If Buildings Could Harvest Electricity
Could a smart building be smart enough to transform the motion that takes place inside it, into electricity? I’m Jim Metzner and this is the Pulse of the Planet.
Tarazaga: The piezo ceramic is a ceramic that has the properties of producing voltage out of it when it is strained, when it is compressed or extended.
Ambience: [Voltage being applied to piezo material, vibrating] Rhythmic Clicks
We’re with Mechanical Engineer Pablo Tarazaga, listening to the sound of a piezo ceramic, made from a kind of crystal, that’s turning electricity into motion. But it also has the ability to do the opposite. Pablo and his team a trying to see if it’s possible to turn the typical vibrations of a building like footsteps, into electricity.
Tarazaga: So, because the vibrations are oscillations, they would strain this piece of ceramic back and forth. So the system would produce, basically, an AC voltage output. So, then, what we do is we rectify that, and we connect it to a capacitor, and basically, what we do is we’re charging a battery.So, over months, what we do is we charge this battery due to the normal activities of the building, whether it’s vibration from an earthquake or traffic around the building or people walking next to these smart materials. What they do is they eventually harvest enough energy that they charge a battery, and once this battery’s charged, there’s a lot we can do with that battery.
Tarazaga: Usually, we are at the level of microwatts. So, it’s a very small amount of energy that we can gather, but the idea is that we would use this gathered energy to, say, power a sensor that’s not necessarily accessible. So, maybe there’s a sensor inside the HVAC system, and we don’t want to run a wire to it and we also don’t want to have to change the batteries consistently in an awkward location. So, the idea of energy harvesting fits in certain areas; it doesn’t fit in others.
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