Welcome

Welcome to the NC Energy Storage Study website.  This site contains information related to the North Carolina energy storage study, which was mandated through the NC General Assembly’s authorization language from HB 589 (2017) (see Part XII, Section 12). The NC Policy Collaboratory selected NC State to conduct the study.

The NCSU research team drafted a proposal in late 2017 that outlines our approach to this study. Our final report was submitted to the NC General Assembly on December 3, 2018. In addition to the report, we will be making our data and models publicly available. Items will be posted below as they become available. Note that models and data are distributed in the hope that they will be useful, but without any warranty.

Deliverables

Our final report is now available for public download. Here is the associated press release.

Benefit-cost spreadsheet. This spreadsheet contains the benefit and cost information cited in the study. The ‘B-C summary’ tab contains the benefit ($/kWyr), cost ($/kWyr), and break-even cost ($/kWh) for all 432 scenarios we ran. The remaining worksheets contain the technology-specific cost and performance information we used to derive the revenue requirement for each technology. For more information on the cost calculations, see Section 4.6 of our study.

End User Services (Behind-the-Meter). These spreadsheets calculate the energy storage benefit for a customer site (large, medium, small, residential).  The storage is located behind the electric meter and controlled to limit a customer’s peak demand or coincident peak demand each month.  In the case of solar PV plus storage, the battery is charged from the solar PV and in the case of storage only, it is charged from the grid.  Each scenario is compared to a base case load profile, taken from NREL’s System Adviser Module software, which represents a typical customer load.  In this way, the net benefits from storage are comparable across the scenarios, regardless of the tariff used.

Distribution Services. This VBA-enabled Excel tool was used for the distribution system analysis. This analysis covers three cases where storage could provide value on the distribution system: capacity deferral and peak shaving, reliability enhancement, and voltage control for high penetrations of solar PV.

Frequency Regulation. This download includes the PJM regulation signal and prices, in addition to the NY-ISO regulation signal. The NY-ISO price data is posted by day and can be downloaded from their website here. The model used to perform frequency regulation is undergoing development as part of a PhD thesis. The full algebraic formulation of the model is given in Section 6.6 of the report.

Bulk Energy Time Shifting and Peak Capacity Deferral. The analysis was conducted with an open source energy system model called Tools for Energy Model Optimization and Analysis (Temoa), developed at NC State University. The link points to a zenodo archive that contains exact copies of the model code and data used to conduct the analysis. Additional information on how to run the model is available on the Temoa website.