850 Battery Life - OUCH!

TourleTour said:

Very much hoping to see an Edge 850 Solar coming out soon, but not holding my breath.

There wasn’t much benefit for solar with a more power-efficient unit. There’s going to be much less benefit for solar on the 850. I strongly doubt there will be a solar 850.

TourleTour said:

If the computer has higher consumption though suddenly the dynamo might not be enough, and I'm not just carrying one external battery, I'm carrying multiples.

Even being less efficient, the power demand of the 850 should be a small fraction of what a light would use.

The 830 uses a 750 mAh battery. The 840 and 850 likely use a similar battery.

On the Dcrainmaker video 850 has 1490mAh battery. Double capacity with such low battery life. 

@Pat Fulghum You need to learn how to use the device and set it up.

The battery is definitely better than the 840. Just set the display brightness to 50% (sufficient) and turn off automatic brightness. Battery life is 35 hours.

So according to DC Rainmaker (as reported by 8166212) the battery is 1490 mAh, nearly double the old battery. My Dynamo puts out a nominal 3W@6V, or around 500 mA, so each charge would take around 3-4 hours, allowing for conversion losses and the fact that it is consuming power as it is charged. If I'm using it for 20 hours a day that means two charges, so 6-8 hours.

My next big target race will have 11h 26m of daylight the day it starts, reducing through the race. I will spend at least one daylight hour every day effectively stopped to eat, shop, or carry/roll/drag the bike up (and down) rubble-strewn mountains and over rivers. If we average charging time to 7h that means I'm left with 3h 26m to charge all my comms equipment and my supplementary light. The 830 charges in about 2h and needs charging once a day... Actually it's probably about 3h of charging for a 20h day now, the battery has aged. So with the 830 I'm getting 7h 26m to charge everything else, which is over twice as long. That's a significant difference.

You're right about the benefit of solar reducing as the device becomes less efficient. It sounds like the new display is a big contributor to the increased power demand though, so I guess what I'm really hoping for is an 850 Solar with a more efficient display - I'm fine with the display on my 830.

dpawlyk said:

So, of all the devices and lights you are charging, most of the draw on the dynamo is the 830 (or 850)?

No, the 830 charges in a couple of hours, most of the draw (depending on the event) is my headlight, GPS tracker, or phone. With the 850 though I would not have capacity to charge everything I needed. Hence, I just won't get one, and when my 830 dies I will have to look at other options.

I'll keep an eye on the outcomes of the screen brightness discussion, and if I see one I can try out I will have a look at how it works at lower brightness, but my expectation (based on assumed competence at Garmin) is that the automatic brightness setting would already be representing close to the best compromise with this screen. Who knows though, maybe it is just way brighter than it needs to be for most people (or even just for me), most of the time. Now that I think about it, personalised automatic brightness settings would be a nice touch!

Anyway, if that doesn't work it'll be disappointing, because other than the battery life the 850 sounds good!