this post was submitted on 09 Jul 2023
292 points (100.0% liked)

Technology

58837 readers
4515 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related content.
  3. Be excellent to each another!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, to ask if your bot can be added please contact us.
  9. Check for duplicates before posting, duplicates may be removed

Approved Bots


founded 1 year ago
MODERATORS
 

Tesla speculated electricity from thin air was possible – now the question is whether it will be possible to harness it on the scale needed to power our homes

you are viewing a single comment's thread
view the rest of the comments
[–] riskable@programming.dev 8 points 1 year ago

10mA @1.5 volts is plenty for all sorts of things! Just two of those things and you've got 10mA @3V which is more than enough to power a Bluetooth Low Energy microcontroller and some occasionally-lit LEDs, displays, sensors, buttons, etc.

Simple, real-world example: Nest sells these remote temperature sensors that you can place around your home to use any given location (e.g. your living room) as the place where you want the thermostat temperature setting to apply. They take a 3V CR123A battery that needs to be replaced about every 3 years.

A CR123A battery only holds about ~2.4 watt-hours of power. That's 2500 milliwatt-hours or 250 hours of 10mW @3V. That means the Nest temperature sensor uses about 0.0095mA of current (@3V). In reality it uses a lot more than that; it just stays in a sleep state nearly all of the time and only powers up every few minutes when it needs to take a temperature reading and send it to the thermostat.

TL;DR: Just one or two of these energy harvesting devices could power a Nest temperature sensor forever (assuming they don't wear out or lose much efficiency over time).

There's zillions of low-power devices that today use batteries (that often corrode and need to replaced every few years even if they might not run out of power) that could be powered by these humidity power harvesting devices. It could change low-power engineering forever!