Rising energy costs and efforts to improve energy efficiency will be central drivers of the cleantech industry over the next five years, according to a poll of attendees at Ernst & Young's Strategic Growth Forum.

The poll results showed that nearly half of the approximately 140 respondents said rising energy costs are driving corporate interest in cleantech, more than any other factor, including concerns about emissions, recycling and resource scarcity combined. Nearly an equal amount, 42 percent, said energy costs will continue to have an outsized impact on their business over the next five years.

"These results demonstrate that the economics of energy continue to drive more and more businesses to adopt a cleantech strategy," said Joseph Muscat, Americas Cleantech Director at Ernst & Young LLP. "Cleantech is as much about addressing strategic corporate challenges as much as it is about responding to environmental concerns. Setting a corporate cleantech agenda is one of the top boardroom priorities today."

Half of all respondents said that of all cleantech initiatives, energy efficiency will have the greatest impact on their companies - as much as solar, wind, hydro, biofuels and others combined. More than half, or 54 percent, of businesses said they have changed their strategic plans or business processes to incorporate cleantech initiatives. Such steps include involving "green" messages into mission statements and communications, the adoption of new business processes, and development of measures and reporting on corporate sustainability.

The amount of spending on cleantech initiatives is gathering steam; while only 28 percent of respondents said their businesses are spending $1 million or more on cleantech now, 44 percent said they expect to reach that level within the next five years.

Other key details from the survey:

- 24% of respondents say they are devoting resources to measure their carbon "footprint;"

- Two-thirds of all respondents say market forces, not government regulations, will spur them to invest in and implement cleantech strategies;

- 22% say that cleantech initiatives at their businesses are led by those in the C-suite; another 16% say that they have designated "green teams" to initiate and implement various cleantech efforts.