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Not great, but better than I personally expected: "Inductive charging is not as efficient as direct charging [...] An analysis of energy use found that charging

by iSnow 5y ago

Not great, but better than I personally expected: "Inductive charging is not as efficient as direct charging [...] An analysis of energy use found that charging a Pixel 4 from 0 to 100 percent on a classic cable used 14.26 Wh (watt-hours), while doing so with a wireless charger took 21.01 Wh, a 47 percent increase. " https://en.wikipedia.org/wiki/Inductive_charging https://en.wikipedia.org/wiki/Inductive_charging Of course problems like heating up the battery and the huge amount of power needed if everyone does it remain.

avianlyric 5y ago
I did some maths (which maybe some should double check), but for an iPhone with a 12 wh battery. Doing a complete charge cycle everyday would consume an extra 5.6kwh over a year! Far more than I expected.
- maccard 5y ago
  or $0.70 per year at current energy prices.
  - zatarc 5y ago
    Germany: hold my beer! 1.78€ or $2.09 But thats not point here. Everyone is talking about the climate change and then we want to charge millions or billions of phones with ~50% extra power? Good idea!
    - maccard 5y ago
      In absolute terms it's nothing though. An average household uses 4000 kWh of electricity in the UK (less than half of the average us household), so saving the 5kWh on 4 phones is a 0.5% saving, which is roughly equivalent to running your home boiler for 10 minutes per year. Turning off your thermostat for one evening would have the equivalent impact of not using a wireless charger for a century.
      - throw0101a 5y ago
        > In absolute terms it's nothing though. Symbols can hold power though.
        maccard 5y ago
        Do we not have enough symbols? Plastic bags, domestic recycling, plastic straws are all strong "symbols" and yet we're still fighting about a couple of kWh rather than making any meaningful change.
    - swebs 5y ago
      Sure, as long as the electricity doesn't come from fossil fuels. Why not?
InsomniacL 5y ago
"900 million active iphones in use" - CFO Luca Maestri 14.26 Wh * 900000000 * 365 (days) = 4684 GWh/yr 46% = 2154 GWh/yr wasted energy That's about the total energy output of Madagascar with a population of 27 million people. There's a lot of reasons why the above numbers are wrong but I just wanted to highlight that at current efficiency, there would be a lot of wasted energy. :)
- saddlerustle 5y ago
  Thats about the energy demand of a single small aluminium smelter
- elzbardico 5y ago
  not exactly a lot of energy in the big scheme of things
  - jopsen 5y ago
    Yeah, it's not so much efficiency.. phones don't have that big batteries anyways. I would be more concerned about charging speed and heating. Inefficiency implies heating :) And wow, do I love charging my phone using my laptops USB-C charger.. it's just so fast! I don't really see the appeal of wireless charging. Faster direct charging would be a bigger win, IMO.

by iSnow 5y ago

avianlyric 5y ago

I did some maths (which maybe some should double check), but for an iPhone with a 12 wh battery. Doing a complete charge cycle everyday would consume an extra 5.6kwh over a year! Far more than I expected.

maccard 5y ago
or $0.70 per year at current energy prices.
- zatarc 5y ago
  Germany: hold my beer! 1.78€ or $2.09 But thats not point here. Everyone is talking about the climate change and then we want to charge millions or billions of phones with ~50% extra power? Good idea!
  - maccard 5y ago
    In absolute terms it's nothing though. An average household uses 4000 kWh of electricity in the UK (less than half of the average us household), so saving the 5kWh on 4 phones is a 0.5% saving, which is roughly equivalent to running your home boiler for 10 minutes per year. Turning off your thermostat for one evening would have the equivalent impact of not using a wireless charger for a century.
    - throw0101a 5y ago
      > In absolute terms it's nothing though. Symbols can hold power though.
      - maccard 5y ago
        Do we not have enough symbols? Plastic bags, domestic recycling, plastic straws are all strong "symbols" and yet we're still fighting about a couple of kWh rather than making any meaningful change.
  - swebs 5y ago
    Sure, as long as the electricity doesn't come from fossil fuels. Why not?

InsomniacL 5y ago

"900 million active iphones in use" - CFO Luca Maestri 14.26 Wh * 900000000 * 365 (days) = 4684 GWh/yr 46% = 2154 GWh/yr wasted energy That's about the total energy output of Madagascar with a population of 27 million people. There's a lot of reasons why the above numbers are wrong but I just wanted to highlight that at current efficiency, there would be a lot of wasted energy. :)

saddlerustle 5y ago
Thats about the energy demand of a single small aluminium smelter
elzbardico 5y ago
not exactly a lot of energy in the big scheme of things
- jopsen 5y ago
  Yeah, it's not so much efficiency.. phones don't have that big batteries anyways. I would be more concerned about charging speed and heating. Inefficiency implies heating :) And wow, do I love charging my phone using my laptops USB-C charger.. it's just so fast! I don't really see the appeal of wireless charging. Faster direct charging would be a bigger win, IMO.