Biofuel companies in America are using technology from Europe in a bid to catch up with the rest of the world in green energy production.

Mike Casper, market development manager of American green energy firm Microgy, said the United States was "playing catch up" with European countries that have been developing green energy systems for years.

Speaking to Farmers Weekly at the World Ag Expo in California last week, Mr Casper said Microgy was using anaerobic digestion technology from Denmark, where it had been in use since 1999.

Microgy had installed the technology into four dairy farms in the United States so far, while 50 other farms had agreed to have digestion plants installed.

"The US has been slow to follow suit, but interest in developing green energy systems is growing and should really take off this year," he added.

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