[HN Gopher] Could solar-powered headphones be the next must-have?
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       Could solar-powered headphones be the next must-have?
        
       Author : adrian_mrd
       Score  : 21 points
       Date   : 2022-10-17 20:19 UTC (2 hours ago)
        
 (HTM) web link (www.bbc.com)
 (TXT) w3m dump (www.bbc.com)
        
       | gw99 wrote:
       | I didn't know BBC were running adverts these days...
        
         | _-_-__-_-_- wrote:
         | That was my first thought as well. It will be interesting to
         | see future applications of this technology. If they can get the
         | costs down and the charging is actually efficient enough, it'll
         | be worth it.
        
       | droopyEyelids wrote:
        
       | bawolff wrote:
       | Dont (non active noise cancelling) headphones already not use any
       | power?
        
       | flothebre wrote:
        
       | thatguymike wrote:
        
       | waterpowder wrote:
       | And as always...
       | https://en.wikipedia.org/wiki/Betteridge%27s_law_of_headline...
        
       | superkuh wrote:
       | No. The available surface area is too low.
        
         | UncleOxidant wrote:
         | Solar hats. The next must-have.
        
         | aetherspawn wrote:
         | We're not talking about powering a car here. Most headphones
         | have a tiny tiny energy draw to maximise the energy of their
         | tiny lightweight battery.
        
         | mthomasmw wrote:
         | 'Currently the tech can create one hour's worth of power "from
         | just 20 minutes of English or Swedish summer sunshine".'
        
           | LightG wrote:
           | So ... 20 minutes use per year.
           | 
           | Nice.
        
             | zdragnar wrote:
             | Presumably, it is referring to strength of sunlight at that
             | latitude. 3:1 runtime to charge time for strong solar
             | lighting really isn't bad at all if the cells are durable
             | enough for a wearable item and the speakers don't suck.
        
               | OJFord wrote:
               | I think GP is joking about getting just 6m40s of sunshine
               | per year in England/Sweden.
        
         | agumonkey wrote:
         | depends on what kind, you could have head-band style with thin
         | film over the surfaces and low power in ear transducers, i'd
         | probably buy none (granted the pv film doesn't degrade in a
         | year)
         | 
         | which reminds me that I regularly find old PV pocket calc, with
         | I forgot what kind of oxide they used, still working fine..
        
         | TOMDM wrote:
         | From the article:
         | 
         | "The solar-powered headphones still have a built-in battery
         | that can power up to 80 hours of playback time. It is this that
         | the Powerfoyle strip charges. Mr Fili says that currently the
         | tech can create one hour's worth of power "from just 20 minutes
         | of English or Swedish summer sunshine"."
         | 
         | A very bold claim, I do wonder if that's with the strip placed
         | optimally facing the sun, and not integrated into a headset.
         | 
         | The idea of a solar jacket to keep a hikers satellite phone
         | topped off sounds more attractive though.
        
           | abdullahkhalids wrote:
           | Back of the envelope calculations.
           | 
           | Assume:
           | 
           | * solar panel is about 1.5cm x 20cm = 0.003m^2 * Efficiency =
           | 10% * solar insulation is 1000W/m^2
           | 
           | Power = 0.3W
           | 
           | In 20 min you gain, 0.3 _1 /3=0.1Wh of energy.
           | 
           | Now, these Sony Headphones [1] have 30h life with a battery
           | of 3.7V, 1200mAh [2]. This means they consume 3.7_1200m/30 =
           | 0.148Wh per hour.
           | 
           | Seems like claim is roughly in the ballpark.
           | 
           | [1] https://www.amazon.ca/dp/B0863TXGM3 [2]
           | https://www.amazon.ca/dp/B08YQX76B1
        
           | marginalia_nu wrote:
           | Summer sunshine is also like an order of magnitude more W/m^2
           | than overcast winter day, at least up north.
        
       | akamaka wrote:
       | How powerful of a computing device could be powered by a small
       | solar panel these days?
       | 
       | We had solar powered calculators in the 1980s, but with chips
       | being so much more energy efficient now, I imagine we could build
       | a much more impressive device with no battery.
        
       | syntaxing wrote:
       | How often do people use their headphones outdoors? I would be
       | very surprised if the average time outdoor over the lifetime of a
       | headphone to be over 5%.
        
         | hnlmorg wrote:
         | Indoor solar powered devices have existed for decades (like
         | calculators). The article even explicitly states that these can
         | be charged from indoor light.
        
           | teraflop wrote:
           | Sure, there are pocket calculators that can run off of
           | ambient indoor lighting, but they have to be designed to run
           | on a truly _miniscule_ energy budget -- on the order of a
           | fraction of a milliwatt.
        
