I’ve been seeing this article around for the past few months: “His Invention For Renewable Energy Inspired by the Physics of Northern Lights Just Won the 2020 Dyson Prize.” Carvey Ehren Maigue won a Dyson Prize for sustainability. He derives unnamed substances from waste fruits and vegetables, which he incorporates into colored solar panels. Whatever substance is in this invention absorbs UV radiation and radiates light in the visible spectrum, which then moves through this gel-like medium and is picked up by photovoltaic strips incorporated into the window frame. The idea is to get solar photovoltaic power even when the sky is cloudy.
A science popularization article will necessarily relate a simplified account of the science for the nonspecialist audience. This article doesn’t even do that. It’s on a general interest news site that doesn’t really cover science. It leaves a lot of questions unanswered. A few I’ve been able to fill in myself.
The picture with all the colored panes is not Maigue’s work. It’s the Montreal Convention Center. Those are ordinary colored glass. Maigue just gave that as an example of how a building fitted with his invention might look.
The reference to “Northern Lights,” in which ions radiate light in the visible spectrum, stimulated by solar UV radiation, must refer to how this tech gets UV to stimulate “luminescent particles” to radiate light in the visible spectrum. What exactly this stuff is, and how it’s extracted from waste produce and processed into solar panels, would be interesting to know.
Mapua University is a mechanical engineering school. I don’t think it has a PhD program. And I think that the Dyson awards are a student award for creative ideas.
He’s using fluorescent dyes to convert UV to visible light, and claiming that he’s doing it because solar panels are designed to absorb visible light, which is where most of the power in sunlight is, and that tiny solar cells on the edges will harvest useful power. On the face of it, this seems to be an ignorant idea, more typical of an architecture student, dreamed up by a mechanical engineering student who doesn’t know anything about solar cells, or solar output, or, being young, much of anything.
But hey, what do I know?
Now he’s looking to see if he can find any local vegetable dyes to replace the fluorescent dyes he’s using. Finding local vegetable dyes is something people have been doing for all of human history, so I doubt he’ll find anything new, but every generation is interested in different characteristics, so it’s possible, and this activity is not a total waste of time.
The actual target seems to be a locally produced colored pane of glass that glows on dull days: not magic but there could be a small market, that might sustain a small company.
If you want solar panels that make use of ultraviolet, then you should… make solar panels that make use of ultraviolet. That’d be a lot more efficient than fluorescing UV into visible and then using the visible.
It sounds like you might use these dyes to make extra-pretty stained glass art, though. That’d be nice.
Trying to figure out what was up with the vegetables, I found one video of Maigue crushing fresh turmeric with a mortar and pestle and pouring out the juice. So vegetable dyes are the analogue of aurora borealis? Turmeric is just all kinds of popular these days, isn’t it?
Here’s the best explanation I’ve seen, on the Dyson site (where else):
Most interesting is the solar energy harvesting density, and the relatively easy and cheap way it can be used to replace conventional building cladding.
It works:
on vertical surfaces
even in cloudy weather
even facing away from direct sunlight
Those are huge pluses compared with standard solar panels.
Presumably these dyes are added as a coating on the glass or are sandwiched between two panes in a sealed unit or something? I can’t see how vegetable pigments are going to survive being actually incorporated into the glass itself.
It looks like a thin gel sheet laminated onto glass panes. A view of one of those gel sheets edge-on showed it appearing to luminesce or fluoresce or whatever it does.
… uses the same technology derived from the phenomena that governs the beautiful Northern and Southern lights. High energy particles are absorbed by luminescent particles that re-emit them as visible light. Similar type of luminescent particles (derivable from certain fruits and vegetables) were suspended in a resin substrate and is used as the core technology on both devices. When hit by UV light, the particles absorb and re-emit visible light along the edges due to internal reflectance. PV cells are placed along the edges to capture the visible light emitted. The captured visible light are then converted to DC electricity.
In other words, it’s not glass, but resin. It’s stable, strong, and seems to be slightly flexible too.
Also:
Conventional PV cells lack the capability to capture high energy UV light. Creating better materials with such capability has been the journey for 2017 but led to failure.
A candidate to mediate the light degradation principle is the use of Quantum dots. Come 2018, quantum dot technology has been researched but proved to be costly and would take along time to be market ready.
I’m surprised that everyone commenting here seems to be starting from the assumption that Dyson is stupid.
There’s a reason this technology beat many hundreds of other entries to win the award.
Thanks - that makes sense - so they are using internal reflection to channel the emitted light to the edges.
I think that’s fine - but I feel like this is going to be one of those things that is outperformed by a synthetic version of the same concept; the idea of reducing waste by extracting dyes from vegetables is great for winning an award that is themed on sustainability and such, but in the real world, the vegetable waste can just be composted, or digested for biogas, etc; it’s one of the less-troublesome waste streams.
The re-emission is an explicit feature of the design - the UV fluoresces inside the material, emitting light that is trapped inside the material by internal reflection, emerging at the edges - so you get visible light going (more or less) straight through, with the UV being split out and channeled to the frame. A direct UV-sensitive solar panel could not be used in the same way.
