How much power can we expect from rainfall?
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How much power can we expect from rainfall?
1–10 of 110 posts
Re: How much power can we expect from rainfall?
#2"Shockingly, and inexcusably in my opinion, the researchers only state the instantaneous power (50 W/m2) of their device..."
That's not entirely fair. If Nature demanded that articles be written defensively, anticipating possible misinterpretations from non specialists, they would be very different articles with lower bandwidth for the target audience, who already know the difference between average and instantaneous power. The journal would not be improved by writing for endgadget instead.
It would be nice to have an implications section that put the effects in scale, but hardly inexcusable not to.
Re: How much power can we expect from rainfall?
#3"Shockingly, and inexcusably in my opinion, the researchers only state the instantaneous power (50 W/m2) of their device..." That's not entirely fair. If Nature demanded that articles be written defensively, anticipating possible misinterpretations from non specialists, they would be very different articles with lower bandwidth for the target audience, who already know the difference between average and instantaneous…
"Shockingly, and inexcusably in my opinion, the manufacturers only state the clock speed (3.2ghz) of their CPU..."
I suppose it depends on the intent. If the intent is to impress you with numbers by giving you a seemingly "good" number, then they're being intentionally deceptive for the sake of getting published in Nature. Does instantaneous power actually matter in context, even to knowledgeable experts?
Re: How much power can we expect from rainfall?
#4I looked at this area a few decades ago and two approaches stood out as potential, though not stand out.
1) Roofs already collect a large surface area and funnel into a single point via roof guttering - so tapping the flow from the gutter run off would enable a viable volume of water turn a motor in the drain pipe as it descended and generate power.
2) Piezo electric generating from the roof, though was looking at a form of artificial grass format that would capture the wind as well as the rain hitting it, generating the vibrations to the base which would be a piezo element.
The first idea, maybe has some traction, though the volume of water (yearly rainfall) with roof surface area and the napkin maths didn't show a huge gain and bit of a limited market due to rainfall you would need to generate anything noticeable.
Second idea, kinda got mooted as roofs solar panels did better with the real-estate, and whilst for non south facing or some area's it may well been useful. Then the area's were solar is not as good due to latitude, well, then you have snow. So I kinda self-killed that avenue off as well.
Figured that tapping the drainage flow of water from a whole area combined would work better and for that need a organised drainage system all connected and yes you do get those. Though they are also the sewage system and with that, the cleanish flow of rainwater would be less common once you factor in the rest of the mix.
But I'm all for micro based generation, like a wall of small wind turbines instead of one large one and more aesthetic and palatable to add to existing buildings and area's.
Re: How much power can we expect from rainfall?
#5"Shockingly, and inexcusably in my opinion, the researchers only state the instantaneous power (50 W/m2) of their device..." That's not entirely fair. If Nature demanded that articles be written defensively, anticipating possible misinterpretations from non specialists, they would be very different articles with lower bandwidth for the target audience, who already know the difference between average and instantaneous…
I think it is pretty misleading if they just gave the peak device power density. As in the car analogy given in TFA, if you were to burn all 270 Calories of a single Snickers bar in a thousandth of a second, your device would have a peak power of about 1 gigawatt, comparable to a large nuclear power plant. Yet if your publication said you had made a 1 GW device instead of saying that your device could power a single average home for 17 minutes, you reasonably be accused of misleading. Surely a subtext of the research was that energy sources are important to humanity.
(Sidenote: Huh, a snickers bar can power a home for longer that I expected.)
Re: How much power can we expect from rainfall?
#6"Shockingly, and inexcusably in my opinion, the researchers only state the instantaneous power (50 W/m2) of their device..." That's not entirely fair. If Nature demanded that articles be written defensively, anticipating possible misinterpretations from non specialists, they would be very different articles with lower bandwidth for the target audience, who already know the difference between average and instantaneous…
Actually, having read the Engadget end of things, I can see exactly what the professor is saying in his blog post.
The potential energy capture from any rain-related technique is trivial, negligible is a better word. The article sounds completely clueless to anyone who understands the energy flow involved. The fact that it was written should be a professional embarrassment for that author.
The fact that the original paper was treated with any respect is yet another level of embarrassment. A high school science project sounds more believable.
None of the original ink / bits should have been wasted. But I suppose some sort of nanoscale power supply could be some potential use, so maybe, maybe, there's some redeeming value.
But not the way the paper or the article tried to spin it.
Re: How much power can we expect from rainfall?
#7I don't even have to read this article to know that the best way to harvest rainfall is already being done: rain flows into rivers and we already use hydroelectric dams!
Re: How much power can we expect from rainfall?
#8I looked at this area a few decades ago and two approaches stood out as potential, though not stand out. 1) Roofs already collect a large surface area and funnel into a single point via roof guttering - so tapping the flow from the gutter run off would enable a viable volume of water turn a motor in the drain pipe as it descended and generate power. 2) Piezo electric generating from the roof, though was looking at a…
Wouldn't the water back up and then you'd have to somehow contain a ton of water on your roof?
Re: How much power can we expect from rainfall?
#9I looked at this area a few decades ago and two approaches stood out as potential, though not stand out. 1) Roofs already collect a large surface area and funnel into a single point via roof guttering - so tapping the flow from the gutter run off would enable a viable volume of water turn a motor in the drain pipe as it descended and generate power. 2) Piezo electric generating from the roof, though was looking at a…
>Figured that tapping the drainage flow of water from a whole area combined would work better and for that need a organised drainage system all connected and yes you do get those.
If I'm not mistaken, the technical term for these broad-area drainage systems is "river"
Re: How much power can we expect from rainfall?
#10If you're at all interested in useless research (and not necessarily anything to do with ecology or the environment) I strongly urge you to check out the podcast "Improbable Research"[1]. I'm a long time lurker, but this felt so perfectly relevant I had to make an account and chime in.
It was started awhile back, then stopped. Recently a dear friend of mine [2] became involved in re-editing the episodes and releasing them again. I know they'd appreciate the support from like-minded individuals. Hope to see more submissions like this one. It's a great thought experiment.
[1]: https://www.improbable.com/category/the-weekly-improbable-re...
[2]: https://sethgliksman.wordpress.com/
EDIT: formatting.