Colorado’s Basalt Vista Neighborhood: “A Net Zero Affordable Housing Community”

October 8, 2019 | Nancy Kellogg

The town of Basalt, Colorado had a big problem.The local school district was struggling to attract and retain quality teaching staff due to low wages (30% less than comparable schools) and high local housing costs (30% more). But an innovative solution arose from this difficult situation that has resulted in an incredible community collaboration to build Basalt Vista, an all-electric, net zero, affordable housing community.

Roaring Fork Valley (RFV), Habitat for Humanity (H4H), and Community Office for Resource Efficiency (CORE) initially teamed up with a goal to provide the lowest possible utility bills for each resident. The community organizations subsequently developed a plan to build an affordable net zero community and make it a template for other communities to follow. The groups have utilized the town’s educators as promoters and advocates of the Basalt Vista collaboration.

The Plan for Developing Basalt Vista:

  • Electrification:
    • All home power and heating provided will be solely electric;
    • Replace traditional furnaces and water heating with cold climate heat pumps that are two to three times more efficient than electric baseboard heaters and provide efficient summertime cooling; and
    • All electric homes can help communities reach their climate goals and cut down on air pollution.
  • High-Performance Building Envelope:
    • Constructing airtight, well-insulated homes is a fundamental step for building net zero homes; and
    • H4H, the developer/builder, committed the project to meeting or beating International Energy Code Council’s (IECC) 2015 building code in Pitkin County.
  • On-Site Energy Production:
    • Meeting the total energy demand with onsite renewable energy production was the final component to construct this net zero, renewable community; and
    • Each home has an 8KW rooftop solar system that is grid connected to Holy Cross Energy (HCE).

HCE, the utility for the region, committed to pioneering an affordable net zero community template by making Basalt Vista a “Live Learning Lab”.

The first four homes built were equipped with Lithium Iron Phosphate (LiFePO4) batteries that provide on-site energy storage from the rooftop solar panels. HCE is conducting a pilot study with H4H and the National Renewable Energy Laboratory (NREL) in Golden, CO “hoping to prove how adjusting energy levels provided by solar arrays and battery storage at a home can be more cost-effective than modifying energy production at a centralized power plant.” The utility hopes to learn how to save its customers money by reducing the amount of energy their homes need to pull from the grid during peak periods when electricity rates are most costly. Sophisticated on-site storage and smart controls allows excessive daytime electrical generation to release back to the grid when needed.

By controlling and monitoring the four homes in the first two buildings of the community, the pilot study consisted of collecting five data points – solar PV, batteries, thermostat (heat pump space heater), heat pump water heater, and electric vehicle charging – in each home for four months. HCE started collecting these 20 data points, every five minutes, on June 1 before the homeowners moved in on June 29. As a result, they are constructing the subsequent net zero homes with energy produced by the pilot study homes, taking net zero construction to the next level!

Chris Bilby, HCE Research and Programs Engineer, was able to start transferring electricity from the batteries and solar panels to the grid during the last week of June 2019, just before two of the families moved into their homes. HCE is collecting data, utilizing two-way transfer of energy or (fuel flexing), and studying “islanding” or disconnecting this microgrid community from the larger grid. The microgrid’s creation and study has come with the added benefit of natural disaster protection. Basalt Vista’s on-site battery storage could prove useful in the event that outside electrical transmission is disrupted, as it was when the 2018 Lake Christine fire charred trees visible above the town and severed three of four transmission lines delivering electricity to Basalt as well as nearby Snowmass and Aspen.

On June 29th, 2019, the first two homes were dedicated to the Moran Bravo and Walker families in Basalt Vista’s net zero affordable housing community. These homes were the first the of twenty-seven net-zero homes, built over four years, and specifically slated for local school and Pitkin County employees. No natural gas lines were installed amidst this all-electric development, saving the project between $30,000 – $40,000. Ultimately, the project’s homes are affordable to purchase thanks to the community collaboration, and affordable to own because of the minimal electricity needed to operate them – household energy costs are approximately 85% less than the typical electric bill. The efficient structure, heating and cooling systems, water heating, and state-of-the-art efficient appliances (“smart” clothes dryers and induction cooktop stoves) were compatible with the constraints of on-site renewable electrical generation.

The homes priced at $270,000 – $395,000 for 2-, 3-, and four-bedroom units (1,150 – 1,675 sq. ft.).

All homes were built to IECC 2015 code and blower door tested. According to Scott Gilbert, president of RFV H4H, subsequent homes will be tighter because they are learning as they build. HERS scores (Home Energy Rating System) were viewed as an unnecessary expense by this development and unfortunately not funded. SWEEP staff worked to explain the value of the HERS rater as a third-party inspector to accelerate air leakage improvements and were able to connect a local HERS rater with RFV H4H. With the Department of Energy’s help, they were able to convince them to become DOE ZERH Partners.

The Department of Energy’s (DOE) Zero Energy Ready Home (ZERH) certification exists for homes with a HERS rating score in the mid 50’s or lower, (an ENERGY STAR or IECC 2012 code home + credentialed HVAC contractor for ducted systems) plus Indoor AirPLUS checklist and parts of the WaterSense and PV Ready checklists. The ZERH program overcomes weaknesses in code homes by addressing the important issues of indoor air quality, water efficiency, and PV readiness with checklists and third-party testing.

RFV H4H is also creating a homeowner’s manual, explaining the energy efficient features and the operation and maintenance of their homes.

A True Community Collaboration

Roaring Fork Valley H4H was the developer/builder of the Basalt Vista project and filled in the funding gaps along the way. The local school district donated the land (valued at $3.3 million), Pitkin County donated the road and utilities ($3 million), and the Community Office for Resource Efficiency (CORE) has pitched in $107,500 to date.