What Does It Actually Cost to Live in a Net-Zero Home

Key Takeaways

• Total home energy usage (excluding EV) averages roughly 19,836–22,675 kWh per year.

• The home's solar system generates approximately4 5,552–45,972 kWh annually, more than double what the home needs.

• Heating and cooling costs average about $171 per month using an Arctic air-to-water heat pump.

• The water heater is the third-largest energy consumer in the home.

• Under Minnesota net metering, the home exports roughly 29,000-30,000 kWh to the grid annually, generating income of approximately $4,200-$4,500 per year at $0.10/kWh.

• The net annual energy cost is effectively negative. The home earns more from exported solar than it pays for imported grid electricity.

1. Three Years of Real-World Performance

Data tracking began in February 2023 when the system went live. The first year captures approximately 10.5 months of production. 2024 and 2025 reflect full calendar years.

• Solar production averaged: 44,464 kWh/annually

• Total household usage (home + EV charging): ~26,705 kWh/annually  

• Home (excluding EV): 20,520 kWh/annually

• Tesla Model 3 charging: 5,184 kWh (enough for ~20,000 miles at typical efficiency, on a car with 155,000+ total miles)

• Result: 100% of electricity needs covered by solar, plus a large net export (18,228 kWh/annual equivalent after accounting for seasonal imports/exports)

• Grid export total: 28,797 kWh/annually (mostly in peak summer months)

2. The Monthly Energy Breakdown

Without EV charging, the home consumes an average of about 1,700 kWh per month. That covers heating, cooling, hot water, lighting, cooking, appliances, and everything else in a fully electrified household. The heaviest months are January and July, when heating and cooling demand peaks. The lightest months are the spring and fall shoulder seasons.

The Arctic air-to-water heat pump with in-floor radiant heating and cooling handles climate control down to -20 degrees Fahrenheit. No backup furnace. No supplemental heat source. Just electricity from the roof.

3. What the Grid Sees

The home imports roughly 11,000-12,000 kWh from the grid per year, mostly during winter months when solar production drops. But it exports nearly 29,000-30,000 kWh back, primarily during the long, productive days of spring through fall.

Under Minnesota's net metering rules, those exported kilowatt-hours earn credits that offset winter imports. At an average value of $0.10 per kWh, the annual income from grid exports runs approximately $4,200-$4,500. That is not a rebate or a subsidy. It is energy the home produced and delivered to the grid.

4. Add the Car and It Still Works

EV charging adds approximately 5,000-6,000 kWh per year to total consumption. Even with the car, the home's total usage (roughly 26,000-28,000 kWh) stays well below annual solar generation (44,000-46,000 kWh). The system still produces 164-180% of everything the household needs, transportation included.

The home's Level 2 wall charger handles about 83% of the car's charging needs. The remaining 17% comes from Tesla Superchargers during longer trips.

5. The Upfront Investment vs the Ongoing Savings

Building a net-zero home does cost more upfront than a conventional build. The solar roof, battery, heat pump, super-insulation, and smart panel all add to construction costs. Federal tax credits available at the time of construction offset a significant portion of that premium.

But the ongoing cost picture is what changes everything. No gas bill. No propane bill. Minimal grid electricity costs after net metering credits. A home that earns income from the energy it produces. Over a 25-30 year system lifespan, the math strongly favors the upfront investment.

6. Could You Do This With an Existing Home

A ground-up build optimized for passive solar design will always perform better than a retrofit. But existing homes can move dramatically in this direction. Adding solar panels, battery storage, a heat pump, and a smart panel to an existing home can cut energy costs by 50-80% or more depending on the home's current condition and the improvements made.

The key is right-sizing the system for your actual usage and your home's solar potential.

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Whether you are planning a new build or upgrading an existing home, Greenway Solar can design a system around your goals, your climate, and your budget.