US-based Next Fuel Inc said it has earned its first revenue of US$160,000 from licensing out its coal-to-gas (CTG) technology and payments for initial testing units completed in China.

The Sheridan, Wyoming company, which develops and commercialises clean energy and environmental technologies, said it received the payment from its Chinese strategic partner, Future Fuel Ltd, earlier this year.

It expects to receive further payments upon the production of biogenically generated methane gas from drilling additional gas generating units later this year when the partner complete evaluating appropriate locations.

Next Fuel said its patent-pending CTG technology converts low-grade coal, such as lignite, into clean-burning natural gas through the introduction of nutrients, via a low-pressure pumping system, to the wide range of microorganisms that naturally exist in coal deposits. The proprietary nutrients stimulate the microorganisms, which in turn consume certain carbon-containing compounds in the coal and "exhale" biogenic natural gas as a byproduct.

Robert Craig, NextFuel's chairman and CEO, said:

"We are very pleased to achieve this revenue milestone in our first commercial CTG project in China and anticipate a lengthy and prosperous relationship with our strategic partner, Future Fuel.

"The injection of nutrients is currently underway, and we look forward to the generation of commercial quantities of methane gas from the project later this year."