Boeing announced additional orders from Dublin-headquartered ASL Aviation Holdings (ASL) for up to 20 additional 737-800 Boeing converted freighters to drive the company's environmental sustainability efforts.

In a statement, the American planemaker said the agreement is for 10 firm orders and 10 purchase rights.

"This new order is an important element of our fleet renewal programme, and we are delighted to expand our partnership with Boeing on the 737-800BCF," said Dave Andrew, chief executive, ASL Aviation Holdings.

"The 737-800BCF offers increased reliability and performance, and equally its lower fuel burn reduces our environmental footprint. This is very important to ASL as an aviation group committed to environmental sustainability in aviation."

Boeing said this is ASL's second order for the 737-800BCF and including options, will bring the organization's total 737-800BCF orders and commitments with Boeing to 40 aircraft.

The aircraft will be converted by Boeing at approved MRO sites including STAECO in Jinan, China, and at Boeing's London Gatwick MRO facility in the United Kingdom.

"We are honored to play a crucial role in the fleet renewal underway across ASL Aviation Holdings' operation," said Jens Steinhagen, director of Boeing Converted Freighters. "Boeing Converted Freighters support progress towards sustainability goals by providing operators like those under the ASL Group umbrella an economical way to replace less efficient, older-generation freighters."

The 737-800BCF carries more payload – up to 23.9 tonnes (52,800 lbs.) – and flies farther – 2,025 nautical miles (3,750 km) compared to 737 Classic freighters.