Unconventional oil and natural gas resources are an increasingly bigger piece of the pie for domestic energy companies, according to a new survey.

A survey of 100 U.S. oil and gas CFOs, which was done in November by BDO USA LLP, found that 25% see the discovery of significant new resource plays as the most important factor driving overall industry growth in 2012. A year ago only 14% of the energy CFOs cited new resource plays as the most important factor.

“We are in the midst of a significant global shift as nonconventional energy sources become more attractive to oil and gas companies,” said BDO’s Rocky Horvath, partner in the natural resources industry group. “These companies no longer view unconventionals as expensive and time-consuming but rather as a dependable and sustainable source of revenue. I expect that we’ll continue to see interest and investment in unconventionals as the U.S. takes center stage in this transformation.”

The findings are from the BDO 2012 Energy Outlook Survey, which examined the opinions of 100 CFOs in November.

As companies set their capital expenditure plans for 2012, CFOs are increasing their capital investments to explore unconventional areas. Shale investments were a top pick by 40% of those surveyed, followed by more environmentally friendly exploration and processing technologies (27%) and offshore exploration away from U.S. waters (7%).

Big improvements in technology have made shale gas and oilsands extraction lucrative production strategies in just a few short years, BDO noted. When it comes to increasing value for shareholders, 29% of the CFOs cited unconventional resources as the strategy they are most likely to pursue followed closely by cost-reduction programs (27%) and mergers and acquisitions (24%).

The latest survey also found that natural gas interest “fuels environmental concerns,” with 71% of the CFOs expecting global demand for gas to increase this year.

“As oil and gas companies aggressively seek new resources, business development strategies must also account for environmental ramifications and legislation,” BDO said. Among companies that experienced a “delay or termination” of oil and gas exploration or processing projects in the past year, more than half (56%) of respondents said federal or state environmental regulations were the cause.

“When asked to identify the one environmental concern that will most affect their business in 2012, 45% of CFOs put hydraulic fracturing at the top of their list. Other concerns include spills and pollution clean-up (26%), and greenhouse gas emissions (19%),” BDO said.

Wind power continues to be a “top” alternative energy source, said the CFOs. When considering alternative energy sources, wind power led, with one-third (32%) projecting that wind would be the “greatest alternative contributor to the world’s energy needs in the next five years.”

Other alternative fuels identified as the most viable by CFOs in the survey were biofuels (19%), hydroelectric (18%), geothermal (15%) and solar (14%). However, confidence in wind power has decreased in part because of a “rising interest in hydroelectric energy,” which saw a substantial increase in CFO interest over the last year (18% versus 9% in 2010).

Merger and acquisition (M&A) activity is projected to increase, said the CFOs.

“As unconventional production methods create new opportunities for U.S. oil and gas companies (including smaller industry players), merger and acquisition activity will remain robust in 2012,” said BDO. “The majority (52%) of CFOs surveyed expect M&A activity to increase in 2012 over 2011 levels, while 46% of CFOs expect activity to stay the same.

“Thirty-nine percent of respondents identify revenue and profitability as the primary M&A driver. Other catalysts include undervalued oil and gas assets (24%), a desire to increase market share (16%), geographic coverage (13%), and the push to become a fully integrated oil and gas company (7%).”