Nokia goes green with charger alerts: 'Please unplug the charger'

[Kiran.dks]

Nokia goes green with charger alerts
New handsets display 'Please unplug the charger' message

Nokia has clambered onboard the green bandwagon with three mobile phones that encourage users to unplug the charger from the wall socket when not in use.

The Finnish giant estimates that two-thirds of the total energy consumed by mobiles is wasted as a result of people leaving the charger idle in a live socket once the phone has been unplugged.

"We want to reduce this waste and are working on reducing to an absolute minimum the amount of energy our chargers use," said Kirsi Sormunen, vice president of environmental affairs at Nokia.

Nokia aims to reduce the amount of electricity a charger consumes while still plugged into the mains, but not the phone, by an additional 50 per cent by 2010.

Nokia phones already have an onscreen alert to say when charging is complete. The new alert appends the words 'Please unplug the charger' and provides an audible beep.

However, the company was unable to say how this would work for the millions of people who charge their phones overnight while asleep.

The alerts will be implemented initially on Nokia's 1200, 1208 and 1650 models, targeting high-volume sales in developing markets like India, China and Latin America.

Nokia said that the new alert will be rolled out across the whole range at a later date.

Source

[mobilegeek]

Good, thx for posting
-
but why cant they just put something to cut the power completely from the phone after battery is fully charged.
like putting a cut-off in charger itself

[infra_red_dude]

that cut off mechanism is present in all charges. its that there is a small power consumption even when it is unplugged from the phone but plugged and turned on form the mains. there a small power loss in the components. but this insignificant loss when multiplied by million times (no. of users around the world) leads to a large number. this is what they wanna curb.

btw mobilegeek, long time no see...

[Kiran.dks]

Yes. This kind of power loss can't be stopped unless untill the charger itself is removed from the mains. Some R&D can be made to cut-off the main power supply to the chips at the entry stage itself. i.e. before stepping down the power.

[hemant_mathur]

Great step.

[gauravakaasid]

good thinkin on nokia's part

[infra_red_dude]

Originally Posted by Kiran_tech_mania

Some R&D can be made to cut-off the main power supply to the chips at the entry stage itself. i.e. before stepping down the power.

thats the problem! the modern day chargers do not use the transformer for stepping down the voltage and a conventional rectifier. they use ics for it (more precisely opamps). they are single ics which will step down the voltage and also rectifiy the ac to dc.

as always, theres a minute leakage current present which results in small power consumption. no amount of r&d can make it compltely zero. for that we need to operate the circuit at absolute zero (zero kelvin, -273 deg C) which is obsv. not possible. so at the moment this problem can only be solved by unplugging the charger from the mains.

[Kiran.dks]

Originally Posted by infra_red_dude

thats the problem! the modern day chargers do not use the transformer for stepping down the voltage and a conventional rectifier. they use ics for it (more precisely opamps). they are single ics which will step down the voltage and also rectifiy the ac to dc.

as always, theres a minute leakage current present which results in small power consumption. no amount of r&d can make it compltely zero. for that we need to operate the circuit at absolute zero (zero kelvin, -273 deg C) which is obsv. not possible. so at the moment this problem can only be solved by unplugging the charger from the mains.

That's not my point. I am telling to make a circuitry which will cut of the input power supply before it is processed. That's as good as switching off the charger. Got it? It's not that tough to implicate it. Digital switches can be used to finally trigger a switch which will cut off the input power. The only worry factor is to handle 240V at the input. Hence life and ruggedness of the charger becomes the limiting factor.

[infra_red_dude]

yeah but digital switches will also haf leakage current of the same magnitude and hence defeat the whole purpose!

[Kiran.dks]

Originally Posted by infra_red_dude

yeah but digital switches will also haf leakage current of the same magnitude and hence defeat the whole purpose!

Again you are misinterpreting. Digital switches can trigger a value and then shut-off without consuming power. Once the mobile gives the signal that it is fully charged, it triggers a switch coupled with the main input and makes the value '0' and changes it's state. At this stage, power is completely cut-off from the mains. Next time when the state is changed, it allows the power to flow. For simplicity, you can relate it to "Power" button of computer. Once you click shut down, the computer turns 'OFF' totally. In our scenario, it is same as Mobile telling the charger that battery is fully charged and can shut down. The state of the power switch is changed when you press it to 'start'. Apply the same to charger now...Clear?

[Digit_Dragon]

That was a neat and clear explanation....
Gr8 news anyway.
Thanks

[infra_red_dude]

Originally Posted by Kiran_tech_mania

Again you are misinterpreting. Digital switches can trigger a value and then shut-off without consuming power. Once the mobile gives the signal that it is fully charged, it triggers a switch coupled with the main input and makes the value '0' and changes it's state. At this stage, power is completely cut-off from the mains. Next time when the state is changed, it allows the power to flow. For simplicity, you can relate it to "Power" button of computer. Once you click shut down, the computer turns 'OFF' totally. In our scenario, it is same as Mobile telling the charger that battery is fully charged and can shut down. The state of the power switch is changed when you press it to 'start'. Apply the same to charger now...Clear?

yeah... hope the cellphone companies read this!

[mobilegeek]

yeah the point is right that you guys discussed ... to make it complete Zero. right now i don't think there is cutoff in charger .. it gives the supply regularly.only the phone cuts it.2ndly untill the phone is connected to charger the battery is at 100%. if its cutoff then it should diminish over the time.

@Kiran_tech_mania nice man

@infra_red_dude Ya dude was busy in exams. thx for asking