At a breakfast meeting with DC-based defense reporters today, Secretary of the Navy Ray Mabus (now clearly not in contention to be SecDef) sketched a future force of unmanned ships pulling power from the sea floor.
Office of Naval Research just did a patent on making energy with a combination of seawater and organic material at the bottom of the ocean. If this can work in large quantities, you can see an unmanned vehicle out there simply burrowing down into the bottom of the ocean trying to recharge. ... It's unmanned systems [like that] that offer tremendous versatility and tremendous reach.The process gets a little more scientific than I'm capable of explaining comfortably, so I'll let a 2010 news report do it for me. We also invite DT readers who are spooled up on this to explain as well...
These fuel cells convert naturally occurring fuels and oxidants in the marine environment into electricity making them a viable power source for long-term operation of autonomous underwater unmanned vehicles, in-water sensors, and devices used for surveillance and monitoring the ocean environment.While so far the experimentation on this has been essentially charging batteries for buoys or radio monitors, Mabus' vision conjures up images of robotic ships controlling the world of The Matrix. Imagine unmanned nuclear subs that can derive power from the sea floor on their own?...Clearly some down sides to this kind of robotic warfare.
"Think of it as a battery that runs on mud," ONR Program Manager Dr. Linda Chrisey said. "They are sustainable, environmentally friendly and don't involve hazardous reactants like a regular battery might because they use the natural carbon in the marine environment. For example, we are working on a 4-foot long autonomous underwater vehicle that will settle on the seafloor and recharge its batteries using this fuel cell approach. We are already able to power many types of sensors using microbial fuel cells."