Energy is everywhere within reach; waiting to be harvested. Today, energy harvesting wireless solutions are well established in the commercial building automation sector. The technology, however, is still in its infancy.
New application fields for batteryless wireless communication will be found to further enhance the world around us, including structural health monitoring (SHM), water quality control, forest fire prevention, smart city management and medical assessment.
This future is not so far off when we look at the ongoing development of energy harvesting wireless solutions and potential future applications.
Based on energy harvesting wireless technology, a wide range of energy-autonomous applications currently exist for connected buildings that use light or temperature differences as their energy source such as batteryless switches, intelligent window handles, temperature, moisture, light sensors, presence detectors, heating valves and smart home systems. However, building automation is by no means where energy-harvesting wireless ends.
Everyone is talking about the Internet of Things, yet how should billings of communicating devices be powered? The answer is by energy harvesting and the reason is simple: Liberating sensors from external power, making them energy-autonomous, opens up unlimited processing and monitoring applications where cables or batteries represent an insurmountable hurdle.
Already, the energy harvesting market is growing and multiplies annually. Forecasts show that this trend will continue, especially as the next generation of energy-harvesting wireless solutions are just around the corner. This includes the development of the following:
Longer distance communication
The next generation of self-powered radio technology will enable radio signal ranges of more than ten times the current range – capable of wirelessly transmitting data via a distance of up to three miles and enabling new applications with high-range requirements outside of the building.
New energy sources
Advanced energy converters that open up new energy sources will enable this long distance radio range. In the near future, we will see new types of mechanical energy harvesters that make use of the energy generated from flowing gases and liquids in particular. For example, metering applications.
New light harvester generations will combine smaller sized solar cells with improved performance. Together with improved energy storage, solar-powered devices will run in complete darkness for several months up to a year.
This potential of harvesting energy from differences in temperature is at the early stage of development. One option is to harvest energy from temperature differences between day and night for outdoor applications.
As energy harvesting wireless technology advances, new application fields will become feasible, including:
Structural health monitoring
Large structures such as bridges, tunnels, dams and drilling platforms must resist extreme forces imposed by weather, earthquakes and traffic. Radio sensors, powered by light, temperature changes and vibration that permanently monitor critical parameters can warn against non-conformance and prevent breakdowns. A similar functionality can provide an alarm notice in the event of an avalanche or rock slide.
Long-range energy-autonomous wireless sensors could be placed over large areas to provide early warnings or monitoring of farm animals and plants to react rapidly to changing conditions. For example, they can be used to prevent the spread of forest fires, or to ensure an optimal supply of water and care for plants.
We only have one planet and all resources need to be protected and sustained. Batteryless sensor networks can support this by providing the data required to monitor water quantity and quality, or the movement of schools of fish. Self-powered detectors can report water, oil and gas leaks.
By 2030, 60% of the population is expected to live in cities, approximately six billion people. Intelligent control will be needed to coordinate daily lives and prevent a city from collapsing into turmoil. This includes automated control of traffic, streetlights, energy supply, the transportation of goods, and also waste disposal. This can only be realized with millions of energy-autonomous sensor nodes collecting and delivering the necessary data.
Another broad application area is in making our lives easier, more secure and comfortable. This includes new solutions for monitoring vital functions, as well as an autonomous and healthy lifestyle. There are already bracelet prototypes that can monitor functions by using the body’s heat as a source of energy to transmit data wirelessly.
These are just a few areas where batteryless wireless communication continues to develop. It’s easy to imagine hundreds of additional scenarios where energy harvesting wireless solutions will make lives easier.
Laurent Giai-Miniet has been CEO of EnOcean since October 2011. Before joining EnOcean he spent 20 years with Texas Instruments (TI), where he held several management positions. Most recently he was General Manager for Low Power RF Products (LPRF), based in Oslo, Norway. He holds a Masters of Business Administration from the Institut d’Administration des Entreprises IAE (Aix-en-Provence, France). This blog has also been published on Embedded.com’s sister publication, EDN Magazine.