5 ms·

That LED by itself obviously doesn't use a lot of power, but it does imply more usage by other components. Last year I got a thermal camera to help with some i

That LED by itself obviously doesn't use a lot of power, but it does imply more usage by other components. Last year I got a thermal camera to help with some insulation in my old house, but it's great for literally seeing this standby usage. The TV, when off, is around 2 degrees above ambient. The author of the article laughs at the mention of the VCR, but doesn't acknowledge that we might be wasting more energy with newer gadgets. Every "IoT" device that runs of mains power seems to have very inefficient power supplies, because they are regularly warm to the touch even when doing nothing: Smart bulbs (by far the worst), Alexa, Fire/Google TV sticks, etc.

ericpauley 4y ago
> Fire/Google TV sticks Are you saying the device itself is warm or the power supply? If it's the device it can't be caused by an inefficient power supply because the supply is external.
- sdflhasjd 4y ago
  I mention power supplies in both the colloquial sense, but also the power supply circuitry - I know things like the ESP chips themselves don't use much power. As for my Google TV: the PSU is integrated, so I can't tell.
  - mordae 4y ago
    You have it right. Many cheap always-connected smart devices use Low-dropout regulator (LDO). What does wiki say about these? > The advantages of an LDO regulator over other DC-to-DC voltage regulators include the absence of switching noise (as no switching takes place), smaller device size (as neither large inductors nor transformers are needed), and greater design simplicity (usually consists of a reference, an amplifier, and a pass element). The disadvantage is that, unlike switching regulators, linear DC regulators must dissipate power, and thus heat, across the regulation device in order to regulate the output voltage. See for example: https://templates.blakadder.com/athom_PG01EU16A.html https://templates.blakadder.com/athom_PG01EU16A.html You can clearly see an AMS1117 (a super popular LDO), right next to the ESP board on lower right. Most LDOs have a chunk of metal tinned to the board so that the copper layer can help with heat dissipation. You can quickly identify them by this design. Here is another one on a dev board: https://hallroad.org/images/watermarked/thumbnails/465/465/detailed/24/Espressif_ESP32_WROOM_32D_Development_Board.jpg https://hallroad.org/images/watermarked/thumbnails/465/465/d... More on the topic: https://www.digikey.com/en/articles/use-adjustable-low-leakage-ldos-to-extend-battery-life-in-wearable-designs https://www.digikey.com/en/articles/use-adjustable-low-leaka...
  - PaulHoule 4y ago
    A device that's designed to handle 200W power peak might have a power supply which is 95% efficient, but it might be that you're paying that 5% all the time. (If, for instance, there is a big-ass transformer with a lot of iron in it you are making magnetic domains flip back and forth whenever the device is plugged in.) The standby mode might use 0.2W but the device burns 10W in the power supply. Old power supplies used ideas from analog electronics: if the voltage regulator was reducing the voltage from 10V to 9V then you are directing that extra volt (10% of the energy) into a resistor. More modern power supplies use digital ideas such that transistors are fully on or fully off. Because they waste less energy they have an easier time getting rid of heat, so they can be dramatically lighter and smaller... but more expensive. Other answers would be to add a second smaller power supply for the standby mode or run the standby mode off a battery or super-capacitor that charges intermittently. The cost of those improvements would definitely be noticed by the manufacturer and the consumer at the time of purchase. The consumer might not notice a small increase in the electric bill, even if it adds up to a lot over time, because it is against a high and noisy background.
CaptArmchair 4y ago
To my mind, advising people to "turn them completely off" is only part of the story. The other part is questioning why they are that wasteful in the first place. One explanation might be that it's a side effect of designing them to make their development and production cost effective. In that regard, I wonder to what extent consumer protection regulations would be helpful e.g. clamping down on the production of consumer electronics that consume certain wattage per hour without any proper justification.
eropple 4y ago
> Smart bulbs (by far the worst) Maybe some. On the other hand, the Hue sitting here is cold to the touch when not emitting light and is drawing about 0.4W right now--I checked.
- mordae 4y ago
  0.4W is a lot. WiFi-connected ESP32 draws about 140 mA. esp8266 will be similar. They are both 3.3V devices. 3.3 * 0.140 = 0.46 Your light bulb's esp8266 (or a similar chip, zigbee is 2.4 GHz as well) is fully powered. With a switching power supply and proper light sleep you should see about 1/10 of that. API reference: https://docs.espressif.com/projects/esp8266-rtos-sdk/en/latest/api-reference/system/sleep_modes.html https://docs.espressif.com/projects/esp8266-rtos-sdk/en/late... Sleep impact: https://github.com/chaeplin/esp8266_and_arduino/tree/master/_48-door-alarm-deepsleep https://github.com/chaeplin/esp8266_and_arduino/tree/master/...
  - eropple 4y ago
    Huh--I was certain it could be better, though I didn't realize it was that high! On the other hand, my electricity is hydro and it costs like $0.009 per kilowatt-hour.

