How To Construct a Net-Zero Gas Station

In eco-friendly Portland, Oregon—where the first LEED-certified convention center was registered all the way back in 2004—gasoline is still necessary. The city’s motorists ranked number one in the United States in 2009 for new hybrid cars per capita (8.8 per every 1,000 households), but even hybrids need to be refilled every 400–600 miles. Meng-Hannan Construction, Inc., which specializes in gas stations, built or remodeled many such structures in 2010 and 2011, including the first net-zero facility for a City of Roses suburb. Take a careful look at how it was constructed—because there’s more green around the facility’s fossil fuels than meets the eye.

The Highland Chevron gas station is the first net-zero structure of its kind in the Portland, OR, area, and it’s all thanks to the work of Meng-Hannan. PHOTOS: KEN HAWKINS

1. Be a petroleum-retail specialist

In the Pacific Northwest, from Northern California to Alaska, Meng-Hannan is a go-to firm for the construction of petroleum-retail sites. It’s a demanding market with exacting permitting requirements, environmental standards, and business imperatives. “It really is a niche industry,” president of the firm David Hannan says.

In the case of the net-zero Highland Chevron facility (located in Beaverton, Oregon, and owned by Bob and Katy Barman), deconstruction of the existing petrol station had its own critical stages before construction of the new facility could begin. Luckily, Meng-Hannan’s entire field-supervisor staff is trained and licensed for fuel-tank removal, installation, and matrixing by the state’s Department of Environmental Quality (DEQ).

2. Tear down and decommission the fuel system

After a six-month permitting process, the existing gas station was demolished—carefully. Old underground fuel tanks and lines were triple-flushed in a cleaning solution that itself was properly disposed of off-site. The old fiberglass tanks were crushed on-site, and steel tanks were cut up and hauled away for recycling.

3. Excavate for and install the new fuel system

To accommodate new and larger tanks, the fuel-tank storage area was excavated deeper and wider. A filter fabric was used to separate native soil from pea gravel backfill that surrounds the new tanks, which themselves were anchored in place by rectangular concrete “dead-men” weights. These measures ensured that the tanks could move with seismic activity and that they wouldn’t float in a flood, preventing any release of gasoline into the environment. The integrity of the tank connections were all tested with air pressure.

4. Fit the tanks with trim and piping

Before the new fuel tanks were completely buried, each one was equipped with EPA- and DEQ-certified fiberglass turbine sumps, manholes, and automatic tank-gauging equipment—as well as double-wall, flexible product piping and fiberglass-reinforced plastic vent and vapor lines, which connected to the new dispenser islands. All sumps and double-wall fuel-system lines were pressure- and water-tested before final connection during the later stages of construction.

5. Construct the main building

The station convenience store was constructed at the same time. Because of the complexity of the structure—which included electrical conduits to the fuel area, concrete foundations, refrigerated units, plumbing, monitoring systems, and interior finishes—multiple subcontractors worked with Meng-Hannan on both the convenience-store and fuel-dispensing portions of the project. “It’s like an anthill at times, with a lot of activity,” project manager Brad Trebelhorn says. “I try to make sure it has more organization than chaos.”

6. Install the canopy

The roof over the fuel area traditionally serves two purposes: it acts as signage (for Chevron in this case) and protects the pumps from the elements. “This canopy is about 1,600 square feet—30 percent larger than what it replaced—to accommodate solar and green-roof components,” Trebelhorn says. “It also has to withstand strong winds and possible earthquakes.” Footings run six to seven feet deep, and the columns rise 17 feet from the ground.

7. Catch the rays and rain

Because the Highland Chevron facility’s canopy was a bit more complex, it added another week to the process. Pavement, fuel dispensers, and ground landscaping were the final elements built.

Photovoltaic solar panels (supplied by Dynamic Power Innovations, a local solar-power installer) now cover 60 percent of the roof, And even in this famously rainy region, they power all the facility’s lighting and signage, and they even supply an electric-vehicle (EV) charging station.

A 425-foot-deep geothermal well (supplied by Total Energy Concepts, a geohydronics firm) is the energy source for the store’s retail refrigeration units and the building’s HVAC systems. The eco-roof runs down the center of the fuel canopy, occupying about 40 percent of the surface area. The environmental features on the roof and below the ground are largely unseen. But the eyes of the world are still on the facility as a green gas station prototype. ABQ