With heaters, pumps, satellite communications, and instruments the O-buoy has a considerable appetite for power. This appetite is regulated by sophisticated control processes to effectively manage power use. The core of the power system is three lithium battery packs. Each pack (see right) is is constructed of 50 battery strings connected in parallel, weighing 21 kg, with a circuit voltage of 15 volts and a current capacity of 460 Amp-hours. A string consists of five primary lithium-sulfur dioxide D-size cells batteries connected in series. Each string is protected against over current and temperature surges with the use of polyswitch resettable devices. Isolation between strings is provided by a Schottky diode. The entire battery pack is protected with a single polyswitch resettable device to guard against over current and temperature surges.The O-Buoy uses three lithium battery packs connected in parallel to have a total capacity of 1380 Amp-hrs.
External to the O-Buoy is a solar charged lead acid battery bank. The battery bank is used to supplement the Lithium battery pack during times of sufficient solar incident irradiance. The external battery bank consists of four high Amp-hr capacity lead acid batteries connected in parallel. Diode isolation is provided to protect against battery failure. Four ASE 50 watt solar panels and two Morningstar solar charge controller are used to charge the battery bank. Connected to each solar charge controller are two solar panels capable of producing 100 watts under ideal conditions. The pair of charge controllers is connected in parallel to the battery array. Connectors on the mast of the O-Buoy permit connection of the external battery array.