What you have next is the official report of the EnOcean Coalition, ” The Connected Home;Smart Home with Batteryless Wireless Technology”, the first part of which deals with smart home and its wireless technology. The BACpress site is ready.
“Homes will become more intelligent“, “everything can be controlled with one device“ or “one doesn’t need to do anything anymore“. These are typical answers to the question: “What do you have in mind exactly, when you imagine a Smart Home?“. As you can see through these statements, most citizens already have a preconceived idea for the term “Smart Home”. There is no doubt though that the topic is gaining awareness in public, and for many private individuals, owning a Smart Home is fact, not fiction.
There are already numerous pioneers who have successfully converted their origi-nal home into an intelligent one. This is by no means a temporary trend for a few skilled technicians, as current studies show. 58% of all Germans would install an intelligent home automation system during construction, 69% would retrofit one during renovation. Industry experts also expect signifi-cant growth in the coming years: the German Smart Home market value alone is expected to rise to 19 Billion Euros by 2025. This statement is underlined by survey results concerning the appeal of Smart Homes from the customers’ view. 66% of the 500 surveyed find the offer attractive or even very attractive. This results in an addressable market of nearly 20 million households in Germany alone.
What is a Smart Home?
Generally, the term “Smart Home” defines the building automation in a private home, in which single components (sensors and actuators) are networked together in order to form an intelligent system. This forms the technological foundation for an automated control as well as for the compre-hensive operating options of the home automation. For an optimal operation, it is necessary to gath-er extensive data. For example, during heating, the current temperature of every room is an essential figure for the individual room control.
This connection between single components combined with intelligent control increases comfort, saves energy and ensures more safety in the house. Control can be exerted either over stationary control panels or over mobile devices such as smartphones or tablets. At the same time, the user is also able to change settings through more clas-sical means, for instance light switches, or through a remote control.
Networking different home automation disciplines enables a comprehensive spectrum of possible applications for intelligent control in various private building sectors. The most important are:
A Smart Home’s system technology is comparable to a modern car’s. There too, copious sensors col-lect different data nowadays. These are processed in order to subsequently lower fuel consumption, offer passengers more safety, and enhance relaxation whilst driving. The demands placed on the building automation system are similarly complex.
On the one hand, the client wants to be able to install his system quickly and easily, and be able to expand it at any time. On the other hand, all com-ponents made by different manufacturers must be able to seamlessly work together in one system. This is the only way to centrally control and operate them over a singular user interface. In order to guarantee high functional safety, all single components must be able to communicate decentralized with each other.
New Possibilities due to Wireless
The normative, basic ideas for the Smart Home system are not new, by any means. In modern office design especially, techniques which save energy and increase work space comfort are well estab-lished. Current technological progress, which simplifies installation and operation, now enables the networking and automation of private households. One central aspect here is wireless technology. During the networking of single components, radio based solutions offer clear advantages: cabling and the resulting mounting in the installation phase is dropped. Furthermore, costs for cable line are reduced. The cost advantage during redevelopment lies up to 70% compared to wired solutions. And the costs saved using wireless solutions for new constructions are at 15%. Moreover, the user remains completely flexible even after the installation. Sensors or feelers are supplemented or moved without a problem.
Not only the residents profit from these completely new possibilities. Planners and architects too profit from this newly won flexibility. Thanks to wireless technology, switches can now even be placed on thin or glass partition walls. Strong impulses are now also com-ing from new media carriers. More and more electronic entertainment devices, such as televisions or hi-fi systems, are equipped with wireless interfaces and thus can be easily networked with other wireless applications.
Energy Harvesting Wireless Technology
The batteryless wireless technology from EnOcean has a special position in the market. The compo-nents equipped with this technology not only work wireless but batteryless too. Due to Energy Har-vesting, the wireless modules gain their energy from the environment, for example from motion, light or temperature differences. Instead of batteries, mini solar cells, electro-mechanic and thermal energy converters provide the energy needed. Through this self-sufficient operation, any mainte-nance usually needed with similar, battery-driven solutions, is no longer necessary.
The radio trans-mission used has very low energy demand while simultaneously offering a large range. Outdoors, this range is about 300 meters, in buildings it lies at up to 30 meters. One reason for the low energy con-sumption is the short transmission period. Within just 1 millisecond (ms), the complete transmission-/reception process occurs. Not only does this save energy, the chance of collision between different telegrams is lowered. Two repeat-telegrams are sent within 30 ms in order to prevent erroneous transmissions.