In order to use direct-UV solar cells in a similar situation, you’d have to make them transparent to visible wavelengths.
UV makes up only about 4% of the energy in sunlight- compared with 42% visible and 54% infrared. Even if it works as described, is there really that much to be gained here?
Unless there are hard numbers for efficiency and power generation, rhis isn’t much of a story. The amount of energy in UV light that could be extracted this way sounds pretty trivial.
This reminds me of the ‘nuclear diamond battery’ story that made the rounds recently. Everything in the story was true, but the power generating ability was so tiny it had extremely limited application.
Because there is so much money available, it pays to be extra wary of radical new ‘green tech’ claims.
I think projects like this have some value in that they provoke discussion and thought - they make people feel it’s worth trying stuff and investigating materials and technologies - basically, PR for STEM, which is not entirely a bad thing.
Maybe. Or they convince people that there are magic solutions to very hard problems if we just ‘try hard enough’, and therefore they don’t actually have to make hard choices.
In the meantime, scammers are making bank on magical ‘green’ technologies like the Waterseer, or the PlayPump, or solar freakin’ roadways, or other ‘disruptive’ green tech that actually doesn’t work, or doesn’t work at scale.
No, those are not huge pluses compared with standard solar panels.
This is what I meant by “a mechanical engineering student who doesn’t know anything about solar cells, or solar output, or much of anything”.
The idea that vertical solar cells are good is so obvious that it has been thought of a million times, and the reason that we don’t have vertical solar cells is that it’s a worthless idea.
These are all just ‘feel good’ ideas not backed by physical reality. The amount of light traveling parallel to the ground is very low, so vertical cells don’t capture much energy at all: solar cells get much of their solar energy from the sky (ambient light): and solar cells are optimized to match the energy of solar radiation: putting a filter in front that blocks visible light reduces the amount of energy available.
Dyson rewards creative thinking to solve problems, which he personally thinks is important, and this particular award rewards exactly the same kind of ideas that have been rewarded in countless other student awards with similar aims. It’s not evidence that Dyson is stupid: it’s evidence that he wants people to think outside the box, that he’s interested in manufacturing (this awardee is actually making something), and that his award organisation knows nothing about solar cells.
There’s a big difference between “I’m an author” and “I’ve written a book”, and the same enormous difference between “I did a final year project” and “I’ve made something”. That’s worth rewarding right there, even if the result is not what you originally intended.
Yeah, giving someone an award like this doesn’t mean they’re the next Elon Musk. Most people aren’t Elon Musk. Heck, Elon Musk usually isn’t Elon Musk. If you waited for truly revolutionary ideas to give out your award, you’d be waiting a long time.
Ultimately, what this is lacking is cold, hard numbers. Don’t give me infographics with thumbs-up icons: Tell me how much it would cost to install one of these systems, and how many kilowatts that installation will produce. Preferably with a comparison to costs and powers for other technologies.
Aye but neither is it to be automatically dismissed without the numbers.
Potential pluses. Gaining energy out of large surfaces that would otherwise not be used for energy generation - windows - with a relatively small number of cells. “Trivial” amounts of energy multiplied by large area can add up to a useful small amount if the net cost per unit energy is small enough.
Is it? Could be. Or not.
There are others in the “solar window” space. No idea if they’re cost effective. Would this do better?
The fact that numbers aren’t available is a big warning flag.
Still, research like thus can be valuable, and I’m a big fan of stimulating ‘out of the box’ thinking and of having diverse ways of carrying out and funding development.
The problem is tgat in the hands of irresponsible media looking for clickbait, every little idea likd tuis gets hyped as a ‘potential breakthrough’, or ‘Is this the tech that will save us from climate change?’ Someone scales up a quadcopter to carry a human, and we get breathless articles about the ‘new era of flying cars’ written by J-school grads who know nothing about anything.
Power geneeation is a very mature field. Advancements are made on the margins, not in breakthroughs from grad students. Light has specific properties and carries a certain a,ount of energy, and nothing will change that. People keeping hoping for big battery breakthroughs, but the last major,one was Lithium-Ion, and the first lithium-ion battery was made 36 years ago. Improvements in batteries since then have largely been around packaging and the circuitry to charge and majntain them without exploding. We’ve made some gains in longevity and charge rate, mainly by packaging them differently and moderating them better with electronics.
There seems to be a lot of people willing to charge ahead with a renewable grid without having a current power storage system that works, confident that the smart people will find ‘breakthroughs’ in battery tech any day now. I think this attitude is especially common in Silicon Valley, where Moore’s law has resulted in the ‘disruption’ of many industries, and peoplle who witnessed it think similar disruptions can be made in other fields.
Have a look at aviation to disabuse that notion. Airplanes are generally slower now than they were 50 years ago, and other than high-bypass turbofans there haven’t been many gains in efficiency either. And in private aviation the price/performance curve is getting worse by the year. There hasn’t been a ‘breakthrough’ in aviation since the iet engjne. Just sequential marginal improvements where they can be found that saves a percent or two here over time.
We should be planning our future infeastructure based on the tech we have now. Betting the future of the planet on breakthroughs is a recipe for getting nothing done. Thus kind of stuff encourages peopke to do just that.
