In case anyone else is wondering, here's the somewhat underwhelming list of the 737-9 ecoDemonstrator programme features:
HALON REPLACEMENT
A fire extinguishing agent is being tested in partnership with Meggitt PLC to replace Halon 1301 due to its ozone-depleting properties.
GREENHOUSE GASES
The ecoDemonstrator program is helping the National Oceanic and Atmospheric Administration measure greenhouse gas levels to help improve its climate modeling.
SUSTAINABLE CABIN
Using recycled carbon fiber for cabin sidewalls reduces waste going to landfills and can potentially make cabins quieter.
IMPROVED LIGHTING
A low-profile anti-collision light made by Hanwha Systems is being tested for its ability to improve maintenance reliability and efficiency from reduced drag.
SUSTAINABLE AVIATION FUEL
Every ecoDemonstrator program uses sustainable aviation fuel to reduce CO2 emissions.
QUIETER ENGINE
The engine nacelle has been modified to reduce current engine noise and address the different noise footprint of next-generation jet engines.
Boeing: ecoDemonstrator