The credit-carryover question decides everything
Under Colorado’s net-metering statute for investor-owned utilities (C.R.S. 40-2-124), Xcel and Black Hills customers can bank surplus generation as credits that carry forward, and Xcel lets customers choose between an annual payout and indefinite rollover. For a summer-empty, winter-busy home, that means July surplus pays for December use at retail value. A system sized to the annual total works cleanly.
Co-ops and municipal utilities set their own rules beyond the 10 kW state floor. Many carry credits month to month within a year and then true up, paying leftover kilowatt-hours at an avoided-cost rate that is a fraction of retail. On that tariff, the summer surplus from an empty house is mostly given away. We size to consumption instead, the payback stretches, and we tell you where it lands. Ask your utility for its current tariff; this is the single most important number for a second home.
Low winter use, high winter risk
A second home set to 50°F with the water off uses very little in winter, and a small system covers it. What it can’t afford is an outage that kills the heat while nobody’s there. A frozen pipe in an unoccupied house is the failure mode every second-home owner fears, and it’s the strongest case for a battery on a property with modest bills.
A Powerwall 3 or SigenStor on a backup-loads panel keeps the furnace or boiler controls, thermostat, heat tape, well pump and sump running through a multi-day outage, recharging from the roof in daylight. Colorado’s state battery incentives — sales-tax exemption through 2032, a 10% income-tax credit for tax years through 2026 — apply to residential batteries as of September 2026; confirm with your tax advisor whether they apply to a home you don’t occupy full-time.
Snow, shade and the mountain roof
Most second homes we install on are in the mountains, and mountain roofs are steep, complicated and often shaded by spruce. Steep pitch helps snow shed; north or east faces and tree shade hurt. We model production for your actual roof and shading rather than using a Front Range average, and we specify racking rated for your county’s snow load.
A detached garage, a shed roof or a ground mount in a sunny clearing sometimes beats the house roof outright. Because nobody is around to clear snow, we favor layouts that clear themselves: south-facing, steep, away from roof valleys where drifts collect and slide.
Watching it from a different zip code
You won’t be there to notice a tripped breaker or a snow-buried array. The Enphase, Tesla and SigEnergy apps report production per panel, consumption, battery state and grid status in real time and send alerts when something stops. We recommend owners check the app monthly and after any big storm.
Set expectations honestly: a mountain array may report near-zero output for a week after a storm and then recover on its own. That’s normal, not a fault. What isn’t normal is an inverter offline in July, and the app will show it so you can call us.
One practical note: a second home’s address and the mailing address for the utility account are often different. Give us both, along with the utility account number, so interconnection paperwork doesn’t stall.
What to do next
- 1Get 12 months of bills and ask the utility how it credits surplus generation and when it trues up.
- 2Tell us your occupancy pattern (which months, roughly how many days) so we can compare production against use.
- 3Send roof and tree photos, ideally in winter, and the county for snow-load requirements.
- 4Decide whether freeze protection during outages justifies a battery; list the circuits that would need it.
- 5Give us the property address, the utility account mailing address and the account number for interconnection.
Figures are honest ranges from our Colorado pricing and public data, not a quote. Utility rules and incentives change — we confirm the current ones before any design.
FAQ
Questions we hear
My second home is in Xcel territory. Is solar a good fit?
Usually yes. Surplus credits carry forward, so summer production while you’re away pays for winter use while you’re there. Verify the current rollover rules; they’ve been stable but can change with rate cases.
My mountain home is on a co-op. Should I still add solar?
Often, but sized differently. If the co-op pays annual surplus at a low rate, we size to what the home actually uses instead of overbuilding, and the payback runs longer. Ask for the tariff; we’ll show you the honest number.
Will the panels stay buried in snow all winter while I’m gone?
Not usually. Steep south-facing arrays shed within a few days of sun. A week of zero output after a big storm is normal. We design layouts that clear themselves because nobody will be there with a roof rake.
Can a battery keep pipes from freezing during an outage?
It can keep the essentials that prevent freezing — thermostat, furnace blower or boiler controls, heat tape, well pump, sump — running for a day or more, longer with solar recharging. It won’t run electric baseboard heat for the whole house.
Do I still get a tax credit on a second home?
The federal residential credit (§25D) ended for systems placed in service after 2025, first home or second. Colorado’s battery incentives still apply to residential batteries as of September 2026. Ask your tax advisor about your situation.