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Reference hub
Independent home-energy research that started with rooftop solar. One worked example per state, the utility tariffs, the explainer topics, and adjacent pages on water heating and HVAC. The pages are ungated.
Examples
Worked examples
Utilities
By utility
- ComEd · Northern Illinois
- Ameren · Central and southern Illinois
- Naperville Electric · City of Naperville and adjacent unincorporated DuPage parcels served by the municipal utility
- We Energies · Southeastern Wisconsin
- Xcel Energy · Most of Colorado
- CORE · Douglas County including Castle Rock and Parker
- PGE · Northwest Oregon
- FGLP · City of Forest Grove residential and commercial customers
- Canby Utility · City of Canby residential and commercial customers
Adjacent research
Water and HVAC
Water heating and space conditioning are loads on the same electric bill the solar pages already price. Those explainers quote the existing tariff and production record. They are not a second city directory, and they do not add equipment prices or rebates.
Efficiency research hub →Methodology
How we research
Numbers on the site trace to NREL PVWatts, DSIRE, the Illinois Commerce Commission tariff record, EIA-861, and the Illinois Shines program filings, listed in the source bar at the top of each policy page. The full editorial policy, what gets cited, what gets refused, and how often each page is re-verified, lives on the methodology page.
Read the full methodology →