Solar Power & Battery Recharging Systems

At our annual week-long summer mountaineering camps (“MCamp”), depending on the weather, you can generate solar power during the day and recharge your electronic devices during the evening.   MCamp participants are solely responsible for their own electronic devices and recharging needs.

Goal-Zero-Logo_4The Mountaineering Camp organizers primarily use Goal Zero solar panels and battery recharging systems.

Goal Zero Nomad 20 (large triple panel), Nomad 13 (medium double panel) and Nomad 7 (small double panel) solar panels displayed with a Goal Zero Sherpa 50 power pack.

Goal Zero portable “Nomad” solar panels come in 7, 13, 20 and 100 watt configurations (Note: you have to be careful not to overpower the battery you are charging – the GZ Sherpa 50 battery pack, for example, is rated for 30 watts – the GZ Sherpa 100 is rated for 45 watts – so a 100 watt panel could damage those battery packs –  the massive GZ Yeti 400 battery, on the other hand, is rated for 120 watts of input).  Goal Zero also makes higher watt rigid panels for fixed installations (e.g., long-term base camps or recreational vehicle roof-tops).  The higher the watts, the faster your batteries are recharged.  Nomad panels are designed to be linked (daisy-chained) together when you need to increase your solar recharging capacity.

Portable Nomad solar panels can charge your electronic devices directly if they are charged with a USB port or indirectly by charging them through rechargeable power packs (also called power banks).  Note: You are not limited to using Goal Zero power packs with Goal Zero solar panels; most third-party USB rechargeable power packs can be recharged with Nomad solar panels.

Portable rechargeable power packs can recharge your electronic devices using USB ports or, for the Sherpa power packs, using a regular wall plug with the optional AC inverter attachment or a car charger with the included 12 volt dongle.

Goal Zero makes 8, 10 and 30 watt-hour “pocketablepower packs, 50 and 100 watt-hour “portable” power packs and 150, 400 and 1250 watt-hour “luggable” (hernia time) power packs.  The larger the storage capacity, the more you can recharge (i.e., a single higher capacity item like a laptop or a number of lower capacity items like camera batteries or smart phones).

My Goal Zero Systems

Nomad 7 and 13 solar panels with a Sherpa 50 power pack.

The small 8-10 watt-hour batteries may fully recharge a smart phone once (or a GoPro once or twice).  This class of battery can be recharged by a Nomad 7 solar panel in about 4-8 hours.  These power packs are good for light use only.  If you have more than just one item to recharge a day (e.g., a smart phone plus a camera), I would highly recommend a more robust solution.

255205_a_venture_30_powerpack_goal_zero-190x243Goal Zero’s new 30 watt-hour power pack (the 7,800 mAh “Venture 30“) may recharge a smart phone up to three times (or a GoPro up to five times).  The Venture 30 (the size of a deck of playing cards) can be recharged by a Nomad 7 solar panel in 8-16 hours; by a Nomad 13 in 6-12 hours; or by a Nomad 20 in 5-6 hours.  A user with a smart phone and a couple of camera batteries that need to be charged daily may be well served by this solution (GoPro cameras can drain a lot of batteries if used extensively during the day).  On the other hand, higher capacity devices at much lower cost can be found elsewhere (see below).

10256904_18Goal Zero’s larger “Sherpa” battery recharging systems can recharge laptops and DSLR cameras.  The Sherpa 50 (1.2 lbs/544 g), for example, can recharge a laptop once (or a smart phone up to 7 times, or a GoPro up to 9 times) and has an optional AC inverter for charging through a regular wall plug.  The Sherpa 100 (1.9 lbs/864 g) has essentially twice the capacity than the 50.  The Sherpa 50 takes 6-12 hours to recharge using a Nomad 20.  The Sherpa 100 takes 10-20 hours to recharge using a Nomad 20.


A Nomad 13 (charging a Sherpa 50) and a Nomad 7 (charging a smart phone) strapped to the back of a safari wagon as we tear across the wild Serengeti.

A small, light and rugged device, our Sherpa 50 has kept us powered up on Kilimanjaro, on safari in the Serengeti, on Mt. Rainier and every year at MCamp.  Had the Sherpa 100 been available at the time we bought our Sherpa 50, we would have have opted for it instead for the added power.

Ideally, you want a solar recharging system that can give you a full charge in around 6-8 hours.  That’s a pretty ambitious thing to achieve (perhaps too ambitious for most people’s portable and affordable solar power needs).  To get a full charge in that amount of time takes the right combination of solar panels and the ability to track the sun as it moves across the sky to optimize the recharging process.

A system that gives you the power you need in 8-12 hours is the more attainable and affordable option. On days where the sun is hiding behind the clouds, you’ll have to conserve power and rely on your backup batteries.

A Nomad 7 recharging a Guide 10+ which is charging a smart phone connected to a portable speaker rocking beach music on a winter's day.

A Nomad 7 recharging a Guide 10+.

If your electronic devices can recharge through USB, you may not need a Sherpa 50/100 with an AC inverter.  However, recharging anything directly through USB will tie up your device during the process and may be slower than using a plug-in brick-style charger.

Most DSLR camera batteries require plug-in brick-style chargers. Sony’s Alpha line of mirror-less cameras, however, can be recharged directly via USB – a definite asset for off-the-grid adventuring.  You can also now purchase third-party USB-powered brick-style camera battery chargers that effectively eliminate the need for plug-in charging (see cold weather charging tip at bottom of page).

