OAKLAND -- For years, the solar industry has complained about wide disparities in the permitting fees California cities charge for solar installations on homes, schools, churches and retail stores, not to mention the amount of red tape and time associated with getting a permit processed.

Now nine East Bay cities -- Alameda, Albany, Berkeley, El Cerrito, Emeryville, Hayward, Oakland, Richmond and San Leandro -- have joined forces to streamline the permitting process, a move expected to save contractors and homeowners $850 to $3,500 per solar installation by reducing the need for outside engineering.

The collaborative effort, three years in the making, could serve as a blueprint for streamlining other sustainable energy permits, from home charging stations for electric vehicles to plumbing for graywater systems.

"In Germany, there's a two-page form to get a solar permit," Andrew Birch, CEO of solar installer Sungevity, said at an event announcing the new permitting plan Tuesday. "But in the United States, each city has different rules. Our customers typically experience a three- to four-month wait from the time they sign up to go solar to when they get the system installed. Standardizing the process will remove 25 percent of that time delay."

Birch noted that if customers get their solar systems installed more quickly, they will be more likely to refer friends and neighbors, which in turn will drive more solar adoption in the region. Sungevity, based in Oakland, has more than 300 employees and serves customers in nine states, the Netherlands and Australia.

The East Bay cities are all part of the East Bay Green Corridor, established to create a thriving region of green-tech innovation through the East Bay. Mayors of the nine cities first began talking about a regional solar permitting initiative in 2010.

"This was a collaborative effort involving nine cities, building departments, solar companies, the (Lawrence) Berkeley (National) Lab, the Governor's Office, and the U.S. Department of Energy," said Carla Din of the East Bay Green Corridor. "We're hoping this can be scaled statewide and then nationally."

The price of solar panels has plummeted in recent years. But consumers must pay not only for the panels but for so-called "soft costs" such as permit fees and installation charges.

Solar permit fees vary widely. Many cities in California charge a flat fee based on the time and effort city staffers spend reviewing them because building departments are often funded by the fees they collect.

The nine East Bay cities have solar permit fees ranging from $100 in El Cerrito to $615 in Richmond.

Under the new system, which will be rolled out in coming weeks, the fees charged by individual cities will not be reduced but six of the nine East Bay cities will have rapid, over-the-counter permitting while the other three promise a three- to seven-day turnaround. Solar contractors will use a "structural checklist" that includes items such as roof slope and rafter size, which will help city code officials determine if proposed solar installations are structurally sound. The checklist should remove the need for contractors to bring in structural engineers to review many residential projects.

In San Jose, most residential solar permits are already handled over the counter, with an average permit fee costing $310. In Milpitas, the average cost is $141.

"We issue between nine to twelve solar permits a month," said Keyvan Irannejad, building director for the city of Milpitas. "But there is no turnaround time: You can get the solar permit on the spot. The solar checklist and all of the necessary technical information is online."

Contact Dana Hull at 408-920-2706. Follow her at Twitter.com/danahull.

Current average fees for Residential solar permits
Alameda: $104
Albany: $211
Berkeley: $127
El Cerrito: $100
Emeryville: $250
Hayward: $300
Milpitas: $141
Oakland: $248
Richmond: $615
San Jose: $310
San Leandro: $170
Source: East Bay Green Corridor and Mercury News reporting