The iPad seems 'greener' than using my MacBook.

[johnmoorejohn]

After a full charge, the battery last so long, and there is so little heat generated, I think using the iPad for web surfing and TV shows and movies is more energy efficient than using my MacBook. I usually don't care about whether I am green or not, but this seems like an obvious advantage that doesn't seem to be advertised. I would think Apple would have mentioned it as a feature.

 

[wombat888]

There are a lot of factors to take into account, including the manufacturing of the devices etc, but the nature of an iPad should mean it consumes less electricity than a device with a hard drive, optical drive, more powerful CPU etc.

Note that for battery life, there are two factors, how much energy the battery stores, and how much energy the device uses. It would be possible for a device to have great battery life while actually using more energy per unit of time, if it had a huge battery. But I don't think that's the case here.