Charger that allow for charging from 12V: http://www.rakuten.de/kamera-ladegeraete/patona-akku-ladegeraet-panasonic-lumix-dmc-gh2-469058026.html?utm_source=preisvergleich&utm_medium=cpc&cid=idealo&utm_campaign=idealo-2010-06&sclid=p_idealo&cp_id=2074550

Solar Module: http://www.solarzellen-shop.de/12v24v-solarkoffer-tragbare-solarmodule/5-watt-12v-solar-ladegeraet-duennschicht.html (Careful.. this is only 5W in bright sun.. so it will take some time.. but only 1 Kg)

I suggest to put this in parallel to the output of the solar panel, it will buffer the power: http://www.online-batterien.de/shop/Effekta-BT-12-12-12V-12Ah-Bleiakku-Blei-Vlies-Akku (0.6 Kg)

Just ideas, not tested. ;)

http://www.solarzellen-shop.de/12v24v-solarkoffer-tragbare-solarmodule/4-watt-12v-solarkoffer-autobatterie-solar.html

;-)

I would get the charger and the battery first, then measure how much is needed to charge one lumix battery. Then decide about solar panel.. you don´t want a solution that needs 2 days to charge one battery.

I don't know if they would work for this need, probably a bit weak and inconvenient plug-wise, but there are many practical solar panel-battery packs on ebay. Perfect for rucksack charging

EDIT: here is a cheap version of what I'm thinking of. The more expensive ones have a lot more connetions and power/capacity

http://www.ebay.com/itm/Solar-Battery-Panel-USB-Charger-for-MP3-Cell-Phone-PDA-Black-/170852950596?pt=LH_DefaultDomain_0&hash=item27c7a12244

Once I took two 5w foldable solar panels to the mountain for a documentary, I had 4 batteries and there was plenty sun, I never run out of power but did not do a lot of filming per day. The batteries charged in 4 to 6 hours each that is why I had two of them. They where something like these: http://www.ebay.com/itm/NEW-PowerFilm-F15-300N-5W-Foldable-Solar-Charger-Panel-12v-/230799204291?pt=LH_DefaultDomain_0&hash=item35bcb45fc3

You could step on them and leave then in the rain, and most importantly they where really light.

if you put them in parallel you have more watts so they charge faster

I just posted on Voldemort and dpreview forums before I found this thread - and was wondering if there has been any better developments in lightweight solar rechargers for camera batteries, since when you all discussed this about 18 months ago?

I have been looking for the best lightweight portable setup. I do alot of landscape and travel photography where I go in hiking for a few days etc. There is alot of stuff on the web and one that looks alright is the GoalZero Nomad 7. It has 7 watts so is stronger than the one Andre suggested, but it weighs almost twice as much (battery pack included).

I have a Panasonic Lumix GH2 which has a mains plug recharger, but with no other outlets for USB recharging or anything like that. It seems that if I get a Panasonic DC coupler, which is used for linking to a rechargeable battery kit, then that should plug into the Nomad 7 kit, as it also has a rechargable battery kit. But I am not sure here either, whether the electricals are compliant.

Also wondering about recharging times too. On mains power these batteries can take several hours to recharge depending upon how dead they are. I have seen reviews for some of these solar rechargers where recharging times have been very slow for some people. So, hoping someone here has some experience in getting the right combination of power and travel lightness. Thanks.

thanks Mike, by the way, I posted "Voldemort", someone or some program has changed it to Voldemort, must be something from other world here . I have found so many different options with rechargable battery packs, solar cells etc, its really a bit bewildering and time-consuming going through all the conflicting reviews to figure out whats a good product.

Your link looks promising, so an ideal situation with the Lumix battery charger you recommended, would be the ability to hook it up to a solar cell charger, and/or a battery pack like this one at 23,400 mAh: http://www.amazon.com/gp/product/B00FDK2G2C/ref=ox_sc_act_image_2?ie=UTF8&psc=1&smid=A1HG0SD62RRE2I.

This pack might be far more than needed, about twice what someone recommended here earlier and it weights a pound, which would blow out to 2 lbs in your rucksack by the time you added the DC coupler, spare batteries and battery charger.

From what I have seen on youtube etc (

), you can hook up a battery pack like this to a DC coupler and run it straight into the camera, and use the camera while it is charging, strapping it to your tripod head or something.

It doesn't tell you if the battery can recharge by itself, simply hooked up to the Panasonic DC coupler (http://www.amazon.com/gp/product/B004OZQIGW/ref=ox_sc_act_title_4?ie=UTF8&psc=1&smid=ATVPDKIKX0DER)

A good set up might be: Lightweight solar panels >>>Hi Energy battery >>>panasonic DC coupler or battery charger.

Of course you can get solar panel/battery pack combos like the Solar Gorilla (https://www.powertraveller.com/en/shop/portable-chargers/outdoor-adventure/), but again, not 100% certain how good it all is with Panasonic GH2's, probably does the job, one person said his 5DII batteries recharged OK on it. But Canon have a special relationship with this brand.

Well this is a bit long, hope it can point others in the right direction, my guess is that there will be much more demand for lighter and more powerful units

they look pretty nifty and affordable

The 12 Watt Solar Charger Kit (2 6w-panels in series for a 12 v output) is interesting. In theory it should charge a battery in 2-3 hours. But the kit needs to be placed on the backpack and ideally the hiker should walk with the sun on the back in excellent weather conditions. Far from a realistic situation. However it is encouraging.