Storytelling in the U.S. Power Sector: NREL’s Standard Scenarios

By Wesley Cole, NREL Energy System Modeler and Analyst

Researchers in the collaboration room of the Energy Systems Integration Facility (ESIF) at NREL in Golden, Colorado, study feeder topography of a distribution management system power grid. Photo by Dennis Schroeder, NREL

Stories are a pretty fundamental part of my household. My wife’s degrees are in English and creative writing, so it’s no wonder that she has made books and stories a core part of our children’s learning experience. On our last count, she and our kids read 5,000 children’s books in the course of one year (the librarians appreciated our family helping to keep up good circulation).

I heard about (and read with our kids) many of those stories, and part of that experience now impacts me as a researcher at the National Renewable Energy Laboratory (NREL). In developing the lab’s annual Standard Scenarios report with the help of a talented team over the past five years, we have taken a similar approach to exploring many power-sector stories — with meaningful lessons to share.

Generation across the suite of Standard Scenarios for the fuel types indicated. The Mid-case scenario is shown as the blue dashed line. Other includes biopower, concentrating solar power, geothermal, hydropower, and landfill gas.

Each year, we use NREL’s sophisticated modeling tools to generate dozens of standard scenarios for the U.S. power sector (the scenarios are “standard” because they are generally the same set of conditions that we refer to frequently). These scenarios by themselves are useful to many people, but the suite of scenarios also provides a basis for research, industry, and policy decisionmakers to understand potential stories unfolding in the power sector.

For example, in our 2019 report, we looked at how resource adequacy (i.e., making sure you have enough generation capacity to meet demand) is maintained across the scenarios, especially in those that have very high deployment of wind and solar generators. We found that non-variable generators, such as thermal plants and storage facilities, provide the bulk of the contribution toward resource adequacy even when most of the annual energy might be from wind and solar generators.

Total capacity (top) and planning reserve provision (bottom) by fuel type in the High Renewable Energy (RE) Cost, Mid-case, and Low RE Cost scenarios. The planning reserve provision is the capacity that contributes toward the planning reserve margin.

We also explored how changes in regional generation mixes are driven by technology costs, state policies, and resource quality across the scenarios. We found that while states may align with broader national trends — such as moving from coal toward either natural gas, wind, or solar technologies — there is still meaningful regional variation within the national grid.

The Standard Scenarios analysis uses the latest technology cost and performance data from NREL’s Annual Technology Baseline, as well as two of NREL’s flagship energy modeling tools: the recently publicly released Regional Energy Deployment System (ReEDS) model and the Distributed Generation Market Demand (dGen) model. The ReEDS and dGen models project utility-scale power sector evolution and distributed photovoltaic (PV) adoption, respectively, using the Standard Scenarios definitions to specify model inputs. The ReEDS model takes a system-wide, least-cost approach when making decisions, while dGen uses a customer-centric adoption approach.

Map of Variable Renewable Energy (VRE) penetration by state in the Mid-case, High RE Cost, and Low RE Cost scenarios in 2050. Note that states with 100% clean energy standards can use non-VRE resources such as hydropower, geothermal, biopower, CSP, and nuclear to fulfill their clean energy requirement.

Alongside the report, the Standard Scenarios Results Viewer is an interactive tool that allows users to conduct their own independent analysis while drawing on the modeling and expertise used to create the scenarios. Users can compare how different technologies — such as biopower, nuclear, or land-based wind — contribute to total estimated electricity generation or capacity over time, and use the results to shape their own power-sector storytelling.

There are many more stories discussed across the five years of Standard Scenarios reports published to date, with even more stories yet to be written. We continue to use these scenarios to help explain stories that we think provide useful information, and we are happy to publish the scenario results and modeling tools so that others can understand and share power sector stories important to them.

For more information on the 2019 Standard Scenarios, join our webinar on Jan. 9, 2020, at 11 a.m. Mountain Time. My fellow report author Trieu Mai and I will discuss project insights, challenges, and applications, with a Q&A session to follow.