I am taking my HVX202 with a couple of Panasonic batteries into Nepal this October. For a period of 26 days, there won't be any AC power socket to plug a battery charger into. Does anybody have any experience using alternate power sources (other than solar panels - which I have lots of experience) to allow charging of the Panasonic Lithium batteries? Stuff like - Fuel Cells for charging batteries? I have a 3rd party charger for Panasonic batteries which takes 12V DC - so, if I can generate that 12V DC reliably, I can charge it anywhere in the field.

Other than a clockwork charger (if you can find one) I think solar panels will be your only option. I don't think airlines would allow you to take the new fuel cell style powering options.

I did come across this though which might be better than previous solar options?
http://www.renewableenergyaccess.com/rea/partner/story?id=48362

I checked their website. I don't think it is available for sale to people like me. Anyway, I have a very powerful solar panel ... Unisolar's UniPac 30 - used in Everest expedition (Tibet side).

Will you have a vehicle (gasoline engine with 12VDC system)? In which case you could use an inverter (DC to AC converter).

I would prefer kerosene powered generator. Easier to find kerosene than gasoline in the mountains of Nepal. Are you aware of any good reliable websites where I can take a look? Don't need much power. The charger is able to take 12V DC as input. Something like 5Amps at 12V DC is more than enough.

If you used a generator like the Honda EU1000 you can get by with a gallon per day. If gasoline is hard to get you'll have to pack that in. 27 gallons would weigh 162 pounds, not including the five-gallon containers. The generator weighs just under 30 pounds.

Or you can go with a combination of solar panels and generator. Use the generator only when solar doesn't provide enough power. That way you reduce the amount of gas you'll need to haul.

Honda generator is way too heavy to lug into the mountains. Have to source for something lighter and smaller.

Honda generator is way too heavy to lug into the mountains. Have to source for something lighter and smaller.

How are you getting in there? And is there any sort of logistical support at all? Air drops? Pack animals? Sherpas? You're going to need fuel and food, and 27 days translates into a significant amount of supplies, whether it's batteries or freeze dried stew.

Sherpas and porters. No air drop. They use kerosene as fuel. Not gasoline. That's why I can't use the standard generators. Besides, it will be too noisy for the environment. Ideal - if I can find it -a salt water fuel cell. I did see it once at 'Fuelcellmart.com' - but, the Canadian company that makes it stopped making it. I can still fallback to my solar panels - but, it can't work at night.

To get the solar panel to work at night, shine a flashlight on it.... :-)

You might want to have two sets of batteries. One charging during the day while the other set is being used. It's a bit more weight but not as much as the other option of a generator. You should also figure in a certain margin to compensate for days of reduced sunlight.

Also, keep in mind that the available capacity of batteries diminish as temperatures drop.

The Honda EU series, by the way, is very very quiet. You'll have to see (hear) one in action to believe it. There was one running a hot dog stand outside of a CompUSA here and it was hardly noticeable. And considering it weighs about as much as a Betacam SP camera with an Anton Bauer brick and Vinten sticks, that's not bad (30 pounds).

But as gas is hard to get, well, that might not be a practical option.

Here's some info on how Everest expeditions get their power:

http://www.humanedgetech.com/story/EvrstpowrApr122004.shtml
http://www.pbs.org/wgbh/nova/everest/expeditions/97/higher2.html
http://www.mounteverest.net/expguide/communication.htm

Good luck. Sounds like a great adventure.

Looks like I am back to my old trusty solar panels then. This trek is going to Rara Lake - pretty low (as far as Nepal goes) - only 3,000m. Hence, it won't be that cold as those 5,500m elevations of most base camps. Petrol / kerosene electricity generators sounds like a good idea - but, too heavy for porters to carry (complete with petrol and kerosene).

How about hydroelectric or wind generators. Might have either

http://www.re-energy.ca/t-i_waterbuild-1.shtml

http://www.alpinesurvival.com/air-industrial_wind-turbine.html

This is a build it yourself wind turbine design: Looks doable !

http://www.mdpub.com/Wind_Turbine/index.html

Hydroelectric - have to find nearby river / stream. Not always so lucky to find a campsite near a stream. Most of the time, there won't be a nearby stream. Even if I can find one, have to run a long wire from the stream to campsite. Very dangerous.

Windmill - subject to the same restriction as solar panels .. if no sun, no electricity. No wind or low wind, no electricity too.

I have looking into this area for a long, long time. The best option (lightweight, can carry into planes, and can find fuel virtually everywhere) is an alkaline fuel cell. It uses salt water (or river water + salt) as fuel. A plate of electrolyte is used to convert it to running electricity. Generates 12V DC at 2amps. Very good. Pack it dry - drain out the salt water, and air it. Unfortunately, for some unknown reasons, the Canadian company making it decided not to proceed with production after running about 300+ units.

Forgive me for asking the obvious... but would it be possible to just bring along enough pre-charged batteries for the whole trip? Seems like it might be easier/lighter than some of the other suggestions here...

Unfortunately, no amount of pre-charged batteries will last a month's trek + filiming in Nepal. With nightly temperatures of 0 deg C or lower (have encountered minus 25 deg C before), all batteries will suffer. LiOn rechargeable batteries self discharge itself at a faster rate at colder temperatures than normal temperatures. Worse, at normal temperatures, one battery could last, say, 4 hours - but at colder temperatures, that battery will only last 2 hours - maybe less. Hence we must have a need to recharge (or top up) even fully charged LiOn batteries from time to time.