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Off Grid Energy Independence
Posted on February 25, 2010 by  & 

An interview with EnOcean

EnOcean is the largest supplier of energy harvesting powered wireless sensors. Its products have been deployed in more than 100,000 buildings around the World and it has sold millions of sensors, switches are other components. EnOcean technology is currently incorporated in around 500 products, which are installed by system integrators and channel partners many of whom are members of the "EnOcean Alliance", which now has 140 participating organizations. The EnOcean Alliance is currently formally standardizing the energy harvesting wireless technology to ensure multi-vendor product interoperability and has recently released the first version of the international standard.
IDTechEx CEO Raghu Das recently interviewed Graham Martin, the Chairman and CEO of EnOcean Alliance.
EnOcean, with approximately 60 employees now, was spun out of Siemens, who still hold close to 20% in the company. Siemens had conducted a significant amount of research on energy harvesting wireless sensors in the 1990's, and filed a range of core patents at that time. These were all transferred to EnOcean, and today the company has dozens of patents granted in this field.


Today, about 90% of EnOcean's products are used in buildings to reduce cost, automate, reduce manual labour, increase comfort and flexibility, provider greater energy efficiency and reduce CO2 output. The most popular products to date are mechanical light switches, which incorporate a mechanical electrodynamic harvester. As the switch is pressed, the mechanical energy asserted powers a wireless signal. A module is attached to the light fitting and it turns the light on, off or dims according to the signal detected. The light fitting can also incorporate sensors which monitor if people have left the room and it automatically turns off the light. This saves cabling, the cost of plastering and decorating, and wasted energy. The majority of energy cost savings are achieved in HVAC (heating, ventilation, air-conditioning) systems using signals from solar or mechanical powered sensors providing information about occupancy, temperature, humidity, window & door status etc. to reduce or switch off heating or cooling automatically when not required.
The technology has been adopted in schools, hotels, hospitals, offices, industrial buildings and other buildings. Martin reported that in such buildings the return on investment on energy savings alone is about two years, and in some cases as short as 8 months (particularly hotels, where frequently lights or TVs are left on or the heating / cooling is running full blast when the rooms are unoccupied or when windows or balcony doors are open). The energy saved is typically 20-30%. The technology is also used in residential properties but because people pay personally for the electricity the energy saving is lower because people are more careful. However, the system is much more flexible than wired systems because it does not require wiring to be embedded into the wall and the decoration repaired, so when this is factored in the savings can be rapid. The cost of the light switch depends upon quantities and wall plates choice, can be around $50 in higher volumes.

EnOcean Products

Historically speaking, around two thirds of the products deployed incorporate a mechanical electrodynamic energy harvester, which EnOcean developed. About a third of their products have used other energy harvesters - mainly solar cells, but some thermal energy harvesters and now available. OEM products include light switches, motion detectors, thermostats, window contacts and there is constant extension to the range. Martin explained that the new EnOcean technology based mouse traps have been very popular. The mouse going into the trap releases a mechanical object whose motion powers a wireless signal. The operator then knows when and where a mouse is caught rather than having to manually check every trap on a regular basis. The animal is trapped rather than killed and can be released outside, reducing the risk of disease.
The technology has also been used in cold chain management supply chains - monitoring, for example, frozen foods, using solar powered temperature and humidity sensors. In industry switches and sensors are used in automotive production lines. In trains wireless sensor modules are placed in seats to monitor utilization so operators know if they need to increase or decrease the number of carriages on the train.


The electrodynamic mechanical energy harvester EnOcean used was qualified for at least 50,000 clicks, which at an average of 5 uses per day gives it an operating life of about 30 years. Now newer versions double the qualified lifetime to 100,000 clicks. EnOcean did also intensively research piezo electrics, introducing products to the market in 2002, but dropped production of products around five years ago, because mechanical wear on the device caused it to deteriorate and it would only last reliably half as long as the electrodynamic version. The voltage output was also not as stable as the electrodynamic version. The company sought a technology that was highly reliable and could be economically mass produced in millions, and settled on electrodynamic harvesters as the most reliable mechanical energy harvesting technology.


Martin reported that many developers are not looking closely into the patent situation. EnOcean own some core patents covering aspects of using energy harvesters in wireless sensors to harvest, store, and wirelessly send data, which are protected worldwide. Many companies are working on this topic but have yet to study the IP situation more closely.


EnOcean was founded in Germany and has historically focussed its activities in Europe. As a result, Europe accounts for more than 50% of its business. A few years ago the company began selling in the US and last year saw growth of 400% there compared to the year before. EnOcean has now started to also sell in Asia. Martin explained that they usually see a correlation between territories that are more energy conscious and interest in their products. Over the last few years countries such as the US and UK have become large growth sectors. When asked if end user customers are educated well enough about the technology, Martin estimated that about 50% of potential users in Germany are aware of energy efficient technologies for buildings, in the UK it is probably less than 10%, but growing rapidly. EnOcean does not release its annual sales figures but Martin confirmed it is an 8 figure US dollar amount.
For more information EnOcean are presenting and exhibiting at the IDTechEx Energy Harvesting & Storage event in Munich, Germany on May 26-27 2010. For more information see The event includes a tour to EnOcean's facilities.
Top image of Graham Martin source EnOcean Alliance

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Posted on: February 25, 2010

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