Jun. 10--The first time Sarah Shapiro walked into a Cisco Systems lab filled with racks of blinking routers and miles of multi-colored electrical wires, she felt like she was on a movie set.

The labs -- 1,500 worldwide -- are where Cisco tests its hardware and software and where Shapiro will spend much of the next two months figuring out ways the San Jose networking company can reduce energy and save money.

That's her assignment as an intern in a program that pairs top graduate business school students with companies to help implement energy efficiencies.

Called the Climate Corps, the two-year-old program of the Environmental Defense Fund has tripled in size this year, with 160 applicants vying for 26 internships at 23 companies across the country. And Cisco isn't the only Bay Area participant. Accenture, Advanced Micro Devices, eBay, Hewlett-Packard, Intuit, Salesforce.com and Shorenstein Realty Services also are hosting interns.

"We're really helping to create the next generation of business leaders who will automatically look at the environment as a business opportunity," said Elizabeth Sturcken, managing director of corporate partnerships at EDF.

Some companies, like Cisco, already have sophisticated energy efficiency programs. But for interns at smaller companies, even tackling low-hanging fruit -- retrofitting lighting, installing motion light sensors or turning off computers

and other electricity hogs when not in use -- makes an impact.

According to EDF, last year's class of seven MBAs helped identify efficiencies in lighting, computer equipment, and heating and cooling systems that could save a total of $35 million in net costs over five years, cut 120 million kilowatt hours of electricity per year, and reduce more than 57,000 tons of greenhouse gas.

Like many in the program, Shapiro doesn't have experience in energy efficiency. But most interns have some related background, such as corporate social responsibility or sustainability. Shapiro worked on climate change policies at an East Coast consulting firm.

"They come from the top business schools in the country which means they have proven leadership and analytic skills, and then we fill in the gaps," said Gwen Ruta, EDF's vice president of corporate partnerships. Interns are given a three-day crash course by energy professionals.

Key to the Climate Corps' success is that each intern is paired up with a mentor at the host company -- a data center or facilities manager, for example. Together, they review the company's energy profile, with the mentor giving the intern the resources to build a business case for operational change.