Batteryless wireless technology combines the respective advantages of both wired and wireless sys-tems: it works maintenance-free, guarantees reliable operation and is flexible and cheap to install.
The benefits of EnOcean wireless technology at a glance:
- Reduced installation costs in comparison to wired Bus systems covering the same functionalities:
- 15% cost savings in new constructions1
- 70% cost savings in retrofits1
- Flexible positioning of sensors, even after installation
- Maintenance-free, no batteries
- Optimized measurements due to flexible positioning of sensors
- Variety of products of an established eco-system (EnOcean Alliance)
- Product interoperability
- International ISO/IEC standard (ISO/IEC 14543-3-10)
- Large number of successful projects worldwide
Secure Data Transmission
In a Smart Home sensors and actuators send and receive different values and information. The secu-rity and reliability of the data plays an important role. EnOcean-radio already offers basic functions for a secure two-way communication in the home automation. Every data packet includes a check-sum, which ensures the integrity of the telegram and thus avoids transmission errors. Also, every module possesses a unique 32 bit long identification number, in order to avoid telegram overlaps and to authenticate sensor identities. Further methods are based on these basic security features.
As a permanently self changing security mechanism, every telegram is created with a rolling code. The current rolling code forms the basis in order to generate an authentication code. The receiving sys-tem can validate the data packet with help from the rolling code and protects itself from repeat at-tacks. A further measure is the encryption of the data packets through the transmitter. A high en-cryption protection is offered by the AES-algorithm with 128 bit-keys, which is also used for car key wireless.
The safety functions offer high protection for data traffic in a networked home and can be adapted to the receptive requirements. This makes it possible to connect EnOcean wireless technology with security relevant applications such as door lock switches. An important point regarding a useful and cost-effective solution is the appropriate adjustment of the security level for each respective applica-tion, as higher security means higher energy demands for the transmission and calculation of the telegrams.
Less Electro Smog than with Conventional Switches
An investigation by the independent ECOLOG institute has shown that the high frequency fields produced by batteryless wireless technology are a hundred times less powerful than classical,wired solutions. Additionally, the devices, in contrast to other wireless standards such as WiFi, only transmit for a few milliseconds, and only when an activity is necessary. As a result, even radio-sensitive people can use building radio systems without a problem. Furthermore, the products don’t create any low-frequency electro-magnetic emissions.
Encrypted Data Transmission
The safety of data is the highest priority, especially in regard of the requirements of a networked home. Unwanted intrusions into privacy, data interception or losing control of the system are the main concerns. Therefore, an intelligent networking in the building requires further security levels for wireless systems.
One central protective measure against the abuse of a radio system is the encryption of data. This also applies for Smart Homes. The data is encrypted by each transmitter individually and then de-crypted by the respective receiver. Batteryless wireless technology uses an ever self-changing securi-ty mechanism, for example a 16-bit or 24-bit-long Rolling Code (RC), which is incremented with every telegram.
Telegram header, telegram data and the current Rolling Code in turn form the basis, in order to generate a 24- or 32-bit-long number-based authentication code (Cypher-based Message Authentication Code, CMAC). The CMAC is likewise protected through a 128-AES-encryption algo-rithm. Based on the code, the receiver system can conclusively verify a data packet. This functionality protects networks, especially from repeat attacks, so called Replay Attacks. Another mechanism is the encryption of data packets through the transmitter. The data is encrypted by the AES-algorithm with a 128-bit key. That way, eavesdropping is prevented.
Broad Product Range
EnOcean wireless is internationally standardized as ISO/IEC 14543-3-10. This standard is optimized for radio solutions with particularly low energy consumption and Energy Harvesting. Together with application profiles (EnOcean Equipment Profiles) from the EnOcean Alliance, the prerequisites for a completely interoperable and open radio technology, comparable with Bluetooth or WiFi, are given. In this way, products from diverse manufacturers can work together in one system without a prob-lem. In Europe, batteryless wireless technology uses the frequency channel 868 MHz, which is only approved for pulse signals.
EnOcean exclusively offers its batteryless wireless technology to product manufacturers (OEMs), which then integrate it into their solutions. These partners are organized in the EnOcean Alliance, an independent initiative with over 350 members, who have already successfully brought more than 1,200 interoperable products into the market. The offer covers batteryless switches, intelligent window handles, temperature-, humidity-, or light sensors, presence detectors, as well as actuators, gateways, and switchboards, along with complete Smart Home systems. Since 2013, radiator valve attachments are also offered, which use the temperature differences present at radiators, in order to power communication and changes in stroke.