Duke Energy’s IRP ‘ignores the synergistic benefits between solar and storage’, says E3

Share on facebook
Facebook
Share on twitter
Twitter
Share on linkedin
LinkedIn
Share on reddit
Reddit
Share on email
Email
Image: Duke Energy.
Image: Duke Energy.

US utility Duke Energy should refile its 2020 integrated resource plan (IRP) to effectively allow for the diversity benefits of solar and storage to be captured, it has been argued by energy consulting firm E3.

A new report from the consultancy said that Duke’s capacity expansion methodology considers solar and storage independently, at different steps of the process, ignoring the synergistic benefits that exist between the two, meaning the IRP “likely fails to identify a least-cost solution for its ratepayers”.

E3 said IRP portfolio optimisation should be carried out in a single step, in which all components of the capacity expansion are optimised at the same time, as opposed to sequentially. This is so that the interactive effects of renewable and storage resources can be captured when they are evaluated simultaneously.

Duke’s sequential approach that analyses firm retirements, renewable additions and storage additions in isolation from one another “fails to capture” key benefits that the model can only recognise when these resources are evaluated jointly, according to E3, meaning the approach “artificially reduces the amount of solar and storage built on the system as the model is unable to accurately account for the synergistic effects”.

Meanwhile, evaluating the benefits of solar and storage at separate points in the capacity expansion process could lead to other technologies being chosen at a higher cost, the report claimed.

Details of the IRP were announced last September, revealing six paths for the utility’s power generation portfolio up to 2035. The models put solar capacity anywhere between 8,650MW and 16,400MW, while the energy storage fleet is expected to reach between 1GW and 7.4GW depending on the renewables adoption rate.

The E3 report recommends that Duke re-run the capacity expansion component of its IRP using a single-step optimisation methodology that co-optimises all resources and policy constraints simultaneously. “This is the only way to ensure that the synergistic properties of solar and storage be represented, and a true least-cost solution can be found,” the report reads.

Over the next five years, Duke’s capital plan foresees the utility spending US$59 billion, of which 70% will be focused on investments in clean energy and the grid infrastructure that supports it. Speaking in a conference call with investors last week, CEO Lynn Good said the capital plan places the firm “at the forefront of clean energy at scale”.

Duke is aiming to cut carbon emissions by at least 50% by 2030 and achieve net zero status by 2050.

Read Next

March 4, 2021
A round-up of the latest solar project news from around the world, including updates from Hanwha Q CELLS and Capital Dynamics.
March 3, 2021
Iberdrola is progressing with efforts to develop three solar farms in Spain’s Valencia region that will have a combined capacity of 450MW and require an investment of more than €235 million (US$284 million).
March 1, 2021
Endesa, through its Enel Green Power España subsidiary (EGPE), has started construction work on four PV projects in Spain that will have a combined capacity of 180MW and cost €125 million (US$150 million) to develop.
March 1, 2021
An Australian solar-plus-storage project that aims to supply 20% of Singapore’s electricity demand has been marked as a priority initiative by advisory group Infrastructure Australia.
March 1, 2021
Xcel Energy has announced plans to double its renewables and battery storage capacity in Colorado by 2030, as the utility progresses with efforts to reach 100% carbon-free electricity generation across its service area by 2050.
February 26, 2021
EDP will focus on North America to ramp up its solar capacity in the next five years as part of a new strategic update that will see the Portuguese utility target more than 50GW of renewables additions by 2030.

Subscribe to Newsletter

Upcoming Events

Solar Media Events
March 9, 2021
Solar Media Events
March 17, 2021
Solar Media Events
April 13, 2021
Solar Media Events
April 20, 2021