Rigid solar panels - here we go
As concluded in our previous post Flexible solar panels - second season of use update our power audit has been put to the test in the challenging conditions of the Mediterranean summer and the conclusion was very simple although our three 180 watts flexible solar panels provided for a lot of our power needs with the addition of occasional motoring from place to place (dropping and lifting anchor) and the use of our petrol generator when the sun exposure was not enough, the reality is they cannot provide us with the power that we want to be able to run our lifestyle.
They produce around 2 KWh a day and that might suit lots of boats but we want a lot more. It’s not a matter of necessity it’s a personal choice.
We believe this point has come, about nine months ago we started a discussion in several Facebook groups related with the sailing community about the latest and greatest panels around and as a result, we had set our minds on 3 models.
Nothing that surprised us, we knew what we were getting when we bought them and since we didn’t have anything to lose we decided to do an experiment to try and fix them and see if we could extend their life.
Their condition did in fact improved from that state but we are still producing 0.5 kWh less than their original output and we do need a much higher power input.
We believe this point has come, about nine months ago we started a discussion in several Facebook groups related with the sailing community about the latest and greatest panels around and as a result, we had set our minds on 3 Sunpower X22 360 watt solar panels, several of our connections within the community had purchased them and were quite happy. With three of these high spec panels we would have 1080 watts installed and a better efficiency rate than with flexible panels, with this installed capacity we think we can eliminate the need to run a generator and provide enough solar to provide all our homes needs including heating water.
It was now time to pause and consider our options and installation methods.
Because we finished our 2018 season in Tunisia the purchase of the panels was put on hold due to the difficulties on getting them at our winter base for the year. With the approach of the beginning of the new season, we contacted the supplier once again for an updated cost and were surprised with the considerable drop of the price per watt for the same panel model we had inquired months earlier. At the same time, they already had an even more powerful model that would supersede the one we were looking for, and with an even better price.
But because we don’t really have a home base to return to where we can have things delivered and don’t stay long in the same place, arranging for items to be delivered is a great difficulty for us, so once again the purchase was delayed not being sure we could have the panels delivered in a marina for example in Sicily without forcing us to stay there a long time waiting for them.
The new plan was to have the panels delivered in Trieste, Italy at the house of a relative. Our plan was to go to Croatia for the summer season anyway so it would be a small detour to go collect the panels up north without having to stay bound to a marina waiting for the actual delivery.
As we started our way up the Adriatic towards Croatia and then further north to Trieste where we would have the panels delivered, we tried to finalise the details for the purchase. At that moment we found that Sunpower had released a panel with new technology, the Maxeon Max 3 400 watts panel for the same or a slightly better price than the panels we had been keeping an eye on for the previous six months.
Wow, now that’s real power and a game changer for us at 1200 watts, we considered it for about two weeks, when we went to order them we found that the supplier had already run out of stock, damn we missed out the opportunity and the option was to settle with 390-watt panels.
A bit disappointed we decided that it was not possible this was the only supplier in the region for those panels so we did a bit more research on other brands at the same level and started to track down new suppliers. To our surprise, we found an alternative that provided us with a technology we hadn’t considered before and that the SunPower panels did not provide.
We found the new LG390N2T-A5 panel, a 390-watt panel with BiFacial technology, that allows sunlight to be collected from the front face but also the back face. That could allow us to capture up to 30% more power, a whopping potential of 507 watts a panel or a total possible of 1521 watts for a 3-panel solar array.
These panels are different from the ones we were previously considering in many details, built with a bigger cell made with less boron these panels supposedly suffer less degradation, the cells connected by a round bar that distributes the power more efficiently also means the panels are less affected by shading, all backed by an LG 25 year warranty.
We decided to purchase these panels not only because of the technology but also because with this alternate supplier we were about to save more than 30% from the original SunPower panels price, very impressive indeed.
The LG panels are slightly heavier than the Sunpower by 3.5kg per panel and the size is a different proportion 1024mm x 2065mm instead of 1046mm x 1559mm but we feel we can make it work above the bimini.
So congratulations to us we are now going to hopefully be completely power independent all due to our upgraded solar system.
Now the fun part will be installing them, connecting it up to our Victron system and watch them work over the next months and years.