In 30 years of putting up solar panels, Chuck Marken hasn't encountered anything quite like the two-humped top of Pittsburgh Truck House No. 34.

"I've never done an installation on a roof like that before," the consultant from Sandia National Labs told the city's new solar team yesterday, in advance of today's installation of a sun-powered water heating system on the double-Quonset-hut-shaped firehouse. "And I don't think I every will again, because Truck 34 is unique."

City officials, though, hope the $15,000 installation won't be unique, but will instead be the start of an effort to make numerous facilities solar, and to encourage businesses and homeowners to consider the green technology.

The push is comprehensive enough that Mayor Luke Ravenstahl is calling this Solar Week. On Thursday and Friday, some 140 municipal officials will come to the David L. Lawrence Convention Center for the U.S. Department of Energy's Northeastern Solar Cities Conference.

"The symbolism of the firehouse is important, because it is a practical use," said Mr. Ravenstahl. Unlike an exotic green building, it's something homeowners can relate to, he said.

"People will realize that, 'Wow, that's a solar panel on a firehouse? That's different.'?"

As Mr. Marken taught a dozen city plumbers, electricians and carpenters about solar water-heating systems, a truck pulled up at Truck House No. 34 and workers unloaded four panels, each 4 feet by 10 feet, through which water and heat-transferring glycol fluid will flow. Sun-warmed water will then flow into two 120-gallon collection tanks. A 24-watt photovoltaic cell will power the pump. Back-up gas heaters should kick in on only the dimmest of days.

The solar thermal water heater, as it's called, is "the best return on investment" currently available from sun power, said Karen Foltz, general manager and co-owner of McCandless-based Vox Energy Solutions, which is selling it to the city. It's also rare locally -- her company has installed only three before. "For some reason, people haven't caught on to solar thermal."

She has such a system on her house. The cost of a home installation can be trimmed by a $2,000 state rebate and a 30 percent federal tax credit, which her company can help secure.

The city expects to recoup its investment in Truck House No. 34 within 12 to 15 years, said city Energy and Utilities Manager Jim Sloss. But the project isn't just about dollars.

Employees trained to work on the firehouse roof will install another five solar thermal systems and perhaps two photovoltaic cells next year, Mr. Sloss said. In collaboration with Carnegie Mellon University, the city has tested the solar potential of 125 of its buildings. It hasn't yet finished ranking them according to roof quality, appropriate angle, age and absence of other utilities issues.

The installation should also generate publicity that will boost the local solar installation industry. The city is ready to take questions from residents and businesses on zoning and building inspection for solar systems via a new e-mail address, solarpgh@city.pittsburgh.pa.us.

The city will continue to draw on the expertise of Mr. Marken, whose bill is paid by the Department of Energy's Solar America program. Pittsburgh was named a Solar America city in 2007, making it eligible for grants and expertise.

"A lot of people think you really can't put a solar water-heating system in if you don't have a lot of sunshine," said Mr. Marken. Not true, he said. Even though it's often cloudy, Pittsburgh is "in the middle of the pack" in terms of solar radiation received, and a quality installation can provide a gallon and a half of hot water a day for every one square foot of thermal collector on the roof.

Ms. Foltz said the only adjustment she has had to make to her lifestyle is avoiding running loads of laundry at night.

The key is angling the collector so it gets the winter sun head-on, especially during the "solar window" of 9 a.m. to 3 p.m. daily, said Mr. Marken. That could be tricky on Truck House No. 34, but the plan is to place the panels between the two arched roofs.

If so, Pittsburgh will have something to show the visiting officials Thursday and Friday, bolstering presentations with titles such as, "Solar Thermal and Photovoltaics in Cold, Cloudy Climates" and "Permitting, Zoning & Solar Access Laws."

Another target audience is labor, which has adapted to the emerging green economy, and can profit from it, said Mr. Ravenstahl. "A roofer, for example, tomorrow is installing a solar panel, when he or she was previously installing a roof."

Looking for more from the Post-Gazette? Join PG+, our members-only web site. You'll get exclusive sports content, opinion, financial information, discounts from retailers and restaurants, and more. Our introduction to PG+ gives you all the details.