Large companies looking to hedge their exposure to rising energy costs are employing a larger number of banks to execute their commodity trades due to tighter credit markets, a survey released by Greenwich Associates showed on Wednesday.

The consultancy's global survey of more than 300 large firms showed that their relationship with their lenders is now almost as important as the bank's commodity market expertise, with airlines and large industrial companies putting an increasing premium on access to credit.

The banks that have built out commodities platforms are eager to leverage lending relationships to win high-margin derivatives trades, Greenwich Associates consultant Andrew Awad said in the report.

Some companies, meanwhile, have seen credit lines cut and are adding additional commodities providers that have invested in their platforms and are willing to lend.

The report said the average number of dealers used by major firms in 2011 had risen to 5.0 from 4.7 in the previous year, with airlines, chemical companies and both public and private utilities showing the largest increase in the number of banks they trade through.

But Greenwich warned tighter regulations may force banks to cut back on their commodity offerings or move into more specialized areas in the coming year, reducing competition and possibly restricting the ability of firms to hedge their exposure more than one year out.

Companies might well find that 2011 will represent the high point in terms of banks' pricing, product availability, coverage, and credit provision relating to the OTC commodities derivatives business, Greenwich Associates consultant Woody Canaday said in the report.

As such, companies should be reviewing their own dealer relationships to ensure that they are doing business with the strongest service providers.

The number of companies with hedges lasting one to three years on average fell to 45 percent from 49 percent last year, the survey showed, while the percentage of those placing short-term hedges of just one to three months jumped to 12 percent from 4 percent.

The Greenwich Associates 2012 Energy Commodities Study surveyed 306 individuals at corporations around the world between September and November last year, the report said.

(Reporting By David Sheppard; editing by Jim Marshall)