Operations – Green & Energy Efficiency
Utah Gets 5.5-6.5 Peak
Sun Hours a Day
At 4,200 feet elevation with 222+ sunny days a year, Utah’s Wasatch Front ranks among the best solar markets in the United States. The same climate that makes solar PV such a strong investment also makes high-performance building envelopes essential — because cold winters, intense summers, and extreme temperature swings demand buildings that hold their temperature efficiently. RainFire Builders delivers energy performance at every level: IECC code compliance as the floor, ENERGY STAR and LEED as the middle tier, and net zero as the ceiling — with solar PV, battery storage, and Rocky Mountain Power interconnection coordinated from the design phase.
GREEN & ENERGY SERVICES
THE UTAH SOLAR ADVANTAGE
Solar PV on the Wasatch Front –
Numbers That Make the Case
Utah consistently ranks in the top 10 states for solar production per installed watt. The combination of high sun hours, high elevation, and Rocky Mountain Power’s net metering program makes solar PV one of the highest-return clean energy investments available to Utah homeowners.
The solar resource on the Wasatch Front is exceptional by any measure. At 40.5°N latitude — the same as Denver and northern Spain — Utah’s valley communities sit in a solar-optimal zone. At 4,200 feet above sea level, the thinner atmosphere reduces the filtering of solar radiation compared to sea level, increasing the irradiance that reaches panel surfaces. Combine that with 222+ sunny days per year and the result is 5.5–6.5 peak sun hours per day — the metric that determines annual system production. Compare this to Seattle’s 3.5 peak sun hours, Chicago’s 4.0, or Miami’s 5.2 — Utah out-produces all of them.
A 7 kW residential solar PV system on a south-facing, 30-degree-tilt roof in Sandy, Utah, will produce approximately 9,500–10,500 kWh per year — enough to offset 80–100% of a typical Utah household’s annual electricity consumption of 9,000–11,000 kWh. The 30% federal Investment Tax Credit (ITC), available through 2032, reduces the net system cost by nearly a third. At current installed costs of $2.80–$3.50 per watt, the net cost after ITC for a 7 kW system is $13,700–$17,200. With annual utility bill savings of $1,400–$1,800, the simple payback is 8–12 years on a system warranted to produce energy for 25–30 years.
Rocky Mountain Power’s net metering (NEM) program credits excess solar generation at the retail electricity rate against future bills. Seasonal variation means most Utah solar homes produce surplus in spring, summer, and fall (when days are long and sun angles are high) that offsets winter bills (when the system produces less and heating demand is high). Monthly billing tracks the net — generation minus consumption — and credits carry forward for up to 12 months. RainFire Builders manages the interconnection application process with Rocky Mountain Power on every solar installation: the application must be submitted and approved before system energization, and the process involves utility engineering review, meter coordination, and approval that typically takes 2–8 weeks.
Battery storage (Tesla Powerwall 2 at 13.5 kWh usable, Enphase IQ Battery at 3.84–10.5 kWh, or Generac PWRcell) adds a layer of energy independence — storing excess solar generation for evening use (reducing grid draws during peak rate periods) and providing backup power during grid outages. Utah does not yet have widespread time-of-use (TOU) electricity pricing, but as Rocky Mountain Power transitions to TOU rates, battery storage systems that shift load to off-peak periods will produce increasing economic benefit. Even today, the backup power value of battery storage is meaningful in a state with increasing wildfire risk and grid stability concerns during extreme weather events.
OUR GREEN & ENERGY SERVICES
Every level of energy performance — from IECC code baseline through net zero and solar PV — is managed by RainFire Builders as an integrated part of project design and construction.
HOW WE DELIVER ENERGY PERFORMANCE
The RainFire Builders Green & Energy Process
Energy performance is designed in from the first conversation — not added at the permit application when the REScheck fails to comply or at the punch list when the blower door test results arrive. Here is how green and energy performance is delivered from concept to CO.
Why High-Performance Envelopes Deliver More Value in Utah Than Most Markets
Utah’s climate extreme is the driver. The Wasatch Front outdoor design temperatures span from -4°F (ASHRAE 99% design winter temperature for Sandy) to 98°F (ASHRAE 1% design summer temperature). A building envelope must maintain comfortable interior conditions across a 102°F outdoor temperature swing — and the physics are unforgiving: every degree of R-value or every air change per hour of leakage is a direct operating cost at both extremes. A home with R-13 walls and 6.0 ACH50 air leakage that costs $180/month to heat in January in Utah might cost $110/month in the same month in a mid-climate Southern city — because the outdoor temperature differential is greater and the duration of extreme temperatures is longer. The incremental investment in R-20 walls, R-49 attic, and 2.0 ACH50 air sealing pays back faster in Utah’s climate than in most U.S. markets, precisely because the performance demand is higher.
Mechanical ventilation is non-negotiable in well-sealed Utah homes. A building sealed to 2.0 ACH50 or below requires mechanical ventilation — the building does not ventilate adequately through random air leakage at low pressure differentials, and relying on occupant behavior (opening windows) is inadequate in Utah’s cold winters and poor-air-quality inversion events. ASHRAE 62.2 requires a minimum whole-building ventilation rate calculated from floor area and number of bedrooms. Heat Recovery Ventilators (HRVs) and Energy Recovery Ventilators (ERVs) provide mechanical ventilation while recovering 70–85% of the heat energy from outgoing stale air — delivering fresh air without the energy penalty of exhausting conditioned air. HRVs are preferred in Utah’s cold, dry winters (they recover heat without transferring humidity, which is appropriate in a dry climate). ERVs are preferred in humid climates. An HRV is standard in every net-zero and ENERGY STAR project RainFire Builders constructs.
Heat pump technology has transformed the calculus of all-electric homes in cold climates like Utah’s. Cold-climate-rated air source heat pumps (Mitsubishi H2i series, Bosch climate series, Daikin cold climate) maintain rated capacity at -13°F outdoor temperature — fully functional in Utah’s coldest nights. At a Coefficient of Performance (COP) of 2.5–3.5, a heat pump provides 2.5–3.5 BTUs of heat energy for every 1 BTU of electricity consumed — compared to a gas furnace’s ≤1.0 BTU of heat per BTU of gas combustion. Combined with a solar PV system that offsets the electricity consumption, a heat pump system in a well-sealed Utah home can produce net-zero heating at an operating cost lower than gas heating, even at current gas prices.
