Free to Use Datasets and Tools to Benchmark Rates and Analyze Affordability was presented as a NARUC CPI innovation webinar (published 2026-03-30) and moderated by Commissioner Christine Needo (appointed February 3, 2024). Speakers Daniel Zimnes and Thomas Bowen from the National Lab of the Rockies walked regulators, consumer advocates and other stakeholders through two open resources: the US Utility Rate Database (URDB) and the CAIRO modeling tool. URDB — established in 2010 with Department of Energy support and hosted on OpenEI — provides machine-readable residential, commercial and industrial tariffs (including EV and pilot rates), stores historical rates, and exposes data via a web app and JSON/CSV downloads. The Lab updates tariffs covering about 75% of U.S. load (~125 utilities) each year. Usage statistics for 2025 cited ~20,000 unique web users and ~14 million API hits. A current limitation is manual rate-sheet interpretation for updates; the team is exploring AI-assisted automation.

CAIRO (Customer Affordability, Incentives, and Rates Optimization) is a Python-based analytical model that ingests customer load data (hourly AMI or modeled profiles from tools such as ReSTOCK, IRPs, REEDS/Cambium), revenue-requirement inputs, and candidate rate/program designs to produce metrics on affordability, fairness, cost-reflectivity and cross-subsidization. Bowen presented applied studies: a Los Angeles Department of Water & Power analysis (2019→2035 scenarios) that tested on-bill financing, income-based fixed charges and expanded bill assistance; results showed on-bill financing could reach ~72,000 customers for insulation and ~150,000 for heat-pump water heaters, with a program adder ≈ $17/month and participating-customer bill reductions of ~9% and ~16%, respectively. A Massachusetts statewide exercise (2020→2035) modeled time-varying tariffs (critical-peak pricing/TOU), finding reduced system revenue requirements and net bill decreases for most customers, even while CAIRO’s bill-alignment test identified some cost-shifting where flexible and certain DER adopters avoided portions of their marginal costs. Both tools are free/open-source in intent: URDB is publicly accessible now (OpenEI) while CAIRO is primarily run by the Lab for partners today but is being refined, documented and made more user-friendly for third parties and PUC staff to run independently.