Updating our power system, pt. 1

During our trip so far, we had been lucky that any mechanical problems we had come across had been remedied fairly easily. We had had three separate holidays prior to our departure to really test what life would be like on the road. The first, a cold and damp trip to Scotland reassured us that we were capable of living together in a space of that size for two weeks without killing each other. It also proved our camper was capable of doing a long haul drive. 

The following summer we optimistically headed to the south of France to test how we would fair in a hotter climate and for an additional week. This was not quite such a happy affair and I still recall standing in a car park on the south coast, literally crying in frustration and on the verge of calling this whole big road trip off. One two many things had gone wrong at that point, but that’s a story for another day. 

Nevertheless, back in the UK I went about fixing the many issues that had arisen on our trip. Including a failing brake system and poorly designed coolant one. This meant that by the following easter, we were ready for a final trip a few months before our freight ship was due to leave. This last attempt only had two issues. The second arose on the last hundred miles of a thousand mile trip back to our house. The gearbox blew up 4th gear on the final stretch of the M25, leaving us to limp home in 3rd and think about just how expensive that would be later.

The other issue was our power system. At the time we ran a household fridge off two 120a.h. AGM batteries. These are charged via a voltage sensitive relay, with some help from a 150w solar panel on the roof. It became apparent after several cloudy days where we hadn’t driven that far, that this was not sufficient. We ended up needing to go to a campsite to hook our camper us as I couldn’t make a cup of tea and was consequently miserable.

It seemed that our leisure batteries were not up to the job. They weren’t old, but had been unfortunately drained completely which for any lead acid battery can be fatal. In preparation for our new trip, we forked out £300 for a new set up batteries and a battery protector to prevent this ever happening again. This system was fitted, and we also payed for a proper DC camping fridge, as this was less of a drain on the batteries as well as being a better use of our limited space.

Fast forward to Christmas and we are in a Texas Walmart car park with the rear cupboard emptied, getting a mechanic to test the batteries. We haven’t been able to turn on our cooker and the batteries appear to have lost their capacity already. Needless to say, I wasn’t impressed. The supplier was apologetic and happy to help if I could return the batteries. When I declined to post 60kg of acid across the Atlantic, we resigned ourselves to relying on our generator more. The mileage that we covered in the states gave us sufficient charge from our alternator to limp through a few more months and we adapted to life with limited power. Laptops were only charged during driving, the engine or generator was needed to start the cooker and we ran the fridge on its lowest setting.

A while later down in Baja, I got serious power envy when we met David and Katy and their lithium setup. It seemed that nearly everyone doing this long term off grid lifestyle was using lithium, great but it’s very expensive. That being the main reason I never fitted it in the first place. Shortly after telling someone that actually our cheap Chinese solar panel was surprisingly working ok, that gave up on us too. This left us with a pretty rubbish system. We attempted to recondition our batteries using the repair mode on our charger via the generator, which helped in the short term but it became clear that this was not going to work anymore. As we sat and watched our interior lighting flash in time to the cooker’s fuel pump it was decided. An upgrade was needed.

This brings us to our current quarantine camp. What better time to upgrade, we could order things for delivery. We had a secure place to work. We had the time to fit the system and most importantly we had access to the very large tool selection in the back of Bruno. So I dipped into the emergency fund, and picked out what we would get. I decided that I wanted to buy from a company, I wanted the security of a warranty and a reputable make rather than whatever was cheapest on eBay. I found that Renogy had some very competitively priced lithium batteries, but they wouldn’t deliver them to Mexico as they are a hazardous material. There were other shipping companies, but the import tax alone is 16% before shipping costs, which ended up with a cost of around $600 for postage. This was a bit of a non starter, and then Hanno mentioned the name of a supplier in Mexico mainland who stock Victron. A little research and I was sold. The batteries were reasonable priced and delivery within the same country was not a problem. Happy to order a new set up batteries here I also decided to get a battery to battery charger and a battery monitor. Lithium really needs a proper monitoring system, as the voltage does not give a proper indication of charge and a B2B charger is nice as it allows a full charge from the alternator when driving, something that is not achievable with a split charge circuit.

