California solar influx causes negative wholesale rates

Facebook
Twitter
LinkedIn
Reddit
Email
From the hours of 11am to 2pm on 11 March, the total solar share of gross demand exceeded 50%, according to the EIA. Source: Flickr/ lindalino

On 11 March, for the first time ever, over 50% of California’s power needs were met with solar power, according to the US Energy Information Administration (EIA).

From the hours of 11am to 2pm, “the total solar share of gross demand probably exceeded 50%,” the EIA said – noting that it was a combination of residential and commercial rooftop generation that constituted 4 million kWh of electricity during peak time.

This article requires Premium SubscriptionBasic (FREE) Subscription

Unlock unlimited access for 12 whole months of distinctive global analysis

Photovoltaics International is now included.

Not ready to commit yet?
  • Regular insight and analysis of the industry’s biggest developments
  • In-depth interviews with the industry’s leading figures
  • Unlimited digital access to the PV Tech Power journal catalogue
  • Unlimited digital access to the Photovoltaics International journal catalogue
  • Access to more than 1,000 technical papers
  • Discounts on Solar Media’s portfolio of events, in-person and virtual

Or continue reading this article for free

During the same time window, wholesale electric rates dipped below zero, compared to the average price of between US$14-$45MWh in March between 2013 and 2015. This is because of a net market oversupply; as many forms of power generation cannot be easily shut down when solar generation peaks.

California has seen an almost 50% growth rate in the amount of utility-scale PV installed last year, contributing to the negative power prices. Indeed, the Golden State has almost half of all the solar power in the US. As of December 2016, California’s independent system operator CAISO reported 14GW of distributed solar, rising from less than 1GW in 2007.

The negative wholesale rates did not mean that Californians owed nothing for their power as it is based on averages and not single days. However, it does mean that Californian utilities and energy companies will need to rethink what the integration of such a high level of renewable energy means for the state’s electricity delivery and pricing.

In fact, the situation already has led to the curtailment of solar production during peak hours, with thousands of MWh of potential energy getting switched off, even as other non-renewable plants continue to produce. The introduction of grid-energy storage will be required to effectively supply 24-hour demand from renewable sources. 

7 October 2025
San Francisco Bay Area, USA
PV Tech has been running an annual PV CellTech Conference since 2016. PV CellTech USA, on 7-8 October 2025 is our third PV CellTech conference dedicated to the U.S. manufacturing sector. The events in 2023 and 2024 were a sell out success and 2025 will once again gather the key stakeholders from PV manufacturing, equipment/materials, policy-making and strategy, capital equipment investment and all interested downstream channels and third-party entities. The goal is simple: to map out PV manufacturing in the U.S. out to 2030 and beyond.
21 October 2025
New York, USA
Returning for its 12th edition, Solar and Storage Finance USA Summit remains the annual event where decision-makers at the forefront of solar and storage projects across the United States and capital converge. Featuring the most active solar and storage transactors, join us for a packed two-days of deal-making, learning and networking.
16 June 2026
Napa, USA
PV Tech has been running PV ModuleTech Conferences since 2017. PV ModuleTech USA, on 16-17 June 2026, will be our fifth PV ModulelTech conference dedicated to the U.S. utility scale solar sector. The event will gather the key stakeholders from solar developers, solar asset owners and investors, PV manufacturing, policy-making and and all interested downstream channels and third-party entities. The goal is simple: to map out the PV module supply channels to the U.S. out to 2027 and beyond.

Read Next

August 29, 2025
Chinese module maker JA Solar has launched DesertBlue, a PV module designed for desert and semi-arid regions. 
August 29, 2025
US-based climate insurance provider kWh Analytics has launched a new renewable energy insurance cover for extreme weather events.
August 29, 2025
US grid interconnection agreements grew by 33% in 2024, reaching 75GW, with three-quarters signed for solar PV and battery energy storage system (BESS) projects, according to a new report from energy market analyst Wood Mackenzie.
August 29, 2025
Meridian Energy and Nova Energy have established a JV to build and operate a 400MW solar plant in Rangitaiki near Taupo in New Zealand.
Premium
August 29, 2025
PV Tech Premium hears from Renewable Properties and Silicon Ranch about the new 'start of construction' rules for US solar projects.
August 28, 2025
Indian solar manufacturing firm INA Solar has broken ground on its fourth 4.5GW cell production plant in Narmadapuram, Madhya Pradesh.

Subscribe to Newsletter

Upcoming Events

Solar Media Events
September 16, 2025
Athens, Greece
Solar Media Events
September 30, 2025
Seattle, USA
Solar Media Events
October 1, 2025
London, UK
Solar Media Events
October 2, 2025
London,UK
Solar Media Events
October 7, 2025
Manila, Philippines