Piezoelectric Generators

Nicholas writes:

I just wanted to put the idea forward of piezoelectric generators.  As I read an article on them a little while ago about some Israeli engineers testing them on a stretch of highway. They spoke about storing some of the electricity generated from this system so electric cars can recharge on the side of the road, or maybe you could say recharging stations instead of petrol/fuel stations. I’m not sure on your views on this source of energy but from what I have read piezoelectric generators are not just limited to roadways they can be used on railway lines, airport runways and all high traffic areas even sidewalks, shopping malls, airport terminals, sporting arenas the list seems endless. Anyway I would really value your opinion on piezoelectric generators if you could find the time to reply.

Hi, Nicholas.  I haven’t read too much about this, although I did see an article on the work in Israel (linked above).  When you need a small amount of energy for a certain purpose, e.g., igniting a gas lighter for your fireplace or barbecue, piezoelectricity is marvelous.  But it’s extremely expensive and inefficient, given the scale of the concepts at hand, for instance, recapturing a tiny percentage of the waste-energy that comes from driving (or walking, or whatever). 

When we think about the magnitude of the impending energy crisis, one that comes from a population that is in the process of quintupling in size from 1950 – 2050, and, at the same time, is experiencing its energy consumption per capita going through the roof, we shouldn’t get too excited about concepts like these.  I see huge expense and little potential to “move the needle” in terms of the world’s energy picture.  In contrast, improving CAFE (fuel efficiency) standards or reducing VMT (vehicle miles traveled) even infinitesimally would have a far greater effect – and all without re-doing our roadways.  

If we’re going to address this crisis, it will be through significant efforts to reduce consumption via efficiency and conservation, as well as renewable energy solutions on a major scale. 

If anyone disagrees with me, please speak up.