Solar Power] deployment experienced a few years of intense growth, with government support such as the SunShot Initiative and DOE [Department of Energy] loan guarantee program helping to move the technology from demonstration to commercial scale. However, abundant cheap shale gas and the success of PV-based distributed generation solutions has reduced the focus on the technology in recent years.

But, as the penetration levels of renewables increase in the U.S., policymakers and utilities are showing a growing interest in technologies that can ensure long-term reliability without increasing emissions. CSP with thermal energy storage is therefore attracting increasing attention as a flexible resource to help address the supply variability introduced by rapidly expanding wind and PV production.

We therefore believe the U.S. market for CSP (plus thermal energy storage) will rebound in the near future as a result of:

• Growing requirements for flexible, reliable clean energy
• Implementation of the EPA’s Clean Power Plan, which will drive further retirements of fossil fleet and create opportunities for CSP, including hybridization
• Increase of California’s renewable portfolio standard to 50%
• Further reduction of a financing risk premiums via successful technology deployment in other countries.

The U.S. market will also be in a good position to take advantage of lower costs and better performance for CSP technology, having since been deployed in projects around the globe.

Outside of the U.S., flexible, dispatchable resources such as CSP (with thermal storage) will be needed in order for many countries to achieve their economic, energy and environmental goals while maintaining grid reliability. IT will also receive more attention from governments that recognize its potential for localization.

South Africa is a particularly exciting area across all renewable technologies. The country is implementing the largest renewable energy program on the African continent to diversify its energy mix, which has historically been dominated by coal.

China is also looking to develop CSP with storage to complement its existing commitment to wind and solar PV — the government recently increased its target CSP allocation from 3GW to 10GW by 2020. BrightSource’s partnership with Huanghe Hydropower and Shanghai Electric to develop the proposed Huanghe Qinghai Delingha Solar Thermal Power Project comprising six towers at 135 MW each and China’s first commercial-scale CSP project that also incorporates storage is representative of the types of projects intended to be developed to meet this goal.

Latin America, India and the Middle East and North Africa region also represent great opportunities for large renewable energy projects.

One of the big advantages of solar thermal technology over photovoltaic solar panels is storage: the ability to store the heat after the sun goes down. Do your various projects have storage?

As CSP is becoming better understood, utilities are starting to recognize the attributes that make it attractive, particularly as the intermittency of PV and wind at scale are becoming a larger issue. CSP combined with thermal energy storage transforms a variable resource into a flexible, dispatchable generator able to release energy when it is needed most, or provide continuous power for energy-intensive industries. This dispatchable power can improve reliability and reduce integration costs, while also supporting higher levels of other variable renewables. BrightSource is working with a number of utilities to design optimal solutions that meet specific load profiles.

CSP is also able to ride through changes in weather patterns much more smoothly due to thermal inertia, as well as providing voltage support. Further, it provides “solar steam,” which can be hybridized with existing or new gas or coal plants as a way to reduce carbon intensity or boost efficiency during certain times of the day. The “solar augmentation” of existing fossil fuel power plants can offer a lower risk and lower cost alternative to constructing stand-alone solar plants.

In addition to generation electricity, CSP technology is an enabler for a much larger value chain. Other applications include desalination, mining and other industrial processes that require constant pressure and steam temperature, such as enhanced oil recovery. The latter is an area where BrightSource is already applying its solar thermal technology. Additionally, as mentioned above, the Huanghe Qinghai Delingha Solar Thermal Power Project we are developing in China’s Qinghai province will feature thermal energy storage.

What does it take to realise carbon-free energy?

There are many forms of renewable support structures available and what is effective for one country may not be as effective for another. The choices depend on the policy objectives of the government and the type of investment behavior the government wishes to incentivize. Additionally, development costs for the same technology can vary geographically, including by permitting jurisdiction and by applicable labour rates.

Regardless of the support mechanism, however, it’s policy consistency and clarity that most effectively builds confidence and attracts capital.

What are the next challenges to come for BrightSource Energy?

BrightSource is focused on designing, developing and deploying its solar thermal technology to produce high-value electricity and steam for power, petroleum and industrial-process markets worldwide.

BrightSource’s technology is featured in the following facilities:

• Solar Development Energy Center (SEDC), BrightSource Energy’s 6 MW thermal solar demonstration facility in Rotem, Israel. Fully operational since 2008, the facility is used to test equipment, materials and procedures as well as construction and operating methods.
• Chevron/BrightSource Solar-to-Steam Demonstration Facility located in Coalinga, California. The 29 MW thermal solar-to-steam facility began operation in 2011 to support enhanced oil recovery efforts at Chevron’s oil field.
• Ivanpah Solar Electric Generating System, a 377 MW (net) solar thermal facility located in California’s Mojave Desert. The project began commercial operation in 2013, delivering power to PG&E and Southern California Edison.
• Ashalim Thermal Solar Power Station, a 121 MW facility to be located in Israel’s Negev desert. Construction has begun and the project is scheduled to be completed in early 2017.

In addition to these projects, BrightSource is working to develop the proposed Huanghe Qinghai Delingha Solar Thermal Power Project, located in China’s Qinghai province.

Interview by Anne-Sophie Garrigou