Solar in Boulder County

Xcel serves the City of Boulder, Louisville, Lafayette, Superior, Nederland and most of the unincorporated county; Boulder voters ended the city’s municipalization effort in 2020, and the franchise runs to 2041. Longmont Power & Communications serves Longmont and some areas just outside it, and Lyons operates its own small town electric system.

United Power serves parts of Erie and its mountain territory around Coal Creek Canyon, and Poudre Valley REA reaches into the northern part of the county. Confirm your utility on your bill; foothills roads sometimes cross a territory line.

Longmont systems installed or expanded on or after January 1, 2025 are credited for exports at a value-of-solar rate — below the retail price, above wholesale. Systems installed earlier keep retail credits through January 2040, so expanding an older system can move it onto the new structure.

Under value-of-solar, using your own power is worth more than exporting it. That tilts Longmont designs toward right-sizing the array and, where it makes sense, adding storage — a different recommendation than we’d give an Xcel customer in Lafayette.

Boulder County’s fire history is recent and personal: the CalWood Fire in October 2020 and the Marshall Fire on December 30, 2021, which was driven by downslope winds through Superior and Louisville. Those same winds are what trigger Xcel’s public safety power shutoffs, which have lasted from about a day to three days or more.

For homes in the foothills and in the wind-exposed neighborhoods east of the mountains, a battery that can carry the fridge, furnace blower, internet and medical equipment through a 72-hour shutoff is the practical goal we design around.

In unincorporated Boulder County, a roof-mounted solar system needs only a building permit — no land-use review. Ground mounts are different: systems under half an acre generally go through expedited site plan review and larger ones through full site plan review, unless they meet the county’s prescriptive standards for accessory ground-mounted solar adopted in January 2023, which allow approval with just a building permit.

The City of Boulder, Longmont, Louisville, Lafayette, Superior, Erie and Nederland each permit within their own limits. The City of Boulder also has its own solar access rules that protect sunlight on neighboring lots.

City of Boulder residents can get back part of the city sales and use tax paid on solar and — since April 2026 — battery system materials and permits, if they apply within 12 months. Boulder County’s EnergySmart program narrowed in 2026 to income-qualified households, covering 50% of efficiency or electrification project costs up to $2,000 for residents at or below 100% of area median income.

These are real, but they’re modest. We treat them as a bonus on top of a system that makes sense without them.