             | dspillett wrote:
             | You seem to have missed the second sentence in what you
             | replied to (and the relevant bit if TFA):
             | 
             |  _> The article even explicitly states that these can be
             | charged from indoor light._
             | 
             | These apparently can also gain useful charge from much
             | smaller energy sources than direct sunlight, including
             | typical indoor light levels. Even if it isn't enough to run
             | them indefinitely, it could extend their run-time between
             | plugged-in charges.
        
               | teraflop wrote:
               | No, I didn't miss it.
               | 
               | You'll note, if you read carefully, that the article only
               | says they can be charged from indoor light, which I don't
               | doubt is true. It doesn't say they can get a _useful_
               | amount of energy indoors. The only concrete numbers
               | quoted are for direct sunlight, which is several orders
               | of magnitude more intense than ambient indoor lighting.
        
               | dspillett wrote:
               | _> No, I didn 't miss it._
               | 
               | It seemed so, or that you were ignoring it, from what you
               | write. Perhaps offer more clarity in future to avoid such
               | confusion.
               | 
               |  _> the article only says they can be charged from indoor
               | light_
               | 
               | The article says they can be charged from indoor light.
               | Adding "only" there I think is needlessly negative. The
               | article goes on to describe how this is expected/hoped to
               | be useful, charging between uses even if (unlike direct
               | sunlight) it is not enough to maintain power during
               | prolonged use, which strongly implies a useful amount of
               | energy if thought to be harvestable in typical indoor
               | conditions.
        
         | SteveGerencser wrote:
         | I use headphones exclusively outside on our farm. All of the
         | equipment makes a lot of noise and decent headphones help with
         | the noise. And because my wife gets the 'new tractor' with a
         | cab, radio, and AC, I get the 'old tractor' and get to sit out
         | in the sun from sun up to sun down during hay cutting 3 or 4
         | times a year. I've yet to have a pair of headphone last a full
         | day. This could be cool and keep me from having to keep 3 pairs
         | on hand.
         | 
         | I freely admit that I am an outlier, but I'm used to people not
         | understanding that a large segment of the popular leads totally
         | different lives with totally different needs than most people.
        
         | metadat wrote:
         | The article states that the kind of PV charger they're using
         | works under any light source, including artificial lighting.
         | 
         | It's about half as efficient at converting light into
         | electricity as current best rooftop panels, and these ones are
         | way thinner.
        
           | teraflop wrote:
           | OK, but _efficiency_ at converting light into electricity
           | doesn 't mean much if the _total_ amount of light available
           | for conversion is very low -- which it is in almost all
           | indoor situations.
           | 
           | The illumination level in a brightly-lit office is typically
           | on the order of 300 lux, compared to 100,000 lux for direct
           | sunlight. (Residential spaces are often even dimmer.) So if,
           | as they claim, this device can gain 1 hour of charge in 20
           | minutes in direct sunlight, it would take on the order of 100
           | hours to collect the same amount of energy indoors.
           | 
           | The statement that "the panels can also create some power
           | from artificial light" is technically true, but "some" is
           | doing a lot of heavy lifting in that sentence.
        
             | metadat wrote:
             | > this device can gain 1 hour of charge in 20 minutes in
             | direct sunlight, it would take on the order of 100 hours to
             | collect the same amount of energy indoors
             | 
             | Depending how frequent and heavy of a user you are, the
             | economics may work out such that they'll be passively
             | charged enough and never require active charging.
             | 
             | Related idea: It'd be cool if cellphones could charge in
             | light whilst powered off. Then when they get old, they'll
             | sit around and always be topped up and ready to go.
        
         | OJFord wrote:
         | I only use earphones, just because I find it more comfortable,
         | but almost exclusively. I have no (extremely little) need for
         | them indoors, I (almost always) prefer speakers there.
        
         | [deleted]
        
         | dmd wrote:
         | I wear headphones constantly outdoors (walking/running) but
         | can't recall the last time I had them on indoors. If I'm
         | indoors I'm using good speakers.
        
         | eyelidlessness wrote:
         | Depends on the person I guess? Or maybe how much time they
         | spend walking. I used to use headphones almost exclusively
         | while walking, and generally only used stereo speakers at home.
         | I don't listen to anything while walking these days because I'm
         | generally paying full attention to my pup, music would be an
         | unwanted distraction. But I do see lots of other people wearing
         | headphones while we're out walking. And I don't have that
         | stereo anymore, I generally only use my MBP's built in speakers
         | at home now. I _really_ don't like wearing headphones at all
         | though.
        
       | FrankTheDank wrote:
       | The quicklook of these on LTT was pretty favorable. They actually
       | seem pretty neat. I prefer earbuds for running though so not for
       | me. Like the idea though
        
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