At MCamp we usually put our panels out on an east-facing slope beside the cabin around 7 am and then move them to a southwest-facing slope at noon.  The sun disappears behind the western mountains in the evening earlier than down on the coast so we usually bring the solar gear back inside around 7 pm.

In 2013, we paired a small two-panel Nomad 7 with a Goal Zero Guide 10+ and we paired a medium-sized two-panel Nomad 13 with a Sherpa 50.

In 2014, we substituted a Nexxtech 6,600 mAh powerpack that we bought at Radio Shack for the Guide 10+ since it was lighter and had a higher capacity (the Guide 10+ was only 2,300mAh).

In 2015, we substituted a PNY 10,400 mAh power packpny 1 we bought at Best Buy for $70 for the Nexxtech powerpack and have been super pleased with it so far. With that much pocketable recharging power, we can do multiple recharges of all our gear on a single charge of the powerpack (e.g., USB-rechargable camera batteries, smart phones, etc.).  This powerpack gives us far more capacity than the Goal Zero Venture 30 at about the same weight and bulk and at a significant cost savings.  The detailed digital display of your charging and usage status is an added bonus.  This power pack may be all you need for a couple of nights in the backcountry.

Note on power pack capacity:  In our experience, you should budget about 3,000 mAh per full smart phone recharge.   Accordingly, a 6,000 mAh device should fully recharge the average smart phone about twice.  Check the listed specs when purchasing to make sure you get a device suitable for your intended purpose.

DSC01281 a

Nomad 13 + 20 charging a Sherpa 50 high above Rogers Pass.

In 2015, we added a larger-sized three-panel Nomad 20 to our old Nomad 13 to supercharge our solar energy generation capacity.

Generating a combined 33 watts of solar power (these panels come with a built-in wire to connect them to each other), we now have the ability to recharge the Sherpa 50 in only 3-4 hours (this took all day before with the Nomad 13 on its own).  Should the weather be dodgy, we’ll have more flexibility than before with this system.

At MCamp15, we were delighted to find that the Nomad 13+20 combination fully recharged our Sherpa 50 by noon (usually drained the night before) giving us the benefit of being able to recharge some items during lunch and then put the system back out for the afternoon so it was fully charged again for the evening’s recharging needs.  The only upgrade I can image for this system might be to swap our Sherpa 50 for a Sherpa 100 – otherwise this system has all our recharging needs for a week in the mountains covered.

At MCamp16 (two weeks back-to-back) we had poor weather almost constantly (except for both week’s summit days 🙂 ) and couldn’t keep all our gear fully charged.  Snow, rain, and constant clouds hampered our ability to generate solar power.  A new power generation solution will have to be found for weeks like that (steam, wind, hydro?) or we’ll have to haul a massive battery like the GZ Yeti 400 or 1250 up the mountain.

Dscn5153 signed

Goal Zero Nomad 13 charging a Sherpa 50 (in the zippered rear compartment) at Shira Camp (12,000′) on Mt. Kilimanjaro.

All the Nomad portable solar panels have loops sewn around their perimeter so you can hang them wherever you want.  Some people hang the small Nomad 7 from their backpacks so they can charge while hiking.

So, what is the best system for you?

That will depend on the size and number of electronic devices you want to recharge and the size and weight of the system you want to lug around and, as always, your budget.

Check out Goal Zero’s website for more information (excellent comparison tables for panels and power packs).  They also package together panels and power packs as complete systems but don’t be afraid to mix and match to suit your individual needs.

Our experience has been that you will be better served by using the next size up in solar panel than the one bundled with the solar kits put together by Goal Zero (subject to whatever your limitations are with respect to packable size, weight and budget).

Don’t forget, this gear goes on sale at from time-to-time (we’ve bought most of our solar gear this way).  Be careful with Canadian vendors that sell this gear for ridiculous prices when compared to their retail price in the USA.  Use and as your guide for fair prices.

Basic Camera Battery Advice:

For cameras at MCamp, we recommend you carry at least one spare with you during the day on the mountain (most camera batteries will do a few hundred photos on one charge).

For GoPros at MCamp, we recommend you carry at least two or three spares during the day on the mountain (GoPros can chew through their batteries in less than an hour of use).

Recharging Camera Batteries in Extreme Cold Conditions:

Charging camera batteries in extreme cold is a challenge.  Camera batteries simply won’t recharge if they get too cold.  You need to recharge them inside a jacket or other warm space.  However, you can’t put your camera inside your jacket or it will fog up and be unusable.

20151202_142558To recharge camera batteries in sub-zero conditions , we’ve found an excellent solution:  This slim, light Vivitar USB-powered rapid battery charger* lets you charge two batteries (this particular model charges Sony Alpha mirror-less NP-FW50 batteries – other models are available to charge other camera batteries) with a pocketable powerpack (PNY 10,400 shown).  With this system you can comfortably recharge your spare batteries inside your jacket while continuing to use your camera!   Problem solved!

* Model no. VIV-QC-1043. Purchased from bundled with two spare batteries.


We accept no responsibility for loss or damage to participants’ personal property.

DSCN4473 a

Leave a comment

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Create a free website or blog at

%d bloggers like this: