People living in the new Tillamook Row housing complex in Northeast Portland are expecting to pay nothing in energy bills. About a mile away in the King neighborhood, a second, smaller home makes more renewable energy than the occupants use.

Across Portland are newly built dwellings and older ones retrofitted to be so environmentally smart -- with an airtight, super-insulated structure and energy-efficient features such as carefully positioned solar panels -- that, over the course of a year, they reward residents with zero energy bills and a carbon-free home.

Want to learn more? You can wander through a dozen green Portland homes from 10 a.m.-4 p.m. on Saturday, Oct. 19, during the Goal Zero Tour.

The event’s goal is to show “surprisingly simple, accessible and innovative strategies” homeowners can adopt to reduce energy bills, say organizers, who include nonprofit clean energy advocate Solar Oregon, environmentally driven builders, architects and designers like Green Hammer plus organizations that promote sustainable construction such as Passive House Northwest, Earth Advantage and the Home Performance Council of the Home Builders Association of Metropolitan Portland.

The nonprofit Community Energy Project will hand out educational materials on saving energy on a tight budget and reducing costs.

Residential buildings account for ​almost a quarter of all energy usage​ in Oregon, according to state government research, and zero-energy home design is an important strategy in climate adaptation, say tour organizers.

The self-paced, open house-style tour is concentrated in a five-mile area of North, Northeast and Southeast Portland, making it possible to ride a bike, scooter or bus to see the properties.

The tour, the final event of ​Sustainable Building Week 2019, includes dwellings that are net zero, on the path to net zero or zero-energy ready.

Green Hammer representatives will be at Tillamook Row, the first zero-energy housing for rent in the city, from noon-2 p.m. at 20 N.E. Tillamook St. to explain how the buildings were engineered to be highly efficient and what little energy is needed is served by an 82-kilowatt rooftop solar system.

Airtight walls, windows and roofs reduce heating and cooling needs by nearly 90 percent, they say. Energy Star appliances, hot water heat pumps, mini-split HVAC systems, LED lights and extra shading on the south side of the buildings help, too.

In addition to solar, which should produce all the power needed for condo owners and apartment tenants, a battery backup system in a communal building can store extra energy. Another reason not to fear a power outage: Each of the 16 units can pull electricity directly from a photovoltaic system during a blackout.

Tillamook Row also has three rain-catching cisterns to irrigate the community garden and much of the property's drought-resistant landscaping year-round.

Green Hammer has designed and built other net zero-energy homes and communities, including Ankeny Row, which produces, on average, 18 percent more electricity than it consumes over the course of a year, according to the firm.

Architect Jack Barnes designed a high-performance, net-zero secondary home, or accessory dwelling unit (ADU), in Northeast Portland’s King neighborhood that will generate more power than it uses. The project, which will be on the tour, was constructed by Eric Knott of Radius Design-Build.

Barnes says his client was already experienced with solar panels on site since she had them at a foursquare house. Her mission this time: “She wanted the ADU to be more comfortable and efficient than the older home,” says Barnes, who planned the home to take take full advantage of the electricity generated with new solar panels.

“I like this project because it shows that a net-zero home doesn’t have to be overly complex or expensive,” says Barnes. "The techniques we used are fairly standard, but we were able to achieve net-zero energy with just a few thoughtful design moves and a lot of attention to detail by the Eric’s team during construction.”

Tickets are $20 ($10 for Solar Oregon members) and available at bit.ly/GZT2019.

After the tour, ticket holders are invited to join builders, architects and nonprofits at Shine Distillery & Grill, at 4232 N. Williams Ave., to close out Sustainable Building Week 2019.

Energy-efficient traits

All kinds of buildings can be designed and built to reduce energy and fossil fuel use, but net zero-energy structures share these features engineered to cut down on heating and cooling demand:

Compact and simple building shape

Passive solar or onsite solar systems

Heat recovery ventilation systems to improve indoor air quality and provide year-round thermal comfort with heat recovery in winter and either heat transfer bypass or heat rejection in summer

Airtight construction

Super insulation

No thermal bridging

Advanced roof, window and door technology

Energy Star appliances

Extremely energy-efficient hot water heaters

Natural lighting and LED light fixtures

-- Janet Eastman | 503-294-4072

jeastman@oregonian.com | @janeteastman

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