Perry's Blog

Further Reading: 54 Day On-Track Review :: from the Bibbulmun Track.

The main reason we decided to purchase a solar charger was to give us greater flexibility whilst we're out walking. When we did the Great North Walk it felt like my pockets were awash with batteries, plus the quality of the battery you can purchase in out-of-the-way places is not great .

To be honest, we weren't initially looking at solar chargers; but after considering a SteriPen with the solar charger we realised that having the ability to charge whilst walking added a lot of benefits. And to our surprise there are quite a few solar chargers out there that could be used in a bushwalking situation. The good people at Multi-Powered Products were very helpful during our sussing; unfortunately we couldn't send our business their way as they had supply problems on the Fuse.

We eventually decided on the Voltaic Fuse because:

• It could charge all our battery sizes (though its many attachments)
• It came with it's own high capacity battery (means you can charge overnight)
• Well designed, tough construction
• Ability to charge from mains (if the sun fails)

Out of the Box
The Fuse is pretty easy to understand, but also comes with good instructions as well. We set it up in our front room that has a window facing the sun and were impressed how quickly the Fuse charged its battery to full.

There are a couple of lights on the Fuse, which don't mean the same thing... there is an external LED that indicates that the panels are generating electricity; and there are LEDs on the battery that indicate that electricity is being stored. Initially we were a little confused, but it quickly became obvious that even though the solar panels can generate electricty at quite low light levels there sometimes isn't enough to charge the battery.

Also the battery has a couple of different methods of showing how much charge it has: 1. When charging the LEDs light sequentially and 2. You can unplug it and power the battery on. During the testing in our sun room they definitely indicated different amounts at the same charge level: Jeff, the extremely helpful contact at Volaic, clarified in one of his emails:

>> Unfortunately, the lights when charging and on the button don't always match exactly.
>> We're trying to improve it, but it is an inexact science and the Voltage of the battery
>>(what is used to detect charge level) changes a lot depending on whether it is receiving a
>> charge or is under load.

> That makes sense, thanks. Would I be right in guessing that the lights when charging are
> the more accurate??

The opposite, the lights when pressing the charge indicator is probably slightly more accurate. Again, its not like a fuel gauge, the smarts the battery is using to judge level is not perfect (on my expensive Canon camera, I often see the same thing. It stays at full for a long time, goes to 3/4 and then drops very quickly to empty)

I also had to purchase a little USB AA/AAA battery charger and a charger for my Sanyo camera that connected to the Fuse using the car socket. Voltaic are working on their own AA/AAA charger that sounds like it will be more efficient than the USB variety. The Samsung connecter worked fine with our phone.

On the Track
We tested the Fuse on the Mittagong to Katoomba walk in preparation of the much longer walk of the Bibbulmun Track. I wanted to get a pretty accurate estimation of what the Fuse's ability to charge our batteries over an extended time was going to be.

This is our FUSE Track Log, the graphic is upside-down to match the text. The colour of the track indicates the weather: Blue == sunny; Light Grey == Scattered Clouds to Overcast; Dark Grey == Overcast; Darker Grey == Raining.

Day 1: Sunny Day

• Bracken Flat: topped up 4 AA from SteriPen

Day 2: Overcast
Day 3: Overcast

• Charged GPS Batteries overnight: fully charged by morning

Day 4: cloudy and overcast
Day 5: Sunny and scattered cloud

• Charged phone from Wollondilly to Yerranderie: Phone 1/5 bars to 4/5 bars

Day 6 (Rest Day): Sunny: No clouds

• Charged camera battery from nearly empty to full (11am - 3pm) on 12v panel setting.
• FUSE in full sun all day: internal battery charged from 1 light to 3 lights.
• Charged phone from 4/5 bars to full from 6pm - 7:15pm; FUSE battery drained to 1 light.

Day 7: Sunny with passing clouds, cloudy afternoon

• FUSE charged internal battery to 3 lights. Now sitting in full sun (1pm).
• SPOT reporting low batteries: change batteries and charge -
  * 2 AAA fully charged from 2:20 - 3:30pm
  * 1 AAA fully charged from 3:30 - 4:30pm
• FUSE Internal battery to 3 lights

Day 8: Mostly cloudy with some rain and little sun

• GPS AA batteries fully charged from 8:20am - 1:40pm
• FUSE Internal battery to 1 light flashing.
• FUSE charging internal battery from 1:40pm, finished day 1 light not flashing

Day 9: Scattered morning showers, then cloudy till scattered clouds over lunch, then overcast

• FUSE with 1 light at 1pm (Cox's River)
• Change camera battery
• FUSE charged to 2 lights.

Day 10: Overcast

• FUSE charged to 2 lights by midday (end of walk).

Well, that's interesting, but...
I don't think that the weather we had on the walk was particularly good for generating solar electricity (except for our rest day). Unfortunately the SteriPen we were testing on the same walk failed, so we didn't have the same battery requirements (the SteriPen uses 4 x AA batteries). It also meant that when I forgot to charge the GPS batteries I could use the unused SteriPen batteries .

The first 4 days of the walk we were under the technically "closed" canopy in Blatch's Pass (though it wasn't dense), also the cloud cover was pretty significant: all up I was impressed with how the Fuse went in such trying conditions. We were walking under cloudy or patchy skies most of the time, which meant that we tried to make sure the Fuse was in sun when it was available, especially during stops.

The first night, as a result of the SteriPen failing, I topped up the 4 x AA SteriPen batteries, although they hadn't been used very much. This was the only draw on the Fuse, so the internal battery would have been close to fully charged by Day 3.

