- Email: [email protected]
First flight by fuel cell?
OTHER NEWS
First flight by fuel cell? AeroVironment seemingly undaunted by its Helios setback, claims it has already flown a plane under fuel cell power alone. The vehicle, measuring only 380mm (15in) across, is one of an emer-
gent breed of micro air vehicles (MAVs) intended for use as surveillance platforms in urban environments and inside buildings. Christened Hornet and developed for the US Defense Advanced
Research Agency, it is a small flying wing powered by a 10W fuel cell which also acts as the main structural member for the wing. Hydrogen released when dry pellets are exposed to water carried on
board, reacts with oxygen drawn from the airflow over the wing, to release electrical energy. The operator, guiding the MAV by radio, has a channel available for controlling hydrogen release.
intensively used B737 could save up to 1,360 tons of fuel a year by having an APU powered from a SOFC rather than a small gas turbine. The company expects to test an experimental unit in a B737, initially to power the DC bus only, between 2005 and 2008. Because fuel stack power densities are unlikely to be high enough much before 2010 (at least 1kW/kg will be wanted, say officials - some ten times what is available now), Boeing is not expected to offer its new advanced passenger jet, the 7E7, with an SOFC APU initially. However after that, once electrochemically powered APUs do become estab-
lished, engineers may then be tempted to target fuel cell-powered primary propulsion, using hybrid systems initially to power large electric motors. On-board fuel cells offer the possibility to utilise energy derived from renewable resources, both for direct drive power, and to reform precursor fuel into hydrogen. RollsRoyce, also, is pursuing SOFC development. Rolls-Royce Fuel Cell Systems is working on natural gas-fuelled SOFC/gas turbine hybrids for stationary power generation applications initially, but envisages extension of the technology into transport, marine and defence applications.
Auxiliary power first While electric motors are unlikely to replace jet engines on larger aircraft any time soon, smaller auxiliary power units (APUs) could benefit from fuel cell technology, and hence renewables, a lot sooner. APUs are the small engines in the tails of passenger aircraft that provide hydraulic, electric and other services when the aircraft is on the ground and help start the main engines. Building on its participation in the Diamond Aircraft fuel cell demonstrator programme, Boeing intends to develop a fuel cell powered APU for demonstration on one of its B737 airliners. It plans to use a solid oxide fuel cell (SOFC), how-
ever, rather than the proton membrane cell planned for the motor glider, so that standard jet fuel can be used as a hydrogen precursor rather than using hydrogen itself. This strategy avoids issues of storing potentially dangerous hydrogen on aircraft. A proposed SOFC APU will deliver 440kW, enough to start engines on AC power and drive landing gear, environmental control and other systems that run from DC. Boeing says the fuel cell APU will be about 75% efficient, compared with a conventional APU of similar power that is typically 40 - 45% efficient. Calculations suggest that an
Web showcase BP Solar and its extensive network of partners provide total solar electric power solutions for industrial, commercial and residential applications throughout the world. With an unmatched track record of installations in more that 160 countries, BP Solar is a name that is synonymous with quality, reliability, performance and trust.
www.bpsolar.com To advertise in the Web Showcase contact Farry Ishaq: Tel: +44 (0)207 611 4150 or email: [email protected]
November/December 2003
REFOCUS
www.re-focus.net
19
First flight by fuel cell? AeroVironment seemingly undaunted by its Helios setback, claims it has already flown a plane under fuel cell power alone. The vehicle, measuring only 380mm (15in) across, is one of an emer-
gent breed of micro air vehicles (MAVs) intended for use as surveillance platforms in urban environments and inside buildings. Christened Hornet and developed for the US Defense Advanced
Research Agency, it is a small flying wing powered by a 10W fuel cell which also acts as the main structural member for the wing. Hydrogen released when dry pellets are exposed to water carried on
board, reacts with oxygen drawn from the airflow over the wing, to release electrical energy. The operator, guiding the MAV by radio, has a channel available for controlling hydrogen release.
intensively used B737 could save up to 1,360 tons of fuel a year by having an APU powered from a SOFC rather than a small gas turbine. The company expects to test an experimental unit in a B737, initially to power the DC bus only, between 2005 and 2008. Because fuel stack power densities are unlikely to be high enough much before 2010 (at least 1kW/kg will be wanted, say officials - some ten times what is available now), Boeing is not expected to offer its new advanced passenger jet, the 7E7, with an SOFC APU initially. However after that, once electrochemically powered APUs do become estab-
lished, engineers may then be tempted to target fuel cell-powered primary propulsion, using hybrid systems initially to power large electric motors. On-board fuel cells offer the possibility to utilise energy derived from renewable resources, both for direct drive power, and to reform precursor fuel into hydrogen. RollsRoyce, also, is pursuing SOFC development. Rolls-Royce Fuel Cell Systems is working on natural gas-fuelled SOFC/gas turbine hybrids for stationary power generation applications initially, but envisages extension of the technology into transport, marine and defence applications.
Auxiliary power first While electric motors are unlikely to replace jet engines on larger aircraft any time soon, smaller auxiliary power units (APUs) could benefit from fuel cell technology, and hence renewables, a lot sooner. APUs are the small engines in the tails of passenger aircraft that provide hydraulic, electric and other services when the aircraft is on the ground and help start the main engines. Building on its participation in the Diamond Aircraft fuel cell demonstrator programme, Boeing intends to develop a fuel cell powered APU for demonstration on one of its B737 airliners. It plans to use a solid oxide fuel cell (SOFC), how-
ever, rather than the proton membrane cell planned for the motor glider, so that standard jet fuel can be used as a hydrogen precursor rather than using hydrogen itself. This strategy avoids issues of storing potentially dangerous hydrogen on aircraft. A proposed SOFC APU will deliver 440kW, enough to start engines on AC power and drive landing gear, environmental control and other systems that run from DC. Boeing says the fuel cell APU will be about 75% efficient, compared with a conventional APU of similar power that is typically 40 - 45% efficient. Calculations suggest that an
Web showcase BP Solar and its extensive network of partners provide total solar electric power solutions for industrial, commercial and residential applications throughout the world. With an unmatched track record of installations in more that 160 countries, BP Solar is a name that is synonymous with quality, reliability, performance and trust.
www.bpsolar.com To advertise in the Web Showcase contact Farry Ishaq: Tel: +44 (0)207 611 4150 or email: [email protected]
November/December 2003
REFOCUS
www.re-focus.net
19