The word UAV brings to our mind unmanned aerial vehicles flying high above the battlefields of Iraq and Afghanistan, tracking down and bombing militant hideouts. UAVs have evolved from being war machines to tools to study the environment or carry out reconnaissance in a clean green way. So, we put together a list of the cleanest, greenest UAVs flying or all set to fly the earth’s skies.
HADA Electric UAV
Engineers at Spain’s National Institute of Aerospace Technology have put this electric UAV called the HADA together. This UAV combines the of agility and go-anywhere capability of a helicopter with the long distance flight capability of an airplane to end up with a hybrid combining the best of both worlds. All this while consuming only one-third of the amount of fuel normally consumed by conventional aircraft as the HADA UAV is powered by electricity.
Northrop Grumman RQ-4 UAV
The USAF is more known for it’s propensity to bomb and weed out enemies of America. In a major departure from the norm, the USAF has handed over a couple of Northrop Grumman RQ-4 UAVs to NASA. Far from bombing and spying, these UAVs will actually verify the measurements of atmospheric gases that are recorded by its AURA satellite that continuously monitors the planet. Now, that is a perfect example of military tech being used for the greater good.
Korea Aerospace University’s solar-powered UAV
Researchers at the Korean Aerospace University and Korea Institute of science and technology have gotten together to build a zero emission UAV. To do this, the 40m UAV will use an array of solar panels on it’s airframe. The solar panels will generate power and charge the lithium ion batteries to propel the drone’s electric motor for months together. By 2012, the researchers hope to serialize production of the zero emission UAV.
Reconnaissance or spying costs a lot of money, more so if it is done aerially. To help governments save millions of dollars, a bunch of researchers at Australia’s Queensland University of Technology have put a solar powered UAV together. Dubbed the Green Falcon, this UAV will use solar power to propel itself. The Green Falcon, which has a wingspan of 2.5m and is designed mainly for peaceful purposes like surveillance of bush fires in the outback and for environmental research.
Aurora’s Solar UAV
Five full years. That is the time for which Aurora Flight Sciences’ UAV can fly continuously. If you’re wondering how this UAV can manage to fly for so long, it can do so as it powered by an inexhaustible source of power, the sun. This solar powered UAV will charge its batteries while flying around in the daytime. The recharged batteries will power the UAV at night when it’s cruising speed also will decrease from 63 m/s to 43 m/s. This solar powered UAV has been developed by Aurora Flight Sciences as a part of DARPA’s Vulture Program.
Silent Sentinel Hybrid UAV
The Silent Sentinel Hybrid UAV is a multipurpose unmanned aerial vehicle developed by Bye Aerospace and Ascent Solar Technologies. This solar powered UAV harnesses solar energy through its wing-mounted photovoltaic cells. The harnessed solar power will be stored in lithium ion batteries which will provide juice to power the UAV to fly. While solar energy is its secondary source of power, the primary source of the Silent Sentinel UAV will be the stored power in the lithium ion batteries. The Silent Sentinel can also be deployed for other purposes like environment monitoring apart from it’s primary purpose of military surveillance.
Fuel Cell Powered UAV
Hydrogen power comes calling on UAVs. Students at Georgia Tech have designed this UAV that flies with hydrogen power. This UAV which has a 22-foot wingspan uses a proton exchange membrane (PEM) fuel cell using compressed hydrogen. This makes it a very unique zero emission UAV that uses a next generation fuel-like hydrogen for propulsion.
Ion Tiger UAV
While hydrogen fuel cell powered UAVs aren’t new, a fuel cell powered UAV that flies for almost a full day just on hydrogen power certainly is. Scientists at the Naval Research Laboratory have developed a UAV called the Ion Tiger, one which can fly for almost a full day while being powered by a 550W fuel cell. This makes the Ion Tiger a perfect compromise between range and zero emission capability. The Ion Tiger has even set a endurance record by continuously flying for 23 hours and 17 minutes.
Coaxial UAV Helicopter
Unmanned helicopters are still a novelty in the world of UAVs. More so, if they happen to be powered by a hybrid system. Here is one such helicopter UAV that uses power from a bank of batteries for propulsion. Falx Air’s Helicopter UAV uses two sets of three high torque motors, which are mounted along the length of the main shaft. The UAV generates electricity by using a small rotary engine that drives a permanent magnet generator. If the generator fails, the UAV helicopter can safely head back to its base by the power stored in the batteries.
Drone powered by Solar Panels
The US Army is funding a group of researchers at the University of Washington to develop a drone that can be powered by microorganisms, well almost. The researchers are replicating the process of generating energy in the same way that the micro-organisms do. For this the researchers are developing a synthetic dye that will mimic the process of producing energy. This dye will then be used in the wings of the UAV, thus generating power to propel it. So far, the USAF has spent almost $450,000 on this project and expects a production-ready drone by 2012.