Energy Harvesting – The lights may be going out for ZigBee…

Every farmer knows that if they want a good harvest they need to take care where they sow their seed.  One of the first principles they’ll learn is to sow the seeds on their own land, not their neighbours.  So I was somewhat shocked to see the recent announcement from the ZigBee Alliance about their new Energy Harvesting profile, dubbed ZigBee Green Power.  In their press release they talk about a feature set to establish a global, standard technology for self-powered devices operating through energy harvesting techniques.

There’s nothing fundamentally wrong with that as a goal.  Energy harvesting’s a fascinating area of technology, which has only recently emerged from research into reality, as better generating technology is devised, along with lower power radios.  It’s taken around twenty five years to come to fruition, during which companies and researchers have been actively patenting their ideas and techniques.  Those patents don’t just cover the energy harvesting devices, they cover all of the parts of the chain – generating the power, converting it to a form that can be used, storing it, connecting to a radio and transmitting information.  They also cover the applications, such as wireless light switches.

Hence my amazement at the naivety of the ZigBee Green Power press release.  Whether or not ZigBee can come up with a specification that is able to run on a few tens of microJoules of power is irrelevant – I’m sure they can as they’ve bright people working in the specification group.  What is far more important is whether or not it will be legal for anyone to ship a device that is based on it, as it will almost certainly infringe the Intellectual Property of the main stakeholders.  So the press release looks like either an ill thought out, opportunistic attempt to regain some momentum, or a worrying piece of evidence that the ZigBee Alliance has lost the plot…

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