Hi, this is Steven Cherry for IEEE Spectrum’s “Techwise Conversations.”
How many people have lain awake at night listening to the sound of rain? We know the answer to that: It’s about 12 billion, because half the people who have ever lived are alive today [Note: this is incorrect, as a commenter notes below], and probably every single one of them has done so. How many people have had the thought that maybe there’s some useful energy going to waste there? We don’t know the answer to that one, but probably a pretty tiny fraction. How many people have actually harvested that energy?
Just one. We know because he built it and then entered it into the Google Science Fair, where he reached the regional finals, one of four Canadian entries to make it that far.
My guest today is Raymond Wang, a 14-year-old student at the St. George’s School in British Columbia. He came up with a sophisticated yet simple energy collector he calls the “weather harvester” that takes the energy of falling precipitation or wind, turns it into electricity, and stores it on a capacitor. He joins us by phone from Vancouver.
Raymond, welcome to the podcast.
Raymond Wang: Thank you for having me.
Steven Cherry: Raymond, you weren’t one of the 15 finalists—the winner is going to be announced on the 23rd of July—but I’ve looked at the descriptions, and I have to say I think you have the best project. So take us through this. You were listening to the rain at night, lying in bed—what exactly ran through your mind?
Raymond Wang: So, one night when I was lying in bed I heard the sound of rain falling on my roof, and I thought, “Wait a moment; this happened outdoors, and clearly I’m indoors listening to this sound.” Well, since I could hear the sound of rain impacting the roof indoors, I thought, “Hey, that must be a potential source of energy that could be collected.” And so, having recently thought about piezoelectric materials in an article, I thought, “Hey, why not incorporate this into a usable device that can help collect this energy to help power the home?”
Steven Cherry: Do you think a lot of 14-year-olds happen to be reading about piezoelectric materials?
Raymond Wang: Well, I guess it depends on your interests. I just happened to have come across it and was thinking about a science fair idea back then, so that’s how I got into doing this project.
Steven Cherry: So you already had the Google Science Fair in mind already?
Raymond Wang: Yes. I actually got the inspiration from going to science fairs way back in grade three, when one of the students that were in grade seven at that time went to the Canada-wide science fair. And back then I thought [that] when I get to the senior grades, I wanted to do a project like that. And so I began brainstorming things a long time ago, and things like the Google Science Fair—and I was really eager to enter a project into it.
Steven Cherry: So a lot of people have a great idea. I have, on average, 1.2 great ideas every time I take a shower. Then you have to actually do something with them. So, what did you do next?
Raymond Wang: Well, so basically I compared the piezoelectric materials. There’s different ones you could use, like crystal—piezoelectric crystals—there’s piezoelectric polymers, piezoceramics. And so I took the time and compared all of them—well, the most popular ones. And then I thought, what was I looking for? I needed something to be very sensitive in order to collect the energy of things like wind and rain, and so I settled on this one material. And I bought a size that’s roughly the size of [a] sheet of paper, and I placed that on a model house, and I hooked it up to a harvesting circuitry that I made. And basically with that, the mechanical energy of precipitation and wind can be converted into electricity and can be effectively collected and stored for use by a load. I did use polyvinylidene fluoride, or PVDF, and that’s actually part of the initial phase of my research. And later on, after doing the initial experiments to see if the idea works or not, which indeed it did, I went further. And I’m just now trying to develop the materials to make it more efficient, and so perhaps looking at different materials, perhaps having a composite material. And that’s just something I’ve been doing to improve the efficiency of my design.
Steven Cherry: Yeah. I guess it’s pretty hard to measure that in some cases, the key to energy efficiency; I guess there’s a lot of different ways to measure it. One is cost per kilowatt-hour. Coal is less than a penny per kWh, for example; oil is about a nickel; solar is way up there at maybe 40 cents per kWh. I’m sure you can’t have any idea about your system because there’s a bunch of unknowns, including the life span of the system. But do you have any sense yet if this can be made into something practical?
