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DOE OSTI · 2394637

SPECs Early-Stage Decision Model: User Manual

Casillas, Christian·Sandler, Simon·Cliburn, Jill K.
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Abstract

The SPECs Early-Stage Decision (ESD) model is central to the SPECs procurement solutions toolkit. The ESD model is an Excel-based spreadsheet model, which provides information about the economic and strategic value of a proposed battery-storage project or solar-plus-storage (solar-plus) project. The model can be used to explore combinations of storage-related project value streams in order to define a potential project, while educating co-op decision-makers about project benefits and costs. A sensitivity analysis function speeds the development of "what-if" scenarios. A gap analysis function solves for top-priority metrics and supports the inclusion of hard-to-monetize strategic values, such as the value of storage to defer costly system upgrades in light of increasing distributed solar and other distributed energy resources (DERs). Model outputs include the utility data, assumptions, and use-case scenarios that are recommended content for the requests for proposals (RFPs). The model may also provide an initial "sanity check" for RFP responses, supporting further discussions among utility staff, vendors and stakeholders. The ESD is not a "finance-grade" modeling tool, and users are cautioned to be mindful of its limitations, but the model has been reviewed by users, who recommend it as a way to drive faster and better project design and planning, as well as to facilitate better communications with vendors, grid partners, and stakeholders.

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14 SOLAR ENERGY29 ENERGY PLANNING, POLICY, AND ECONOMYbattery storagedecision modeldemand chargeenergy storage service agreementESAPPAproject design and planningSAMsolar power purchase agreementsolar+storageSystem Advisor Model

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Casillas, Christian, Sandler, Simon, Cliburn, Jill K.. 2021-07-01. SPECs Early-Stage Decision Model: User Manual. https://doi.org/10.2172/2394637

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