Duck curve

Commercial-scale in electricity generation , the duck curve is a graph of power output over the course of a day That shows the timing imbalance entre peak demand and renewable energy production. In many energy markets the peak demand occurs after sunset, when solar power is no longer available. In locations where a substantial amount of solar power has been installed, the amount of power must be generated from sources other than solar or wind displays silhouette of a duck . [2] [3] In Hawaii, significant adoption of solar generation has the most pronounced curve known as the Nessie curve. [4] [5]

Without any form of energy storage , after-times of high solar generation Generating companies must Rapidly Increase power output around the time of sunset to Compensate for the loss of solar generation, a major concern for grid operators Where There is rapid growth of photovoltaics . [6] Storage can fix these issues if it can be implemented. Flywheels have shown to provide excellent frequency regulation. [7] Short term use batteries, at a large scale of use, can help to flatten the curve and prevent voltage fluctuation and can help to maintain voltage profile. [8] However, it is a major limiting factor for energy storage as each technique is expensive to produce and comparatively not energy dense compared to liquid fossil fuels.

Mitigation strategies

Methods for coping with the growth rate in the duck curve, which is becoming more serious in the solar generation grows, include: [8]

  • Installing more dispatchable generation
  • Orienting some solar collectors towards the west to maximize generation near sunset.
  • Energy storage including:
    • Pumped-storage hydroelectricity
    • Battery storage power stations
    • Solar thermal energy with thermal energy storage
    • Ice storage air conditioning
    • Use of batteries in electric vehicles for temporary storage ( vehicle-to-grid )
  • Energy demand management , including:
    • Transitioning to more efficient lighting systems, such as compact fluorescent and LED lighting
    • time-of-use pricing (TOU) and real-time pricing
    • Smart grid technology

A major challenge is deploying a solution that keeps growing with the growth of solar energy production. The effects of the duck curve have happened faster than anticipated. [9]


  1. Jump up^ “California ISO – Renewables Reporting” . . line feed characterat position 17 ( help ) |title=
  2. Jump up^ Paul Denholm, Matthew O’Connell, Gregory Brinkman, and Jennie Jorgenson. “Overgeneration from Solar Energy in California: A Field Guide to the Duck Chart” NREL / TP-6A20-65023. National Renewable Energy Laboratory , November 2015
  3. Jump up^ Wirfs-Brock, Jordan (2 October 2014). “IE Questions: Why Is California Trying To Behead The Duck?” . Inside Energy . Retrieved 29 October 2016 .
  4. Jump up^ “Charting Hawaii’s Spectacular Solar Growth” . The Energy Collective . Retrieved 2015-02-04 .
  5. Jump up^ “Hawaii Solar-Grid Landscape and the ‘Nessie Curve'” . February 10, 2014 . Retrieved 10 January 2017 .
  6. Jump up^ “What the Duck Curve Tells Us About Managing A Green Grid” (PDF) . . California ISO . Retrieved April 29, 2015 .
  7. Jump up^ Lazarewicz, Matthew; Rojas, Alex (10 June 2004). Grid Frequency Regulation by Recycling Electrical Energy in Flywheels . Power Engineering Society General Meeting : 2038-2042 . Retrieved April 29, 2015 .
  8. ^ Jump up to:b Lazar, Jim. “Teaching the” Duck “to Fly” (PDF) . HBP . Retrieved April 29, 2015 .
  9. Jump up^ “The California Curve Duck Is Real, and Bigger Than Expected” . 3 November 2016 . Retrieved 10 January 2017 .

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