Energy harvesting or energy scavenging is when energy is derived from external sources, captured, and stored for small, wireless autonomous devices, e.g. wearable electronics and wireless sensor networks. The fuel to drive large-scale power generation costs resources (oil, coal, etc.), while, the energy source for energy harvesters is present as ambient background. These energy harvesting devices converting ambient energy into electrical energy have attracted much interest in both the military and commercial sectors.
Pavegen is one of such pioneers in an interesting application of these energy harvesting technologies. They design and develop a floor tile that converts the kinetic energy from footsteps into renewable electricity. The tile slabs generate electricity every time someone walks over them, this electric power generated is then used to run low-voltage applications like street lighting, ad displays, etc. The technology provides people with a visual form of renewable energy that they can directly and physically engage with – with extensive application in high footfall locations such as train stations, entertainment theaters, shopping centers, etc.
- Made from mostly recycled rubber and some marine grade stainless steel, the Pavegen tiles can be retrofitted to existing structures. They are designed to withstand outdoor conditions and use in high foot-traffic areas. The converted kinetic energy can be stored in a lithium polymer battery or used to power low voltage applications (e.g. street lighting, etc). They have multiple installations around the world and new tile developments which they monitor for durability and performance.
- It also sends out wireless data useful for a lot of applications including – crowd flow modeling (for cities, retailers, etc) and other data processing and monitoring capabilities – with more possibilities in the unfolding internet of things. The tiles look like a regular floor tile until you lift the astroturf surface and see the network of circuitry inside. This is part of the pricing obstacle to widespread adoption as the tiles come in at more cost relative to normal flooring. New technology and improvements are expected over time as evident in their new V3 tile system – a sleeker and far more efficient model, generating over 200 times more power than the first model manufactured in 2009. Key global clients of the company include Diageo, Schneider Electric, Ford Motor Company, Adidas, Siemens, Nike and Coca-Cola.
Renewable energy production will account for almost two-thirds of net additions to global power capacity, taking the share of renewable energy in global power generation to over 26% by 2020. Though these energy harvesting technologies like Pavegen are criticized for developing tiny amounts of energy, it’s unique features make it an interesting part of the energy mix for greener smart energy applications of the future.
In general, future applications of energy harvesting technologies may include high power output devices (or arrays of such devices) deployed at remote locations to serve as reliable power stations for large systems. These devices will get sufficiently robust to endure long-term exposure to hostile environments and have a broad range of dynamic sensitivity to exploit an entire spectrum of motion. Some other notworthy companies and products we noted include:
Bionic Power is a privately-held technology company based in Vancouver, British Columbia. Their energy harvesting technology generates substantial electricity during human walking while requiring little extra effort from the user. The energy harvester mounts at the knee and selectively engages power generation at the end of the swing phase, thus assisting deceleration of each knee joint with each stride.
SolePower has a power-generating shoe insole for charging portable electronics like cell phones, music players, or GPS devices. What they do differently, is to build the device into a removable insole so it doesn’t need to be embedded in a shoe. This means you can swap it between your favorite pair of sneakers and your hiking boots. The patented SolePower EnSoles received the 2014 Invention of the Year Award from Popular Science.
Enerbee is an innovative startup resulting from high-level research in energy harvesting. Founded in 2014 and based in Grenoble (France), Enerbee has developed a breakthrough energy harvesting technology able to generate energy from a wide range of movements. The company’s unique value is the ability to deliver fully autonomous products and solutions satisfying today’s IoT needs.