PORTLAND, Ore. To drivers passing by on Martin Luther King Jr. Boulevard, the structure rising above the parking lot is mostly unremarkable. But to the eco-elites who gathered in this green-leaning city in June for its unveiling, it represented a blueprint for the filling station of the future.

The roof of the 12-foot-tall steel canopy, built by EV4 Oregon, is covered with solar cells that generate power for a pair of ECOtality Blink Level 2 electric-vehicle chargers at the base. The facility is connected to the electrical grid, so any excess electricity from the solar cells can be sent to the local utility.

The canopy is more than just a sunny-day design: other installations will include an underground bank of batteries to store electricity for distribution after dark. As the electric vehicle population grows, more canopies can be added to create a covered parking lot.

“This is the future, my friends, and it will make a difference,” said Jeff Cogen, chairman of the Multnomah County Commission and one of several dignitaries to attend the ribbon-cutting ceremony. “Hopefully, in 20 years, we can look back and say, ‘I remember when these were introduced.’ ”