Originally Posted by haydnfan
How would anybody know that? There have been no real world tests of the new nook.
At one page a minute the old nook lasts for 150 hours if read continuously. If the advertising is correct than with the glow light on the new nook should last for 75 hours. A typical tablet lasts for at most 10 hours. Sounds like good performance to me.
Probably not. The metric of # of page turns at 1 turn per minute until battery exhausted doesn't hold over to the glow light. The only metric that the glow light is used in is half an hour of reading for 1 month (call it 30 days) versus half an hour of reading for "over" 2 months for the glow light off (call it 60 days, round down to be pessimistic).
The difference is that 1/2hr a day for 60 days with wifi off is assuming that the ebook reader is sleeping the rest of the time, which uses up a lot more power than off. I burn about 1% charge per hour of reading or a little less (maybe every 75 minutes) at the rate I read, but mine burns about 1.5% per day sleeping. That says that for maybe 75 minutes of reading you get about 1%, but each day uses 1.5% charge or a little less. Granted the numbers don't add up perfectly to 100%, but by the math on the use I get out of my nook ST I have about 30 hours of reading and 60 days, using about 30% of the battery charge for reading and 90% of the battery charge for being in sleep mode, at any rate, take it as a 3:1 ratio at any rate and lets call it 120 units of power.
If you go down to 30 days of sleep time and 15hrs of reading with the glow light on, or half of before, you get 45 units of power used by sleeping because you have half the sleep time. At the same time you also only use 15 units from general reading because you have half the sleep time. That is 60 units used by reading and sleeping and 60 units used for 15hrs of glow light use. Or 1 unit per hour for reading and 4 units per hour for the glow light.
Horribly unscientific and probably not entirely accurate. However, if you use B&N's stated usage numbers, that to me says that most likely with the glow light on (they don't specify and intensity, but I would assume 50% brightness) the glow light is going to drain the battery about 3-4x faster while reading at night than reading with the glow light off. Or in other words, you'll probably burn through about 3-4% per hour of reading with the glow light on compared to maybe 1% per hour with it off.
Still not bad, but I'd expect a cram session taking only breaks for quick naps, bathroom and eating you litterally go 3 or 4 days of straight reading before the battery would die. With the glow light on you might get 24hrs of straight reading.
Still way better than a tablet, but at the same time, we are talking the area of 20-30hrs with glow light use absolutely best case scenario.
In my situation I tend to get around 30-35 days before I hit 20% charge reading about 75-90 minutes per day. If I used the glow light at 50% brightness for all of my reading I could probably expect to hit 20% charge in maybe 10 days, possibly 2 weeks if I was lucky. That said, if I used it at lower brightness and especially if I only used it at night reading in bed (which is about 20% of my reading), probably I'd only see a hit of a few days to battery life.
A post longer than really necessary, and I think owner's use will bare out just how much of a hit on battery life it will really have, but I think owners who use the light all the time, especially turn up high for better readability indoors in moderate lighting are going to see a massive hit to battery life. Those who use it near minimum brightness and only occasionally at night in bed or in dim rooms probably are going to see a very modest impact on battery life.