Our GPS chews through two AA batteries each two days, so we had to swap them out and charge them at the end of Day 3. The Fuse offers a great benefit in that it can maximise the amount of charge gathered through the day and use the night to charge the batteries. Our two 2700 mAH batteries fully charged over night (Well, they probably finished in the wee hours of the morning, but we weren't awake to record that... the track was a lot harder than we'd imagined and we were exhausted each night ).

I'm guessing that the GPS batteries would have used half the Fuse's battery, so we would have started Day 4 at around 2/4 lights (<50%); Day 4 wasn't much chop for charging purposes, and on Day 5 we charged our Samsung phone from 1/5 bars to 4/5 bars in initially sunny conditions. We had the phone plugged into the battery at the same time as the battery was plugged into the solar panels. The Fuse battery must have ended up around 1/4 lights (<25%).

Our rest day at Yerranderie was a glorious sunny day and we had the Fuse out in the sun all the day. It fully charged our nearly empty camera battery, directly attached to the panels in 12V mode (this means the internal battery was not charging, it only had a couple of hours after 3pm to charge). In the evening the Fuse also topped up the phone, from 4/5 bars to full, and finished a busy day with 1/4 lights of charge left (<25%) to start the next day with.

Day 7 we set off on the second half of the walk with the Fuse at 1/4 lights of charge (<25%). The day started with passing clouds and became more cloudy as the afternoon wore on. The Fuse charged up to 3/4 lights (<75%) during the morning. That's about 50% of battery in just over 5 hours: That's great going as Voltaic say that the battery will take 6-7 hours to charge in good, direct light. That would indicate that on Day 7 the Fuse was charging around 70% of its optimum?

During the afternoon we charged 3 1,000 mAH AAA batteries (for the SPOT Messenger) with no net loss from the Fuse battery (The Fuse was charging at the same time as it was charging the batteries). Though we did need to remember to move the Fuse when shaddows again crept over it through the afternoon.

On the morning of Day 8 we had to charge the GPS batteries again, which took a little over 5 hours and drained the Fuse to 1/4 Flashing light (indicates very low battery). The day was pretty cloudy and rained a bit in the morning, so I'm not sure how much the Fuse actually would have been able to charge its internal battery during the walk. When we got to camp at 1:40pm we put the Fuse in as much sun as we could (it felt pretty watery by that stage), and it finished with 1/4 Lights charged (<25%).

Day 9 was very similar to the previous with lots of clouds and a bit of drizzle; consequently the internal battery was not registering any more charge by the time we reached the Coxs River at lunch time. Never-the-less, the sun was starting to poke its way through the clouds and we put a camera battery on to charge, and the Fuse finished the day on 2/4 lights of charge (<50%). Apart from the hour we took resting on the river bank, the rest of the day's walk was through dappled shade, which means that 1 hr of sun and 3 hr of dappled shade increased the battery by 25% (maybe one AA battery's worth?).

The last day was also overcast during the walk and didn't increase the charge in the battery at all as most of it was also under canopy.

Attaching it to the Pack
Voltaic have a number of videos demonstrating how to attach the Fuse to different packs, none of which resembled our packs . The Fuse comes with three straps (two x 1" and one x 3/4") and a series of clips. The system is extremely flexible, because our packs were full packs we needed to purchase another strap that could reach to the anchor points at the bottom of our packs.

When you're walking the orientation of the Fuse is obviously not going to be perfect (you're not walking away from the sun every minute of the day ). The extra strap we purchased is quite long, and this gives us added flexability to orient the Fuse toward the sun as we're walking along, either tight on the forward straps (to face forwards) or loose so that the fuse is angled further down the pack (either left or right).

Conclusions
Apart from the battery charging, let me start by stating that I am very impressed with the design and manufacture of the Fuse. The Fuse is an amazing piece of fancy technology, but it's also tough. We took it through 4 days of bush bashing, which included numerous tumbles; rain and drizzle; and it came through unscathed! This is not to say we weren't careful... we were, but you can only be so careful when you're exhausted and you're bush bashing through scrub and low branches.

Over the 9 days of walking and 1 rest day the Fuse, which started full and finished half-full, managed to charge:

• 3 x 1,000 mAH AAA batteries
• 4 x 2,700 mAH AA batteries
• 2 x 910 mHA NP-BG1 batteries
• 1 x Samsung phone

Because of the non-ideal situation we felt it was important to habitually put the Fuse into the sun when we'd stopped, and to align the Fuse the best you can when you're walking. This became second nature pretty quickly and was certainly not a hassle. It's important to maximise what sun you've got... I did say to Sandi at one point that I thought it would be better if she walked crab-like sideways down the track but I was only half joking as that's not really possible, and you have to just take the conditions as you find them.

Is it enough?
Well it was enough for this walk, and as stressed during the review, the weather was not very conducive to charging solar electricity. But I was encouraged by the experience of Day 7's morning that indicated that an average sunny day's walking would charge at around 70% Voltaic's optimum rate: about a full battery in ~10 hours.

Whether it will be enough for future walks will obviously depend on the weather and the walk. A lot will also depend on the solar penetration to the track you're walking on: bushwalking generally indicates the presence of bush -- which means shaddows. Much of this walk was through the dappled shade of tall trees, even when we weren't bush bashing.

I guess the walk could have been a weather disaster and either rained or been heavy cloud each day... and there's not much you can do about that.

So overall we're very happy with this purchase, it's performed well in much less than optimum conditions and has stood up to some punishing treatment on the track. We're very hopeful that it will enable our powered gadgets to keep working during the 2 months of the Bibbulmun Track.

Update: See 54 Day On-Track Review :: Voltaic FUSE for details of how the FUSE performed over the two months on the Bibbulmun Track.