All of the spacecraft's power is generated, stored and
distributed by the electrical power subsystem. The system
obtains its power from an array of standard silicon
solar cells arranged on two panels on either side of
the equipment deck. The two solar panel wings, made
of silicon and aluminum, are fixed in place. They hold
grids of silicon cells which generate 265 watts at Earth's
distance from the Sun. A power distribution and drive
unit contains switches that send power to various loads
around the spacecraft. Power is also stored in a 16-amp-hour
nickel hydrogen battery.
The electrical system also contains a pyro initiator
unit which fires small explosive devices that configure
the spacecraft following launch, performing such tasks
as extending Genesis' solar array and opening covers
on science instruments. The pyrotechnic system also
releases the sample return capsule by actuating cable
cutters to allow the heat shield and back shell to separate
from the spacecraft's body.
The electrical power subsystem weighs 36.5 kilograms
(80.5 pounds).
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