It's this balance, between business growth and environmental preservation, that sits at the heart of the city's efforts to encourage green building, without forcing developers to do it and possibly driving business away.

At its Feb. 24 and March 2 meetings, the city council discussed a city staff report proposing an incentive program for developers rather than requiring them to meet specific standards.

The incentive program offers more floor area for construction to developers who strive to meet Leadership in Energy and Environmental Design certification standards through the use of recycled materials, energy-efficient lighting systems and other methods of conservation.

A city ordinance providing these incentives could be in effect in less than a month.

Councilwoman Melinda Hamilton said she thinks requirements are going to be needed in the future.

"My hope is that over the next 10, 15 or 20 years that it is going to become a requirement, because it's going to have to be," Hamilton said. "It just makes sense, as the price of energy keeps going up, that at some point we're going to reach critical mass when it's actually cheaper to put in the initial investment."

Menlo Equities partner Jane Vaughan—who has built several buildings in Sunnyvale for Yahoo and Juniper Networks—said the incentives, while a step in the right direction, will probably not encourage any developers to change their plans to meet LEED standards; instead, they will merely reward companies who already intend to build green—of which there are few.

Vaughan said that right now, the initial investment might be greater than developers are willing to put in, for a benefit as small as a 5 percent floor-area-ratio increase. Although the report to the council said LEED certification only increases total construction costs by 1 percent, Vaughan estimated that in some cases, depending on location, the increase could be as high as 10 or 15 percent.

"Most companies that I deal with believe it is the right thing to do, and they have an environmentally efficient agenda, but if the final points [for certification] are going to be astronomical in price, it's not going to sell," she said.

Vaughan said that in one of her developments, an energy-efficient heating and air conditioning system cost $800,000, far more than the $24,000 the city estimated would be required to reach full certification.

In addition, Vaughan said the difficulty in getting LEED certification varies depending on location. In some areas, for example, reclaimed water lines are not accessible, preventing a company from reusing resources regardless of its plans.

"There may be an occasion where it is easy to do, and there may be another occasion where it's not easy to do, and it has nothing to do with what a developer wants to do," Vaughan said.

She added that in the end, a requirement may actually be the best way to get greener building.

But Hamilton said she worried that requiring contractors to meet LEED certification would potentially drive developers to areas that do not require more expensive projects.

"Personally, I would like to see a lot more buildings built green, but it's a balance between getting green buildings built and not driving businesses away," Hamilton said.

The council was required to hold two public readings of the ordinance in addition to giving its approval. By press time, the outcome of the March 2 reading was unknown.