BrightSource Technology, Southern California Edison combine storage, power tower technology to reduce cost, increase capacity, reliability of solar energy during peak demand for three PPAs
November 28, 2011
– Coupling Storage with High-efficiency Power Tower Technology Provides Cost-Competitive, Reliable and Dispatchable Solar Power during California’s Peak Demand Periods; Reduces Costs to California Ratepayers
BrightSource Energy, Inc., a leading solar thermal technology company, today announced the addition of its SolarPLUSTM thermal energy storage capability to three of its power purchase agreements with Southern California Edison (SCE). The agreements illustrate the critical value of highly-efficient power tower solar thermal technology with storage in providing utility customers with cost-competitive, reliable and dispatchable clean power that meets peak demand.
By adding storage to its solar thermal power plants, BrightSource is able to further reduce the total cost of energy by increasing its capacity factor - how much power a plant produces over a year – extending the production of electricity into later parts of the day when it is most needed by utilities.
“With these agreements, we’re demonstrating that power tower technology is not only advancing the solar thermal industry, but that utility-scale solar generation can be both cost effective and reliable,” said John Woolard, President and CEO of BrightSource Energy. “We’re thrilled to offer Southern California Edison a solution that provides higher value for its customers, while supporting a more reliable and stable grid for all Californians.”
Recent studies1 by the National Renewable Energy Laboratory point to the high value of concentrating solar thermal power technologies with storage. This added value is a result of the resource’s unique capabilities including:
To mitigate these integration costs, energy regulators, utilities, grid operators and policymakers are focusing their attention on advancing deployment of energy storage technologies. California recently passed Assembly Bill 2514, landmark legislation designed to encourage the adoption of energy storage technologies.
"Energy storage improves the overall efficiency of our electric power system which will lower costs for consumers," said Assembly Member Nancy Skinner (D – Berkeley), author of the bill. "The Assembly's passage of AB 2514 is another step that advances California's clean energy economy and represents a great economic opportunity for the State."
A BrightSource power tower solar thermal system uses a field of software-controlled mirrors called heliostats to reflect the sun’s energy to a boiler atop a tower to produce high temperature and high pressure steam. The steam is used to turn a highly efficient steam turbine to produce electricity. When storage is added, the steam is directed to a heat exchanger, where molten salts are further heated to a higher temperature, thus efficiently storing the heat energy for future use. Later, when the energy in storage is needed, the heat stored in the molten salts is used to generate steam to run the turbine.
Under the original power purchase agreements with Southern California Edison, BrightSource would provide approximately four million megawatt-hours of electricity annually across seven power plants. Due to higher efficiencies and capacity factors associated with energy storage, the new set of agreements will provide approximately the same amount of energy annually but with one less plant, reducing the land impacts of delivering this energy and avoiding transactional costs that ultimately impact California’s ratepayers.
The new set of contracts, if approved by the California Public Utilities Commission, now consist of two BrightSource solar thermal plants scheduled to deliver electricity in 2015 and three BrightSource plants with energy storage scheduled to deliver electricity in 2016 and 2017. In addition, BrightSource and its partners – NRG Energy, Google and Bechtel - are currently constructing a 126 megawatt plant for Southern California Edison at the Ivanpah solar project in southeast California.
About BrightSource Energy, Inc.
BrightSource Energy, Inc. designs, develops and sells solar thermal power systems that deliver reliable clean energy to utilities and industrial companies.
1“The Value of Concentrating Solar Power and Thermal Energy Storage.” Ramteen Sioshanis and Paul Denholm. February 2010.