Defined term
Avoided utility cost
Avoided utility cost is the charge a customer does not incur because onsite generation, storage, or a load change reduces a billable utility quantity under the applicable tariff.
Also known as avoided electricity purchase cost
economics · Concept code GS-CONCEPT-070 · Last verified August 20, 2026
Definition and boundaries
Definition
Avoided utility cost is the charge a customer does not incur because onsite generation, storage, or a load change reduces a billable utility quantity under the applicable tariff.
Definition claim verification: Verified August 20, 2026
In plain language
Use Avoided utility cost only after the cash-flow perspective, timing, contract structure, included costs, and omitted items are made explicit.
What it is not
It is not automatically equal to export compensation, wholesale avoided cost, or the entire pre-solar bill.
Decision context
Why it matters
Calculate it from the counterfactual bill and actual tariff components rather than multiplying all generated energy by an average rate.
Decision-context claim verification: Verified August 20, 2026
Information boundary
This page provides general educational context, not a site design, production guarantee, utility determination, contract interpretation, legal opinion, tax conclusion, or individualized financial advice. Verify property, equipment, utility, jurisdiction, program, and agreement details before acting.
Concept relationships
Affects
- Payback periodPublished conceptAvoided utility cost can affect how Payback period is evaluated
Primary sources
- National Renewable Energy Laboratory: A Comprehensive Review of Distributed Photovoltaic Compensation Mechanisms
Revision NREL/TP-7A40-78058 · Source event as of February 1, 2021 · Ontology accessed August 7, 2026 · Ontology verified August 7, 2026
- National Renewable Energy Laboratory: System Advisor Model Help
Revision System Advisor Model 2023.12.17 help · Source event as of December 17, 2023 · Ontology accessed August 20, 2026 · Ontology verified August 20, 2026
What to do next
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