Monday, June 22, 2015

Zigbee Pro feat Green Power: Solution for Lower Energy of Zigbee and Energy Harvesting



In previous post, I have posted about general standard of Zigbee technology which mostly related to functionality of each standard with respect to OSI layer. Some of them are defined by IEEE 802.15.4 and the rest are works from Zigbee Alliance. Further possibility of Zigbee implementation to be more powerful in term of energy usage is by deploying energy harvesting into Zigbee. Zigbee has already had low energy consumption and how long we have to wait until it is capable to be independence device combined with energy harvesting technology?

Zigbee Pro 2012 Feature Green Power has been released by Zigbee Alliance to accommodate this possibility. It seems that Zigbee Alliance pretty aware in exploiting on Zigbee's potential. It is trying to keep pushing Zigbee capabilities to achieve excellent performance, not only in term of communication system but also energy usage. It can be one way to compete with other technologies in the market too. 

Using Green Power, Zigbee Alliance aims to provide energy efficient or even battery-less Zigbee device with easy installation and less maintenance. Zigbee has widely known as low energy consumption but with this feature the energy consumption can be reduced 100 times compared to normal Zigbee. That is why, deployment of energy harvesting is getting more feasible. Zigbee Alliance has demonstrated that controlling the light switch can be done by obtaining energy only from the flipping of the switch.

Surely, there are more variety of energy harvesting can be deployed into Zigbee Pro with Green Power. Two types of energy harvesting: bursting and trickling energy harvesting can be facilitated by Green Power. Trickling energy harvesting create sufficient energy continuously over long period such as solar cell. Meanwhile, bursting energy harvesting generate pretty much energy in short time such as piezo-electric, dynamo/electro-mechanics or vibrators. Any types of the harvesters will not be a problem for Green Power.

In fact, using Green Power is not always taking out the batteries totally from the Zigbee. It is really good to have independent devices such that reducing the maintenance tasks and cost. But, deploying Green Power device with batteries as main power is still possible. Perhaps, using batteries cost much lower choice rather than implementing energy harvester. Or there may be circumstances that do not support energy harvesting scenario for example in the absence of light or motion as source of energy. This way, it may not make use of energy harvesting, but low energy consumption from the device will reduce significantly and prolong the lifetime of the batteries.

It is also possible to insert Zigbee device equipped with Green Power into existing network. It is not necessary to make any configuration as long as existing network implements Zigbee Pro 2012. This is another advantage of Green Power. Zigbee devices equipped with Green Power can directly use the existing network and utilize the network to perform as ordinary network. Routing procedure can be used on this network even though not all of the nodes equipped with Green Power just like in the normal way. As for security procedure, Green Power has the same with Zigbee Pro 2012 as well. Thus,  it is very convenient inserting new device due to this interoperability.

In conclusion, Green Power standard released by Zigbee Alliance is one of good milestone in evolution of Zigbee. It can provide very much low power consumption compared to prior technology. It is also prepared for the trend of energy harvesting which may become trend in the future.  Interoperability of Green Power into Zigbee 2012 is also a good feature provided by Green Power.


References:
New ZigBee PRO Feature: Green Power-Connecting Battery-Free Devices.  Zigbee White Paper. 2012
Introducing ZigBee PRO’s new eco-friendly Green Power feature. Webinar documentation. 2013