A Green Stock with Upside Potential?

While wind stocks and solar stock may be too dangerous to touch, Cramer thinks you can speculate on green stocks that help increase energy efficiency and aren't reliant on government subsidies.

Ameresco fits that criteria, the "Mad Money" host said Friday. The largest independent energy services provider in the US, it focuses on energy efficiency. The company designs, engineers and installs equipment that reduces the energy costs of its customers' buildings by improving their heating, ventilation, cooling and lighting systems. It also provides more traditional energy-saving solutions, like roofing, window and insulation upgrades.

AMRC is a play on companies having to deal with high energy prices, which is a $5 billion market. He thinks this name in particular works because its services routinely deliver customers a 40 percent return on investment or more. If US companies spent $520 billion on building efficiency initiatives through 2020, they would end up saving $1.2 trillion on energy costs and also reduce greenhouse gas emissions by 1.1 gigatons a year, according to McKinsey.

Cramer first recommended Ameresco on July 20, which was the day before its stock offering. He called it an "IPO tortoise" because he expected it to climb slowly, but steadily in the long-term. AMRC priced at $10 the next day and as predicted, has since climbed by 23 percent. The stock has been trending lower lately because of budget pressures, but given the powerful trend in energy-saving, Cramer is not concerned. He thinks it has room to run.

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