Energy harvesting has endless applications for the planet. Old batteries are used up and thrown away every single day, ending up in the landfills. But what if there was a way to eliminate the need for batteries? What if you could take the energy that comes naturally from the world around you and power your electronics with it? This is where energy harvesting comes in. Here are a few sources from which you can find this energy and how to apply it:

1. Biomechanical Energy Harvesting: Did you know that when you move around, you generate energy? What if you could bottle up all of that energy and power your portable medical devices with it? An energy harvester can be mounted onto your knee and produce substantial electricity, enough to provide power to a prosthetic limb or medical device. The energy that is generated comes from the motion of the joints. The joints producing the most energy are the knees and ankles.
2. Solar Panels: This is a great way that every consumer out there can produce their own clean energy. Solar panels work by absorbing the sunlight to generate electricity. Not only can solar panels be used to power your home or business, but they can also be used to provide refrigeration for medical supplies or to provide power for irrigation. The applications are endless.
3. Piezoelectric Transducers: Put simply, piezo scanners use crystals to convert mechanical energy into electricity. The crystals (such as the one used in a quartz watch or voice recognition software) work as a battery. Applying pressure to the crystals forces the charges out of balance, creating a voltage that can be used to power ultrasound equipment, microphones, and many other devices.
4. Thermoelectric Generators: A device that converts temperature differences into electrical energy work like heat engines. They can be used in automobiles to increase the efficiency of your fuel or to power a plant using waste heat. They are also used on gas pipelines, radio communication, and power generators.

The output of energy harvesting is small, so it will never be able to replace all batteries or other forms of energy that are bad for the environment, but if they could be used hand in hand with micro-machines and nanotechnology, the applications would be unlimited. If you could charge the world's medical devices and ultrasound equipment alone with energy harvesting, how many batteries would you save from ending up in the landfill?