NREL Analysts Take a First Look at the Florida Duck Curve—and How Flexibility Could Help

New analysis examines how solar deployment may impact grid operations in Florida, an understudied but important market.

September 12, 2018

It’s been a decade since NREL discovered what’s now known as the “duck curve” when looking at how future deployment of variable solar might impact California’s power system. These days, NREL analysts are drawing upon data and experience from the Golden State to continue to examine key grid integration issues and geographies. The lab recently released new analysis for Florida—where solar is gaining momentum—that offers initial insights about how this resource may affect grid operations in the aptly named Sunshine State.

Graphic showing the modeled load shapes on Florida's power system with various PV penetration scenarios: 5% to 45%, over the course of a day.

The Florida “duck curve,” which shows the impact of increased PV penetration on potential net load in the FRCC system. (Actual net load factors in generator constraints and system flexibility options.)

Recently published in the journal Solar Energy by NREL analysts Elaine Hale, Brady Stoll, and Joshua Novacheck, “Integrating solar into Florida’s power system: Potential roles for flexibility” explores the possible impacts of significant solar photovoltaic (PV) deployment on Florida Reliability Coordinating Council (FRCC) operations in the mid-2020s—as well as ways to mitigate those impacts through additional system flexibility.

“Though it has deployed little solar to date, Florida has the eighth-highest rooftop PV potential of the states,” Hale said. “Our research looks at the ‘duck curve’ challenges that could come with high PV deployment in Florida, and how additional system flexibility might help Florida tackle these issues to achieve higher deployments of cost-effective PV.”

NREL’s Approach

For a range of high PV deployment scenarios, NREL looked at Florida’s electrical net-load variability (i.e., duck curve) challenges, and the associated reduction of PV’s per-unit value to the power system. Then NREL examined the ability of flexibility options—in particular energy-shifting resources like demand response and battery storage—to preserve that value and increase the economic carrying capacity of PV (which is determined by equating PV’s levelized cost of electricity or LCOE with the value it provides to the system).

Key Findings

  • At least 5% and more likely 10%–24% PV penetration could be cost competitive in Florida within the next decade, with baseline flexibility and all but the most pessimistic of assumptions.
  • A high level of demand response could boost the economic carrying capacity of PV by up to 0.5–2 percentage points, which is comparable to the impact of deploying a gigawatt (GW) of battery storage.
  • Adding 4 GW of battery storage could expand the economic carrying capacity of PV by up to 6 percentage points.

A First Look at an Understudied but Potentially Significant Market

Much of the detailed analysis of high solar penetrations—including the foundational research by NRELPDF that first showed the duck curve shape—has focused on California due to the state’s early adoption of PV. And other NREL workPDF has focused on how increased power-system flexibility could mitigate this loss of value in California. Less research, however, has focused on the unique qualities and lessons associated with high future PV penetrations in other emerging U.S. PV markets such as Florida.

“With several Florida cities pursuing significant renewable energy goals, this report provides key information, including the benefits and tradeoffs of different technologies and approaches, that state and local decision-makers may reference as they move forward with assessing how to achieve those objectives,” Hale said.

System-Level Flexibility and Other Strategies for Managing the Duck Curve

The new report evaluates options that power system planners and operators, particularly those facing conditions similar to the duck curve, may use to manage higher levels of variable solar on the grid. And NREL’s analysis isn’t finished with this look at the Sunshine State. The lab is continuing to research solutions to manage the duck curve—from flexible coalPDF to improved solar and wind resource modeling to getting essential reliability services from PVPDF.

Learn more about NREL’s electric system flexibility and storage studies.