This was all great. The last sticking point was the solar panels. There wasn’t much in the way of flexible panels available in Mexico, there not being much of a market for them here. I could get them posted from America but this was pricey. Our friends had bought a new solid panel when their flexible panels had also failed (another common theme among long term travellers), from the local shop. They said the panel actually exceeded its own specifications, basically unheard from flexible panels which consistently seem to under deliver. Undoubtedly, solid panels are better but fitting one to Ruby was another matter. It would have to go on our pop top, adding an extra 30kg of weight. We would have to update out gas struts and buy a new charge controller. This sounds like a lot of extra faff and cost, but solid panels are cheaper. This one was also local so there would be not delivery charges which are high on solar panels. All in all, it meant that for an extra two hundred pounds or so, we could have a 405w system, rather than 225w. We would never run out of power again!!

This was all very exciting, so I placed a rather expensive order with the company in mainland Mexico who would be sending me three 60a.h. lithium batteries, a new charge controller and B2B charger and a battery monitor. This left us with the solar panel.

We arranged to pick it up in town and after test fitting our friends one in the back of the van, set off to collect it. It was rather big, a standard size of 1m x 2m. We managed to get it in the back of Ruby and safely got it back down the increasingly bad dirt road.

We now need to build a framework to mount it on the roof. Another trip to La Paz, and I managed to buy the necessary materials.

The idea was simple enough, a straightforward frame that would allow us to store our surfboards under the panel. We had previously stored them on top of the old panel as it didn’t work anyway, but this was obviously no longer an option. 

We debated how to fix this on. Clearly bolting it one was probably the strongest but it did mean that we would have holes in the pop top and they could potentially leak. Also if we later removed it, we’d still have holes. Hanno and Kiki had glued their roof rack on, and after dubiously looking at the specifications for the adhesive glue they had used it looked like it really would hold that much weight. At least we didn’t have to worry about wind resistance, as the roof box would still be higher. 

To buy this special glue, we had to go to an expensive marine shop in La Paz which had no prices on any of its products. Presumably to prevent heart attacks from any potential clientele. It also sold some heavy duty battery cable which would be necessary when fitting the new batteries. We would be swapping from two batteries to three and lithium does not use battery connectors like lead acid, preferring just a simpler bolt on terminal. I was pretty happy that I had managed to find everything I needed in shop, sometimes it can be hard to buy specific things here. What was not so pleasing was the price. A two metres of wire and some connectors, alongside one tube of silicone adhesive cost an eye watering £75.

Fortunately, we broke even a little later when I managed to get the six metres of heavy duty aluminium angle I needed for only £25. Swings and roundabouts. I now had everything I needed to install the new system when it arrived, and in the meantime we could begin fitting the new panel. 

One incredibly hot day at the camp, we began. The first job was to get the old panel off the roof, which had been enthusiastically glued down by trigger happy previous student armed with an entire tube of silicone. After sometime, I got the old panel off. It was relocated to the campsite kitchen to function as a wipeable table top.

Both Lee and I spent several hours cleaning off the remaining silicone. Regular breaks were required as it was incredibly warm and the roof was too hot to lean on. A day later, and we were ready to start fabricating our new rack system.

We decided to build the rack onto the panel on the ground, and then lift it up and glue it to the roof as a whole. This would make sure that everything lined up perfectly. We cut the two metre long strips that would run down the length of the van first, and then the rest of the aluminium made four upright sections that would bolt on the the strips glued to the roof and the panel. 

It was hard to gauge the correct height for these uprights as we needed them to clear the surfboard once on the roof, but the roof itself is curved making it hard to measure. We made them on the big side to be safe, we could always cut them down later. We also made it so that you could lift the panel up and slide the surfboards underneath. 

After all four of us managed to haul it onto the roof for a test fit, it was clear that we could lower the height of the panel by a good few inches, making it look a little less alien stuck up there on the roof. So we did some adjustments and bolted it all together. After prepping the roof and the metal, we were ready to stick it on. 

Again it was another hot day, according to the instructions on the glue we had 15 minutes of working time at 30 degrees. It wasn’t quite this hot, and we had been blessed with a cloudy day but it still meant we were definitely under a bit of time related pressure to glue the frame quickly and accurately. All four of us helped to lift and glue the aluminium angle in place, and soon we had used all our tube of expensive glue up and the frame was fixed. It would need a tidy up with some cheap silicone when it was dry, but we now nearly three times the solar power we previously had.

Having a 400w panel was great, but it turns out the solar controller I have is only a 10A controller, not 20A as I previously thought. This means that we couldn’t use most of our new power until the other parts arrive. It still showed how much our previous panels fell short of their rated spec though, as the next day we got a consistent 10 amps of charge current from about 9am till 7pm, something we had never had before even with our supposed 300w flexible panels. Now we just had to wait for the rest of the system to arrive…

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