Powering a work environment from a bike dynamo?

January 15, 2013 4:59 AM

I'll soon be off on a big bike tour, and would like reccomendations for running a computer/tablet able to do actual work from a bike dynamo hub (details inside).

The work I will be doing is mainly word processing with internet research, and I am aiming to be able to charge the batteries of my device from the day's riding (as well as those of a Galaxy S III). My dynamo is a Shimano Alfine front hub limited to 6V 3W, and I'm considering the Tout Terrain Plug II to produce a reasonably steady USB 5v output.

My initial thoughts are to use an Alphasmart Neo II to draft things, and hook that up to a Nexus 7 with Ubuntu dual boot to finish. I'm very open to other suggestions for both components, and have been considering an OLPC but it appears to be very hard to get a modern model.

My requirements are these:

* Must be able to use Debian/Ubuntu, with chroot from Android acceptable if there's 2gb of memory as otherwise things lag.
* Enough power to be able to use Chrome for Google Docs/Drive.
* Ideally able to charge for 4-5 hours of work in a day's cycling.
* Reasonably robust, as I'll be camping almost every night and will at least occasionally be working under a tarp.

Any suggestions on how to do this are very gratefully received.

posted by jaduncan to computers & internet (29 answers total)

If you're gonna camp, the BioLite camp stove includes a Peltier-powered USB charger. That might take some of the pressure off for charging the Galaxy, at least.
posted by seanmpuckett at 5:17 AM on January 15

There are solar powered chargers available for smartphones and laptops. How much time do you have before you leave? (ie. are you restricted to purchasing in your neighbourhood)

This for example is one old example that came up in a search. There's more out there that you could set up as you cycle.

Cycle powered chargers have yet to go mainstream outside of the ones I've seen in East Africa.
posted by infini at 5:31 AM on January 15

If you're gonna camp, the BioLite camp stove includes a Peltier-powered USB charger. That might take some of the pressure off for charging the Galaxy, at least.

Yes, I did look at one IRL. I'm a bit leery of the moving parts in the fan though, and it's quite heavy for what it is given that I have reasonable survival skills and can make an efficient camp fire myself. I will also be away for at least half a year, and I wasn't sure that it would stand up to that much use.

TBH my main barrier is that most stuff seems to require at least 12v/3a to charge; I have trialled a ARM Chromebook, and were this not the base power requirement it would be perfect. I'm just not sure how to get to that voltage without making the bike impossible to cycle. I did wonder about a battery that can do charging from a USB port and 12v/3a output, but I can't find one. Anyone who does know of one would of course earn my undying love.
posted by jaduncan at 5:33 AM on January 15

I did wonder about a battery that can do charging from a USB port and 12v/3a output, but I can't find one.

Look for it online in China source sites such as Alibaba, meantime I will ask around for something that has been designed for the "developed" world/launched in that market. 12v is standard and there's a lot of small stuff I've got documented in those markets.
posted by infini at 5:36 AM on January 15

There are solar powered chargers available for smartphones and laptops. How much time do you have before you leave?

Oh, around 2.5 months. Lead/sourcing time shouldn't be an issue.
posted by jaduncan at 5:37 AM on January 15

People usually overestimate the amount of power they can produce or underestimate the amout of power their devices consume.

6V/3W? For the sake of argument, assume you get the whole 3W. At 5V, 3W is 600 mA. Will your computer run/charge on 600 mA? My iPad won't.

My Thinkpad charger is 18V at 4 Amps... (75W). Random Macbook chargers around here are 50-75 Watts.

Just saying...
posted by FauxScot at 5:38 AM on January 15

Check this out.
posted by infini at 5:40 AM on January 15

Look for it online in China source sites such as Alibaba, meantime I will ask around for something that has been designed for the "developed" world/launched in that market.

Well, thank you, that would be awesome.

My shortlist is basically as follows:

Nexus 7/Neo II: charges from USB port, 7 inches is enough to do work on given that for really big pieces it will be worth just using a net cafe.
Nexus 10/Neo II: charges from USB port, would be preferable work wise but slightly more power required.
ARM Chromebook: probably requires a battery in the middle.
posted by jaduncan at 5:40 AM on January 15 [1 favorite]

My Thinkpad charger is 18V at 4 Amps... (75W). Random Macbook chargers around here are 50-75 Watts.

Oh, I'm well aware that full laptops won't work in this application. The reason I'm looking at the Nexus devices is that they both charge from a USB port at 500mA.
posted by jaduncan at 5:41 AM on January 15

Will your computer run/charge on 600 mA? My iPad won't.

Apple has jiggered their innards so that their products don't charge from regular voltages and panels and connecters that are all easily available. iPhones are virtually unchargeable by the variety of solar lamp/mobile charge units sold. I do know someone who is working on this.
posted by infini at 5:42 AM on January 15 [1 favorite]

Goal Zero has plenty of solar charging products that will charge a laptop, tablet, or for that matter, run a TV (though I wouldn't want to carry the TV on my bike...)
posted by rockindata at 5:52 AM on January 15

Check this out.