Raymond Wang: Well, what I did with one of my experiments was I placed the weather harvester model that I made into real-life weather conditions—so, conditions such as wind at varying speeds, rain, snow, as well as hail. And I tested the amount of time it took for the circuit to collect a certain amount of energy, and we looked at some favorable numbers over here, and basically we know that the device is feasible. And when I connected an LED bulb after, it powered that for quite a long time.
Steven Cherry: That’s terrific. So you were able to directly use the energy. You were able to store it as well?
Raymond Wang: Yes. I had with my initial models a capacitor to store that electricity.
Steven Cherry: Do you think that it could work with a fuel cell or a battery?
Raymond Wang: Yes, definitely, because what the weather harvester does is it basically takes the charge generated by the piezoelectric material and it turns that into usable electricity, and it stores it on a device. And in my case, I just use a capacitor, but definitely with batteries that would work too. That would be like a future step in developing the product.
Steven Cherry: Very good. I think what you did was pretty incredible. Looking at the finalists, there are four of them that are either 13 or 14 years old, 13 being the youngest you can be to enter the fair and 18 the oldest. Do you think more teens could be doing serious engineering?
Raymond Wang: I really think that engineering can really make a difference in the lives of other people, because what you’re doing is creating a design that can really impact and better the lives of other people. And so from doing science fairs, what I’ve really learned is that when you take a simple idea and stick to it and develop it, you can really go far in making it known to the world. And from that step on, you’re really getting closer and closer in making a practical difference.
Steven Cherry: Do you think it’s just a matter of putting the Xbox aside and taking a shot at it, or is there more to it?
Raymond Wang: Well, I mean when you get an idea, just go with it. You never know where it can go, and I just really think that as long as you’ve had that spark or anything that you’ve thought about, really pursue it instead of thinking, “Oh, I can’t make a difference.” Because really, when you develop it to a certain state and when it’s known to the world, you really have that potential in making a difference.
Steven Cherry: So, what are your plans? Are you going to stay with engineering?
Raymond Wang: Well, doing science fairs has really helped me consider doing science as a career in the future, and that’s really again because you can make a difference in people’s lives by doing something as simple as having an good idea and sticking with it. And so I’m perhaps looking into the more practical fields and bringing the work I’ve done into real life.
Steven Cherry: I guess I’m wondering if you’re going to stay with this and really try and see it to some sort of commercial fruition.
Raymond Wang: Yes, definitely. I am currently developing it further. This is a project that I started around one or two years ago, and I’m just going further with the design, with my piezoelectric materials, just choosing perhaps even more efficient materials, looking at my circuit, trying to redesign it and trying to make it more efficient, as well as increasing the overall performance of the weather harvester. And so really even with my small model, I think I could collect a pretty substantial amount of energy, and perhaps with this on a real-life roof I could really get energy that could help power the home.
Steven Cherry: Yeah, I mean quite a bit of the home’s energy is just used in things like lightbulbs, and I guess if you were able to power a lightbulb with really less than a square foot of material, a roof would contain, I don’t know, 100 square feet of material. It’s quite a bit of power we’re talking about, really.
Raymond Wang: Right, yeah. So really with mine, I just had a little model that’s about the size of a sheet of paper, and considering the sizes of the roofs of real houses, that could be substantially more energy that is collected.
Steven Cherry: Well, it’s a terrific project, and I hope something really comes of it. In any event, you obviously have a terrific future ahead of you. Good luck, and thanks for your time today—and thanks to your school principal also, who helped set this up.
Raymond Wang: Thank you very much for having me.
Steven Cherry: We’ve been speaking with Raymond Wang, a student in British Columbia who came up with an energy collector that turns rooftop rain into usable electricity. For IEEE Spectrum’s “Techwise Conversations,” I’m Steven Cherry.
Announcer: “Techwise Conversations” is sponsored by National Instruments.
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