ericpauley 4y ago

> Fire/Google TV sticks Are you saying the device itself is warm or the power supply? If it's the device it can't be caused by an inefficient power supply because the supply is external.

sdflhasjd 4y ago
I mention power supplies in both the colloquial sense, but also the power supply circuitry - I know things like the ESP chips themselves don't use much power. As for my Google TV: the PSU is integrated, so I can't tell.
- mordae 4y ago
  You have it right. Many cheap always-connected smart devices use Low-dropout regulator (LDO). What does wiki say about these? > The advantages of an LDO regulator over other DC-to-DC voltage regulators include the absence of switching noise (as no switching takes place), smaller device size (as neither large inductors nor transformers are needed), and greater design simplicity (usually consists of a reference, an amplifier, and a pass element). The disadvantage is that, unlike switching regulators, linear DC regulators must dissipate power, and thus heat, across the regulation device in order to regulate the output voltage. See for example: https://templates.blakadder.com/athom_PG01EU16A.html https://templates.blakadder.com/athom_PG01EU16A.html You can clearly see an AMS1117 (a super popular LDO), right next to the ESP board on lower right. Most LDOs have a chunk of metal tinned to the board so that the copper layer can help with heat dissipation. You can quickly identify them by this design. Here is another one on a dev board: https://hallroad.org/images/watermarked/thumbnails/465/465/detailed/24/Espressif_ESP32_WROOM_32D_Development_Board.jpg https://hallroad.org/images/watermarked/thumbnails/465/465/d... More on the topic: https://www.digikey.com/en/articles/use-adjustable-low-leakage-ldos-to-extend-battery-life-in-wearable-designs https://www.digikey.com/en/articles/use-adjustable-low-leaka...
- PaulHoule 4y ago
  A device that's designed to handle 200W power peak might have a power supply which is 95% efficient, but it might be that you're paying that 5% all the time. (If, for instance, there is a big-ass transformer with a lot of iron in it you are making magnetic domains flip back and forth whenever the device is plugged in.) The standby mode might use 0.2W but the device burns 10W in the power supply. Old power supplies used ideas from analog electronics: if the voltage regulator was reducing the voltage from 10V to 9V then you are directing that extra volt (10% of the energy) into a resistor. More modern power supplies use digital ideas such that transistors are fully on or fully off. Because they waste less energy they have an easier time getting rid of heat, so they can be dramatically lighter and smaller... but more expensive. Other answers would be to add a second smaller power supply for the standby mode or run the standby mode off a battery or super-capacitor that charges intermittently. The cost of those improvements would definitely be noticed by the manufacturer and the consumer at the time of purchase. The consumer might not notice a small increase in the electric bill, even if it adds up to a lot over time, because it is against a high and noisy background.

CaptArmchair 4y ago

To my mind, advising people to "turn them completely off" is only part of the story. The other part is questioning why they are that wasteful in the first place. One explanation might be that it's a side effect of designing them to make their development and production cost effective. In that regard, I wonder to what extent consumer protection regulations would be helpful e.g. clamping down on the production of consumer electronics that consume certain wattage per hour without any proper justification.

eropple 4y ago

> Smart bulbs (by far the worst) Maybe some. On the other hand, the Hue sitting here is cold to the touch when not emitting light and is drawing about 0.4W right now--I checked.

mordae 4y ago
0.4W is a lot. WiFi-connected ESP32 draws about 140 mA. esp8266 will be similar. They are both 3.3V devices. 3.3 * 0.140 = 0.46 Your light bulb's esp8266 (or a similar chip, zigbee is 2.4 GHz as well) is fully powered. With a switching power supply and proper light sleep you should see about 1/10 of that. API reference: https://docs.espressif.com/projects/esp8266-rtos-sdk/en/latest/api-reference/system/sleep_modes.html https://docs.espressif.com/projects/esp8266-rtos-sdk/en/late... Sleep impact: https://github.com/chaeplin/esp8266_and_arduino/tree/master/_48-door-alarm-deepsleep https://github.com/chaeplin/esp8266_and_arduino/tree/master/...
- eropple 4y ago
  Huh--I was certain it could be better, though I didn't realize it was that high! On the other hand, my electricity is hydro and it costs like $0.009 per kilowatt-hour.