"Energy Efficiency is at the heart of energy affordability." Tony Earley, Chairman, CEO and President of PG&E Corporation


Zero Net Energy-The Future of Green Building

By Jonathan Marshall

Pre-fab homes by ZETA Communities are ultra-efficient and designed to be customized. (Photos courtesy of ZETA Communities.)

No man is an island, and few homes are either. Most rely on the outside world for electricity, natural gas, water, and other services. But more and more homes and buildings are now being designed to be more self-sufficient—indeed, to produce as much energy as they consume through a combination of solar generation and ultra-efficient design.

California designers and builders are taking the lead in this movement—both as a matter of environmental commitment and to meet an ambitious state goal of making all new residential buildings meet a “zero net energy” standard by 2020. Commercial buildings must target the same standard by 2030.

“There is tremendous value to the zero-net-energy paradigm,” said Peter Turnbull, who heads PG&E’s ZNE pilot program. “Because designers have to work within the limits of whatever energy they can produce on site, it forces them to design much more creatively, and to do things they wouldn’t otherwise think about.”

Learn more about the California model for energy efficiency

One of the leaders in this movement is ZETA Communities, a San Francisco-based builder of modular ZNE homes and commercial buildings. To keep costs down, it manufactures high-precision building components at a factory in Sacramento, then ships them to the site for assembly and construction.

Good insulation and tight seams help ZETA Communities build zero-net-energy homes and offices.

“We are taking a 12-month schedule down to three months, so developers save on construction financing and landholding costs, and begin getting revenue nine months earlier,” says Shilpa Sankaran, co-founder and vice president of marketing at ZETA Communities.

Factory construction also lets the company ensure high-quality seams and tightly sealed insulation to avoid air leakage and maximize energy efficiency, Sankaran said. By using quality materials and offering extensive customization, the process avoids the cheap look of old-fashioned pre-fab construction.

Since its founding in 2008, the company has completed 20 projects and 90 buildings throughout the Western United States, with a fast-growing pipeline of projects. One notable example is Tierra del Sol, a community of 22 solar-powered starter homes in Stockton with a starting price of about $160,000. They are projected to use about 45 percent less energy than similar homes, saving residents as much as $2,000 a year on energy bills.

The company has also manufactured new buildings for the Waldorf School in Davis, the main administrative building at the El Cerrito Zero Net Energy Recycling Center, and, finishing up this spring,SmartSpace®, a four-story, 23-unit apartment building South of Market in San Francisco.

Other Northern California companies are also pursuing a similar combination low-cost modular construction and state-of-the-art green features including high R-value insulation, EnergyStar appliances, and passive designs that exploit natural ventilation, lighting and heating.

San Francisco-based Project Frog, for example, built the Hunter’s Point Community Center, Crissy Field Center, a race driving school at Infineon Raceway, and various school projects around the country. It has received venture capital from GE, among other sources, to finance its expansion.

San Rafael’s Studio 101 Designs, on the other hand, focuses on single-family homes meeting the ZNE standard. It works with design and construction partners to create sustainable, modular homes ranging in size from 422 to 2,848 square feet.

In Southern California, the national builder KB Home is now offering ZeroHouse 2.0 models, with solar panels and advanced features that it claims will slash an owner’s energy bills by 40 percent compared to typical homes built to California’s current standards.

ZETA Communities’ Sankaran said she is working with other industry professionals and the California Public Utilities Commission to champion the state’s ZNE goals among  architects, engineers, builders, contractors and other stakeholders.

“We have a lot of work ahead of us,” she concedes. “The key will be demonstrating success and providing lessons learned from those successes to make it easy for other people to follow.”

One of her partners in this educational effort is PG&E, which provides incentives to energy-efficient builders through the California Multi-Family New Homes program. “PG&E has been instrumental in providing resources to our clients,” Sankaran says. “PG&E’s incentives absolutely help move the needle . . . and open doors and minds.”

Related PG&E programs, besides the ZNE Pilot Program, include the California Advanced Homes Program, the Multifamily Properties Program and the New Solar Homes Partnership and Savings By Design.

E-mail Jonathan Marshall at jvm9@pge.com.

This story originally appeared on pgecurrents.com.