How many watts does a plugged in MBP use?

KoolAid-Drink

macrumors 65816
Original poster
Sep 18, 2013
1,427
408
USA
I'm trying to be as frugal as possible with my electricity, so when a fully charged laptop is plugged in (ie, overnight or while I'm out at work), how many watts is it eating up?

This applies to both the 2-prong and 3-prong chargers.

Thanks!
 

Falhófnir

macrumors 601
Aug 19, 2017
4,630
5,136
I'm trying to be as frugal as possible with my electricity, so when a fully charged laptop is plugged in (ie, overnight or while I'm out at work), how many watts is it eating up?

This applies to both the 2-prong and 3-prong chargers.

Thanks!
What model? At most, it will be drawing the wattage that the charger is rated for (so 87W for the 15” touch bar MacBook Pro, for example).

0.087 kilowatts Times by 24 hours means 2.088kWh per day... less than a fridge and that’s when the computer is at max draw too! At about 14p per kWh, it’s literally pence per day...
 

KoolAid-Drink

macrumors 65816
Original poster
Sep 18, 2013
1,427
408
USA
What model? At most, it will be drawing the wattage that the charger is rated for (so 87W for the 15” touch bar MacBook Pro, for example).

0.087 kilowatts Times by 24 hours means 2.088kWh per day... less than a fridge and that’s when the computer is at max draw too! At about 14p per kWh, it’s literally pence per day...
rMBP 2015, 13 inch.

I guess the question I'm asking is, is it worth unplugging the charger to avoid "vampire" electricity use, when the laptop is fully charged?
 

Falhófnir

macrumors 601
Aug 19, 2017
4,630
5,136
rMBP 2015, 13 inch.

I guess the question I'm asking is, is it worth unplugging the charger to avoid "vampire" electricity use, when the laptop is fully charged?
Considering it’s pence per day anyway, the cost would be negligible - I wouldn’t leave it plugged in all the time personally, however, as that’s not very good for the battery.
 

jerryk

macrumors 603
Nov 3, 2011
5,941
3,002
SF Bay Area
Full charged and plugged in. In those conditions likely 1-10 watts. You are not using the machine so the only power needed will be to top off the battery which might 1% of the batteries 94 watts, or in worse case, lots of strange badly coded apps pulling power 10%.
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
30,463
10,272
California
  • Like
Reactions: jerryk
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.