My current solar / battery setup

Started by scarr, March 07, 2017, 08:29:17 AM

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Hi all, just a quick post to show and give a few thoughts on my current radio + power setup.

First of all - a list of the main equipment:

Yaesu FT817ND
Instapark Mercury 27W Folding Solar Panel
Genasun GV-5 MPPT Charge Controller
i-Tecc 12V 8Ah LiFePO4 Battery
Palm Morse Key
Cheap eBay watt meter ~€11
Headphones + various cables

Not pictured - my EFHW - it's currently outside!

Everything except the panel is packed into two cheap watertight plastic containers picked up from a local supermarket. I have additional padding, not shown, that goes into the containers. I intend to order a travel telescopic pole shortly. I could also fit more items e.g. ZM-2 tuner and digital interface. I threw the pictured kit on a weighing scales and it comes in around 4.3kg.

Obviously this is not a minimalist kit, but the purpose is to be able to move around between locations and be able to operate for an extended period across multiple bands with voice and CW independently of mains electricity. For me, this isn't so much about prepping but really about allowing flexibility - I move relatively often & I'm interested in operating portable, therefore it just makes a lot of sense to have this kind of setup!

The 817 requires no introduction, cost wise at least in Europe, it's still the most flexible for the price and for civilian kit it's relatively tough.
The panel, at this time of year is able to generate enough power to keep the battery topped off - more on that later.
The Genasun is small, lightweight and even better it is RF quiet!
The LiFePO4 battery is lightweight compared to SLA and even without solar power would keep the 817 going in a very busy transmit/receive duty cycle for hours and hours.

Regarding solar power - I'm located in Ireland at approx 53N and it is cloudy and rainy here a lot! In a more favourable location a 10W panel would probably be more than enough, but not here. On really cloudy winter days, even the 27w panel struggles. Today it's cloudy with a misty rain but the disk of the sun is visible - the battery was topped up to full capacity and the panel was outputting approx 5w which will keep the 817 going for RX indefinitely.

I believe the Instapark panels operate in series and therefore it's really important to make sure all panels are orientated in the same direction - having one even a little off can lead to a significant drop in power - think of it like having a dead battery in series. This can sometimes be hard to spot, so I strongly recommend that anyone using solar power with a panel like this, has a watt meter they can place into the circuit to observe what's happening.

This isn't the ultimate kit or anything, but so far, it works. I've built the kit slowly up over time and after a lot of reading.

Here are a few resources I've found extremely useful:


Great stuff Scarr.

I hear you about the 817.. I got the KX2 and was charged E300 in VAT and import charges  >:( The 817nd would have cost me E620.

The Genasun controllers are indeed excellent. I had two on my sailboat. I need to check out that solar panel because the 60W AllPower model I had in mind is a bit expensive. So I assume the Instapark has a 12V output? Hard to find... My 14W Choetec only has USB out. I can charge AA and 18650 cells, but being able to recharge bigger batteries would be nice. If i had a good capacity 12V gel cell like yours I could use it to charge my 24-29V Clansman batteries (20 NiCad cells, 5Ah).

I use LIPOS but I lost a few small 3S packs because I wasn't monitoring cell voltage closely enough. Once a cell goes much below 3V you might destroy the pack. Recharging LIPOS with a solar panel might prove troublesome, though i think Genasun makes the controllers as well. You won't get cell balancing, but it works for a few charges before you need to balance. I think I will get a 5Ah 3S LIPO for my KX2. Right now I use three 3000mAh 18650 cells. You can get them from discarded laptop batteries. I use two Nitecore UM-10 USB chargers with my Choetec solar panel...

Good choice on the ZM-2 as well. Although I mostly use the Elecraft T1 my ZM-2 doesn't require batteries and has a 50 Ohm bridge, but you know that...

I am now near Lille, north of France. We should try a contact some time...



March 07, 2017, 05:04:52 PM #2 Last Edit: March 07, 2017, 05:07:54 PM by scarr
A sked would be great gil - I'm sure we can organise something, maybe 40M in the early morning/evening?

Once I factored in the VAT, I gave up trying to justify the KX2/3. If I had the money, sure, but the sums didn't add up for my situation!

Yes the instapark has a cigarette lighter output - the voltage on it can be up to 17-18V, so you definitely need a charge controller. One thing I didn't show is the USB power meter & micro usb lead in the pocket of the solar panel. In addition to the cigarette lighter output on the panel there are two regulated 5V USB outputs, so it's possible to charge up a phone, tablet or backup 5V battery directly, which is a nice bonus.

I'm considering whether or not to strip the cigarette lighter socket and install more power poles, but haven't done it yet.

I did a lot of reading before deciding on the 4S2P LiFePO4 battery, it has a battery management system built in which should prevent me from killing it anytime soon. I'm going to scrawl some voltage readings on the side, but basically once it hits 12V the voltage will rapidly fall off. There's an argument for running the FT817 off a 3S2P as the rig can put out 5W and actually consumes less power overall, if you you feed it at around 10-11V.

The ZM-2 is a brilliant piece of kit, I've dropped mine, accidently fed it at 50W FM for a couple of seconds (don't ask) and it keeps on going. The versatility of being able to run everything from coax, to balanced, to random wires is just brilliant and the LED SWR meter is spot on. And yes, no batteries :)