News | 15.12.2015
All-electric propulsion systems like the one on Eutelsat 115 West B, reduces a satellite’s launch weight by 40 percent or more but delays its arrival in geostationary orbit by months.
Eutelsat plans to reduce the cost of its future satellites by some 20 percent initially, with more savings to come, as it seeks to adapt to a changing competitive environment.
The immediate reductions are being made possible by a combination of all-electric satellite propulsion and a more-competitive launch-service environment.
All-electric propulsion reduces a satellite’s launch weight by 40 percent or more. As long as Eutelsat’s business plan for the satellite can sustain a months-long wait to arrive in geostationary orbit, rather than a few weeks with conventional chemical propellant, the trade is positive.
A smaller satellite allows Eutelsat to place Europe’s Arianespace launch consortium and SpaceX, in competition to launch the satellite. Arianespace reserves the upper berth of its Ariane 5 rocket for heavier satellites, with the lower berth for lighter spacecraft.
For years, Arianespace was the only viable option for the launch of smaller telecommunications satellites heading to geostationary orbit. Then came SpaceX, whose Falcon 9 rocket (now being upgraded) has specialized in lighter telecommunications payloads.
The result is that a satellite with chemical propulsion would have occupied the Ariane 5 upper berth can now be fitted into the less-costly lower berth or aboard the Falcon 9.
Eutelsat’s goal is to bring down the cost of a high-throughput satellite from 4 million euros per gigabit per second (the cost of its Ka-Sat satellite) to 1 million euros per Gbps of throughput. The figure would include the cost of the satellite, its launch, its gateway Earth stations and insurance. Electric propulsion and launcher competition are a start, but Eutelsat is also counting on coming technologies to get costs to the desired level. At 1 million euros per Gbps, satellite broadband would compete with terrestrial transmissions with mass-market appeal.
Eutelsat 172B satellite, now under construction, will be launched aboard an Ariane 5 for more than 30 percent less than what it would have cost in the upper berth.
The total capital cost of placing a telecommunications satellite into geostationary orbit is made up of the satellite’s construction, accounting for 50 percent of the total; 30 percent for the launch vehicle; and the rest reserved for insurance charges and diverse expenses.
A 30-percent reduction in launch costs will thus result in a 10 percent overall savings in the capital investment. Those are direct savings.
There’s more: An electric-propulsion satellite can count in operating for 18 years in orbit, compared to 15 years for a satellite powered by chemical propellant (a 20 percent increase in lifespan). Once in orbit, a satellite costs very little to operate, so a 20 percent life extension translates into a 10 percent overall cost savings when measured in the cost per transponder per year of orbital life (the metric many satellite operators use).