It's pretty good, although I've heard very mixed things about how good solar panels are when constantly turning and moving on a bike. I'm tempted to steal the battery out of that or ask the makers for it as a spare part though.
posted by jaduncan at 5:53 AM on January 15 [1 favorite]

Can't comment on the rest, but I think you'll be very happy with the Alphasmart. I have one (a different model) and they're not kidding when they say "long battery life".
posted by daisyk at 5:55 AM on January 15

You could also grab the goal zero battery packs and charge them from your dynamo.
posted by rockindata at 5:56 AM on January 15

I think they've been discontinued (therefore cheap?), but the Motorola Lapdock might be of interest. It requires a compatible Motorola phone to work (unless you start hacking).
posted by Iteki at 5:56 AM on January 15

Yes, you are right to be concerned. iirc [from last year's projects] that the panels work best when moving with the sun's movement to be as close to a 90 degree angle. But maybe try googling for wearables that can used when moving before taking the battery only route? I"m sure someone's been working further on the direction of the 2004 prototype I linked to above? There's probably better quality and more efficient stuff out there, my exposure was to low cost affordable stuff.
posted by infini at 6:00 AM on January 15

Can't comment on the rest, but I think you'll be very happy with the Alphasmart. I have one (a different model) and they're not kidding when they say "long battery life".

Yeah, I'm optimistic. Neo II is rated at 300 hours plus on 3 AA batteries, is built for kids that try to eat them, and looks perfect for both work and keeping a journal that I don't need to turn the tablet/chromebook on for. Which model do you have and what's the keyboard like? I've yet to try one IRL, so trusting it for 5k+ pieces is a bit of a leap of faith for someone raised on Thinkpad keyboards.
posted by jaduncan at 6:09 AM on January 15

You could also grab the goal zero battery packs and charge them from your dynamo.

I would quite like to do so, but sadly even the Shepa 50 low weight, low power model requires an imput voltage of "15-25V, 2A (30W)". If I had the legs to do that, I'd just power the laptop directly. :)

I'm actually really astonished that the trickle charge, high output battery appears to be such an unpopular product.
posted by jaduncan at 6:12 AM on January 15

trickle charge, high output
posted by infini at 6:39 AM on January 15 [3 favorites]

OK, I actually LOLed.
posted by jaduncan at 6:41 AM on January 15 [1 favorite]

Mine is an Alphasmart 3000. I've had it for about three years and although the amount of use it sees varies, I've written large chunks of text on it with no problems. (I bought it for NaNoWriMo.) The keyboard does feel a little lighter than a ThinkPad's but I got used to it very quickly. I've had almost no issues with it; it did crash once, about a year ago. The AlphaSmart customer service people got back to me very quickly with instructions on how to reset it and I think there wasn't even any data lost. I recommend it often.
posted by daisyk at 6:59 AM on January 15

OK, I think that charging directly into the N7 is probably the best option here; the batteries that would work as a cache are quite heavy in and of themselves, and that means that I'm faced with a situation where the weight of panels/batteries both exceed the weight of the neo II keyboard and represent an extra point of failure.
posted by jaduncan at 7:01 AM on January 15

Mine is an Alphasmart 3000. I've had it for about three years and although the amount of use it sees varies, I've written large chunks of text on it with no problems. (I bought it for NaNoWriMo.) The keyboard does feel a little lighter than a ThinkPad's but I got used to it very quickly. I've had almost no issues with it; it did crash once, about a year ago. The AlphaSmart customer service people got back to me very quickly with instructions on how to reset it and I think there wasn't even any data lost. I recommend it often.

Cool. I'll be backing up the data to the N7 pretty much daily anyhow, and then to Google Docs as and when wifi is available (by mobile network if absolutely required; I've got a hacked up Kindle 3g but the data is limited to 50MB a month so I'm just going to use it as sparingly as possible).
posted by jaduncan at 7:15 AM on January 15

I have used the Goal Zero panel + battery pack on a bike tour. I got plenty of charge for my phone out of it, but I'll admit my power needs are less than yours. I was headed south on the Pacific coast, so direction of travel was fairly constant throughout the day, and it was easy to keep the panels pointed in vaguely the right direction. Also, just because it's suboptimal doesn't mean it will be inadequate - people dismiss solar for this reason ALL THE TIME when it would serve their needs well, IMO.
posted by yomimono at 7:48 AM on January 15

My trip will involve going far north of the Arctic circle at first, which makes me a little dubious about the prospects for solar due to the sheer atmospheric physics of it. Certainly I think the available elections are fewer than on the Pacific coast.
posted by jaduncan at 7:54 AM on January 15

Busch & Müller's LUMOTEC IQ2 also does USB charging, but the Tout Terrain stuff is gorgeous (if spendy).
posted by scruss at 8:27 AM on January 15

going far north of the Arctic circle

Suntrica Ltd from Finland is the leader in flexible and high-efficiency portable solar chargers. Suntrica's ergonomic and lightweight products provide the most convenient mobile charging experience.
posted by infini at 8:29 AM on January 15

Just to update everyone, it looks like I'm going with a Nexus 7, Neo II, Lumotec IQ2 and a very small Suntrica panel to keep the phone/GPS topped off when possible that's only 63 grams(!). Many thanks for all of your help, and especially to infini who has been a star.
posted by jaduncan at 4:57 AM on January 16 [1 favorite]

:)

Thank you for your kind words jaduncan. I look forward to subscribing to any travel blog you may keep and also your experiences with the various products off grid. Please do share when and if you start.
posted by infini at 5:05 AM on January 16