Nanosolar, a heavily financed Silicon Valley start-up whose backers include Google’s co-founders, plans to announce Tuesday that it has begun selling its innovative solar panels, which are made using a technique that is being held out as the future of solar power manufacturing.

The company, which has raised $150 million and built a 200,000-square-foot factory here, is developing a new manufacturing process that “prints” photovoltaic material on aluminum backing, a process the company says will reduce the manufacturing cost of the basic photovoltaic module by more than 80 percent.

Nanosolar, which recently hired a top manufacturing executive from I.B.M., said that it had orders for its first 18 months of manufacturing capacity. The photovoltaic panels will be made in Silicon Valley and in a second plant in Germany.

While many photovoltaic start-up companies are concentrating on increasing the efficiency with which their systems convert sunlight, Nanosolar has focused on lowering the manufacturing cost. Its process is akin to a large printing press, rather than the usual semiconductor manufacturing techniques that deposit thin films on silicon wafers.

Nanosolar’s founder and chief executive, Martin Roscheisen, claims to be the first solar panel manufacturer to be able to profitably sell solar panels for less than $1 a watt. That is the price at which solar energy becomes less expensive than coal.

“With a $1-per-watt panel,” he said, “it is possible to build $2-per-watt systems.”

According to the Energy Department, building a new coal plant costs about $2.1 a watt, plus the cost of fuel and emissions, he said.

The first Nanosolar panels are destined for a one-megawatt solar plant to be installed in Germany on a former landfill owned by a waste management company. The plant, being developed by Beck Energy, is expected to initially supply electrical power for about 400 homes.

The company chose to build its plant in southern San Jose, news that was cheered by local development officials. Much of the microelectronics industry created here has moved to Asia and new factories are a rare commodity in Silicon Valley.