Energy Harvesting & Storage and RTLS & WSN conference summary
The first day of this IDTechEx conference in Denver Colorado on November 3-4 (attended by more than 290 attendees) was focused on presentations from end users of energy harvesting and wireless sensor networks technologies, with the first presentation given by IDTechEx CEO Raghu Das, giving an overview of needs for energy harvesting as well as the three generations of technologies (active RFID, RTLS and mesh & WSN) that have evolved into the current market for Wireless Sensor Networks, a market due to reach US$1.75 Billion by 2019.
Bob Karschnia of Emerson focused on the process control implementations of the company on dangerous environments such as oil rigs, chemical plants, etc. Emerson's solution, wirelessHART, implemented by in about 1000 locations in the last two years, where reliability is crucial and mistakes cost dearly, leads to increased safety, environmentally conscious practices, helps attain competitive advantage and increase efficiencies even under skilled labour shortage regimes. According to Mr Karschnia sensor power is key for the ubiquity of WSN: Achieving higher energy densities without the accompanying exponential rise in costs will lead to higher degree of adoption.
EH technologies adopted are mainly solar for outdoors applications, followed by vibration or thermal harvesting later on, mainly for indoor applications.
Dr Richard Waters focused on kinetic energy harvesting developments at SPAWAR, a DoD centre of excellence. Using Faraday's law and high spatial magnetic field gradients, power can be generated even for very small coil displacements. Dr Waters described how changing coil diameter leads to optimized power output, bandwidth dependence on coil acceleration and how for different sizes of the devices, different power outputs can be achieved, in order to satisfy varying needs in different applications.
Inna Kozinsky of Bosch described the €46.3 Billion company's energy harvesting needs. Looking into different environments, she described the level of power at which energy harvesters become useful (~50mW with some consumer goods applications having requirements up to 2500mW), and how design optimization may bring the value down in the future down to ~3mW. What can be currently harvested in automotive applications for example, ranges from 3mW/g (no suspension environment) up to 30mW/g (suspension present), with thermoelectric harvesting at specific parts of the engine reaching potentially 2W/cm2.
Oliver Schneider described implementations at the architecture/ R&D firm the Facility: Innovate. The company mainly works with footfall and vibration harvesting, having been commissioned to create an energy harvesting staircase at a transport gateway for the 2012 Olympic Games in London, that would harvest energy from the footfall of the some 22,000 per day passing through. Electromagnetic induction is the preferred technology there, rather than piezoelectric energy harvesting, mainly for reasons of reliability according to Mr. Schneider.
Curt Smith at the CTO office of BP described their "game changer" Keeping Track technology , while Stacey Burr from Adidas focused on the integration of sensors and energy harvesting into wearable textile electronics, pointing out how they should be low cost (as conventional textile technologies are), lightweight, durable and flexible. Examples include warming fabrics, illuminating fabrics for safety or even fabrics with touch control functionalities. A major focus of Adidas is wearable health and body monitoring, sensing skin, core body temperature, heart rate etc. This approach leads to the concept of the "Rise of the Virtual Trainer" according to Ms Burr, with challenges lying within the satisfaction of power demands for these electronics and achieving lifetimes of 6-18 months or equivalently 100 washes/wears.
Oriane Gatine of the SNCF in France focused on energy harvesting issues for trains, describing how important it is to realize the wide variety of environments (outdoors: leaf coverage or equipment theft, electric arcs at catenaries, indoors: radio frequency or wifi systems interference inside a train station) an EH device would see, highlighting once more the need for reliability of technologies deployed.
Finally in the keynote sessions, Joe Keating focused on energy storage and Infinite Power Solutions' INFINERGY Micro Power Module, which was launched officially on Monday the 2nd of November. This solutions, that integrates input of varying energy harvesting sources, power management and storage comes in 2 varieties, both are small and thin and can be quickly recharged (30 minutes for a full recharge when connected to a solar cell).
Other presentations on the first day included Jim Vogeley of Adaptive Energy, winner of an IDTechEx award later on that evening at the Awards dinner for their joule-thief™ energy harvester, Jerry Ruddle of Advanced Cerametrics who described the companies spun ceramic fibres, light, flexible and embedded in a matrix to form a high-power delivering "piezo fibre composite".
NASA presented on their use of thermoelectric energy harvesters to power the next Mars rover. Conventional planetry exploration vehicles are solar powered, but when it is dark they cannot operate. The thermally operated vehicle can still work in the dark.
Lockheed Martin gave a wide range of examples of their energy harvesting, inviting the audience to approach them if anyone could provide suitable solutions. The company, one of the largest military contractors, seeks high quality, reliable energy harvesters and are willing to pay high prices.
Robert Kowalik of Mojix closed the first day of the event with the description of the company's STAR system, working on extending the accuracy and reach of passive RFID.
Further details from this IDTechEx event will be covered in Energy Harvesting Journal.