You must listen to earnings conference calls, Cramer said Monday. Or at least read the transcripts after. Because within them is a wealth of information that can help you make money.

Throughout July heard one term thrown around again and again: energy efficiency. Apparently the companies that help others monitor and save energy, especially those that make the power grid “smarter,” are doing especially well.

“Power management, fuel management, power quality—these have become the global megatrends of our era,” Cramer said, “as the cost of finding, distributing and using energy keeps increasing. Governments around the world are adopting policies to incentivize energy efficiency.”

Look for Cramer to highlight these companies all week, a series he has dubbed “Grid of Gold Week.” The first, and one of his longtime favorites, is the diversified industrial Eaton .

Eaton makes everything from fluid power systems and electric control products to fuel-efficient transmissions and hybrid engines for trucks, as well as aerospace components. About half of the business is electrical, where the company helps customers improve the efficiency of buildings, plants and other infrastructure, and management on the conference call said demand for these power-management solutions has never been greater.

Cramer’s also a big fan of the CEO, Sandy Cutler. Under his leadership, ETN jumped 61% between Cramer’s first recommendation on Oct. 22, 2008, and Nov. 30, 2009, when Cutler appeared on the show. And since then the stock is up another 27%.

Still, Cramer thinks Eaton goes higher. To find out if he’s right, and to hear more about the golden grid, he invited Cutler back to the show. Watch the video for the full interview.

Call Cramer: 1-800-743-CNBC

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