Now that with my #atlanticloop project the cat is out of the bag, I tackle the huge question marks which are popping up frequently in terms of technology, equipment and such. One of the big, big questions is: “How can I make sure that I have enough energy to run auto pilot and nav-systems aboard my electric-powered boat during a long transatlantic voyage? Well, solar is a big thing of course and as you may know I had already started to work on this.

What´s in the box?

How great was my excitement when DHL rang at the door and handed me a big box: The solar modules by Italian company Solbian arrived! My boat is equipped with a small 50 Wp-module that is recharging the built-in Li-Ion consumer battery. On the other hand, my boat is powered by the Torqeedo Cruise 4.0 engine (electric, of course) and the energy is provided by the huge Torqeedo WH 48-5000 battery. I decided that 50 Wp isn´t enough and worked with Solbian to replace the small 50 Wp with a bigger one. Now the module arrived. Let´s have a look then …

Unboxing the Solbian Solar Panels

The Solbian modules I went for are of the SP-series by Solbian. The company offers four series of which the SP is characterized as delivering “power at the highest level” – exactly what I want. The cells are made in Italy (no China-product) and come with a 5 year warranty. The module in which the cells are integrated can be ordered to be clear or pigmented in black, of which I chose the latter.

Solbian´s SP-series for enhanced power generation

The modules are always custom-made according to provided measurements and possible changes done upon fitting of an 1:1 paper-model that will be printed and sent to the clients prior production. I have written a whole article on this procedure which you may read here. Now having the modules at home in reality feels great. The feel of the surface and whole finishing quality lives up to the product claim of Solbian and its price. It is absolutely worth it, I´d say.

Quite a big module though …

As for my boat, the module is devided into two separate panels which are much more convenient to transport and work with. I put both together and have them laid out on the floor of my flat and suddenly realized how big this whole venture really is. I cannot wait to have them installed …

Fitting of the Solar Panels

It has been a good thing to take out GEKKO of the water so soon since work is now starting to be overwhelming with the first boat shows taking place indeed after 2 years of Covid-craziness and also lots of late-summer deliveries eat away my time. No spare time left for any private sailing, which is sad, of course, but on the other hand I can concentrate on upgrading the boat step by step. In the yard of my company on one afternoon, I took the panels with me and climbed onto the boat. Let´s see how it all looks like and feels like when put on the very boat.

GEKKO is back in the shed: Let´s roll!

And guess what? It fits and looks awesome! I congratulate myself of opting for the black-colored panels which is giving the boat a kind of mean look, fitting the overall racy character of the Seascape 27. The panels fit perfectly and there is no margin or tolerance whatsoever. I especially love the non-skid surface and the soft/hard feel of the panel material – especially the area in front of the mast may be stepped upon when reefing the main sail, so I need to have a very rigid surface here.

Fits perfectly – looks so neat!

In the end I am very, very satisfied with Solbian´s work and advice during the project phase and I am happy to have bought their custom-fitted product rather than opting for rectangular standard solar modules which may fit or may not fit. But looking at the solar panel on my boat I kind of felt that this may not be enough …

Some more calculations

You see, after I decided to replace the standard 50 Wp-solar module installed by the yard with a 140 Wp-panel, it turned out to deliver “only” 138 Wp after fitting of the 1:1 paper-model of the panel. Now, with long haul sailing trips in mind I am indeed a bit worried that these 138 Wp won´t be enough to sufficiently (fast) reload the current taken off of the batteries. The boat will be utilizing navigation equipment and – most (important) of all – the autopilot and this is draining the battery so much that I need a solution here. And 138 Wp isn´t going to solve this problem. So I asked Solbian what to do.

50 Wp versus 138 Wp

Well, there is always more space to fill. And the same way the replacement of the small 50 Wp-module with 138 Wp is making a huge difference, there may be some more areas on the boat which could be utilized to squeeze in more photovoltaic cells to my boat. I identified the sides of the coachroof which are some 2.50 metres long and between 20 and 50 cm high. Wouldn´t that be a solution to the increasing energy demand? Let´s look …

Making a gauge model of cardboard

Speaking with Solbian Germany CEO Michael Körner he encouraged me to make a gauge model of the area so that he might be able to come up with a construction and solution. Another Sunday afternoon I opened the yard and climbed onto my boat, fitting a thin wallpaper to the boat´s side, made a cardboard spacer to have an exact outline measured from the deck and began working.

Working flawless from the start

The paper-gauge was ready in half an hour and looked awesome. I then went to the already finished solar-panel to make a small cardboard-gauge of a single solar-cell to see where the available area would be too small to fit a cell. In the end, I was able to fit 18 cells on my gauge with a possible 19th cell. That should deliver 50 to 55 Wp, I thought and went down to the floor where I transferred the paper-measurements onto cardboard.

Available area vs. needed space by a solar cell

It was a bit disappointing to be honest that the available area turned out to be that small, I was hoping for 60 or maybe 70 Wp to either side, but anyway, much better than just rely on the one panel. That is because shadows are a real problem on sailboats: Depending on where the sails are in relation to the sun there will be up to 100 % shading on the solar panels by the sails and as such, no matter how many solar cells I can fit to the panel – if they are in the shadows, no current will flow.

18 to 19 cells should be possible …

By utilizing both sides of the cabin superstructure the hope is that at least one of them will be shown upon by the sun undisturbed. So, at anchor, for example, the sun will come up in the East, shining on one side and the roof, wander to the high noon-position shining on all three panels and set to the West, again, shining on at least two main panels. After I finished the cardboard model I handed it over to Michael, who – at the same day! – came up with a digitalized version.

200 Wp at any (perfect) moment: Super upgrade!

And again I am amazed by the apparent ease of the work bringing such a clarity into a complex matter: Solbian´s suggestion is to again fit two modules of 39 and 23 Wp, adding up to 62 Wp for each side: Much more than I had expected! Fitting 19 cells this concept git its instant approval from my side of course.

Plan by Solbian, 62 Wp on either side!

Now, imagining sailing on GEKKO and – for that matter – having the sun to windward, that would mean that at any given moment the main panels on the roof and one of the sides will produce 200 Wp constantly, which is great. So what next? Apart from the 1:1 cardboard models I am waiting for now, I will have to add two more solar-chargers to the equipment list. I am also figuring out how to connect the Torqeedo battery to the consumer battery so that the big one charges the small one. This would be perfect since I wouldn´t have to re-wire all current consumers to the big powerhouse.

Will look awesome – and do good!

I can´t wait to see the new panels arrive and fit them to the boat! The task is now a bit more complicated but I am sure we will have it installed, up and running before this winter. Torqeedo is also involved in this project as I was able to secure a direct contact to a person within the company who works as battery developer, Solbian is there to guide me as well. What an exciting project!


You may be interested in reading these articles too:

All solar-power related postings here

My first impressions on running electric

Sailing solo first time