As President Obama pumps billions of dollars from his stimulus package to the cleantech industry, one cannot help but ponder, “Do we have enough ideas to justify the investment?”  Over the years, the Technical Insights’ team at Frost & Sullivan has been tracking emerging technology trends in the cleantech space; and we can say with confidence that there are significant and exciting developments in the area of energy harvesting.

Energy harvesting (EH) is the process of converting energy from ambient sources into electricity to make devices or systems more self-sufficient. Energy harvesting technologies use energy generated from the environment or from humans to enable devices or systems to be powered directly without having to rely on batteries. While energy harvesting devices that convert ambient energy into electrical energy currently do not produce sufficient energy to perform large-scale work, such as replacing power stations with grid electricity from wind or wave power, energy harvesters are finding key opportunities to provide a relatively small amount of power to power, for example, low-energy electronics. Furthermore, energy harvesting techniques have potential to progress from having the opportunity to  provide back-up power to providing longer-term energy for consumer electronics (handheld electronic) products.

Harvesting of ambient or human-powered energy can be performed using varied types of sources, including electromagnetic radiation (solar energy), vibration-based energy-harvesting (e.g., piezoelectric, magnetic induction, electrostatic), thermal energy, and electroactive polymer technology. Moreover, RF (radio frequency) energy harvesting technology has been investigated to, for example, harvest power from a television transmission tower to power a thermometer/hygrometer with an LCD display; harvest the power of an RF reader’s radio signals to sense such quantities as light, temperature, acceleration, strain, level; or to convert RF energy into DC power to power small devices, such as cell phones. Human energy harvesting techniques can include piezoelectric, electromagnetic, thermal, electroactive polymers, biomechanical techniques.

Energy harvesting technology has realistic potential, particularly if the efficiency of EH can be increased and cost of EH reduced, in diverse application areas, such as: low power handheld electronic devices, such a mobile phones, personal digital assistants (PDA’s), portable audio video players and other handheld devices; sensing/communication networks; radio frequency identification (RFID) applications; building automation and technologies; and medical implantable devices.

Key advances occurring in energy harvesting technologies, including, for example, progress in human energy harvesting techniques, such as Bionic Power’s (BC, Canada) wearable knee brace that derives biomechanical energy harvesting  from walking; piezoelectric-based energy harvesting using a backpack.