The Ivanpah Solar Electric Generating System is currently operational and continues to feed power into the grid. Despite significant public attention surrounding its original performance and environmental challenges, the facility remains a functioning, large-scale example of renewable energy technology in the United States. Its continued operation confirms its role in the nation’s effort to transition toward cleaner power sources. The history of the project, including its groundbreaking technology and the difficulties encountered, has contributed to persistent public questions about its viability.
Defining the Ivanpah Solar Electric Generating System
The Ivanpah Solar Electric Generating System (ISEGS) is a Concentrating Solar Power (CSP) facility situated in the Mojave Desert, near the California-Nevada border. This complex is spread across approximately 3,500 acres of federal land and consists of three individual power plants with a combined gross capacity of 392 megawatts (MW). The project, which began commercial operation in early 2014, was one of the largest solar thermal power stations in the world at the time of its commissioning.
The plant utilizes a unique power tower design, which contrasts with common photovoltaic solar panels. This system employs over 173,500 dual-mirror devices called heliostats, which are precisely controlled by software. These mirrors track the sun and focus its energy onto water-filled boilers positioned atop three individual towers, each standing 459 feet tall. The concentrated sunlight superheats the water to create high-temperature steam that drives conventional steam turbines to generate electricity.
Current Operational Status and Power Generation
The Ivanpah facility is currently managed by a joint ownership group that includes NRG Energy, BrightSource Energy, and Google, and it continues to generate electricity for California utilities. The plant has a nominal net capacity of 377 MW, and its ongoing production contributes significantly to the state’s renewable energy portfolio. Recent performance data indicates that operational adjustments have brought the plant closer to its projected generation goals.
Despite initial reports of underperformance, the plant has shown improvement over time, reaching nearly 91.1% of its original production target by its seventh year of operation. A long-standing challenge involves the necessary use of natural gas-fired boilers, which help the plant reach operating temperature during morning start-up and maintain steam during transient cloudy conditions. While this auxiliary fuel use has been controversial, it is an operational measure that allows the thermal power plant to deliver consistent, dispatchable electricity.
The plant’s future remains secured following a recent regulatory decision. In 2025, the owners finalized an agreement to terminate two of the facility’s three power purchase agreements with Pacific Gas and Electric Company (PG&E), which would have led to the decommissioning of those two units starting in 2026. However, the California Public Utilities Commission (CPUC) rejected this termination. The CPUC cited the need for reliability and adherence to the state’s clean energy mandates as reasons to keep the plant fully operational. This regulatory reversal ensures that all three units will continue to operate, highlighting the state’s continued reliance on the facility’s output.
Historical Context of Performance and Environmental Concerns
The public skepticism surrounding Ivanpah’s long-term viability stems from two major issues that arose in the first few years of its operation. One significant challenge was the considerable gap between its projected and actual power output, particularly in its initial years. For instance, the facility’s actual capacity factor for 2018 was reported as 24.1%, falling below the original planned figure of 28.5%.
This underperformance was linked to the inherent difficulties of balancing the complex thermal system. The need to increase the allowable annual fuel usage limit for the auxiliary boilers was one of the first public indicators that the plant was struggling to meet its power output using solar energy alone. This reliance on non-renewable fuel sources contradicted the project’s initial pure-solar image, fueling public debate.
The other major controversy centered on avian mortality, an issue that generated widespread negative publicity. Birds flying through the concentrated solar flux, the intense heat created by the thousands of mirrors, were often singed or killed, a phenomenon workers referred to as “streamers.” Early estimates suggested that as many as 3,500 birds may have been killed in the plant’s first year of operation. The cause of death was determined to be either collision with the facility’s structures or singeing from the high solar irradiance. To mitigate this impact, the facility implemented specific operational changes, such as adjusting the aiming strategies of the heliostats during standby. These changes were designed to spread the concentrated light and reduce the lethal heat zones, minimizing the plant’s environmental effect on the desert’s wildlife.