Honeywell upgrades APU to reduce CO2 emissions

Honeywell upgraded its auxiliary power unit (APU) on the Boeing 737 aircraft, known as High Efficiency Mode, or HEM enabling it to reduce CO2 emissions by up to 2%, increasing efficiency and minimising fuel consumption.   Heath Patrick, president, Honeywell Aerospace, said: “An airline with a fleet of 50 737s could realise as much as $450,000 in annual fuel savings and reduce its emissions by up to 1,100 metric tons of CO2, depending on operating conditions.”   HEM is enabled by a “highly efficient” diffuser, controlled by intelligent software which regulates airflow to the APU compressor section, says Honeywell.