Are the factors in place and aligned for this market to really take off?
It sounds like something for almost nothing, and it is: the apparently "free power" you can get from energy harvesting and scavenging power subsystems. The reality is that cost-effective and effective harvesting is a tough challenge.
But like all new technologies, sometimes getting real traction and success is elusive, and it is not helped by the over-enthusiastic hype of promoters, as in "whatever your problem, 'x' will solve it and make everything wonderful." Still, energy harvesting may be at a point where it has enough of the pieces you need to make it successful where it makes legitimate sense.
I just saw a press release about a report from the Darnell Group (a market research organization) which predicts that such harvesting will cross-over from what they call "introduction" phase into "growth" phase in the 2009/2010 time frame. I'll be honest: I usually don't place much stock in most of these reports, because they usually take a few SWAG (scientific wild-ass guess) survey results and so-called "anecdata" data points, and extrapolate them out several years with the added veneer of meaningless precision ("12.5% growth in 5 years"), all of which is about as ludicrous as you can get when predicting the future.
But this report (no, I won't be buying it, it's $2700) has a much shorter and thus more credible time frame, and I do see enough real-world applications–plus the necessary supporting cast of low-power sensors, interfaces, batteries, and designs, targeting meaningful applications– to say that maybe there is some validity and credibility to this prediction. Check back in a year and we'll see. Until then, what do you think? ⍆