Daniel, the ‘ultimate scrounger’ was able to find a pallet load of 145W solar panels @ E75/ panel. This is about 1/2 the normal price for solar panels. I know I would have preferred 300 Watt panels, but we will just offerup some more deck space for future energy needs.
The Voc is pretty high 87 V, so we need to make sure the MPPT has a high enough voltage.
Since the Voc is so high if we put them im series we would need for just 2 an max voltage of 174V, or with 3 of 261V. Victrons MPPT start at 75, 100, 150 and 250. But with 3 in series we go over the 250V, so easiest all panels parallel, which will result in 87V max and with 24 V as battery, a Imax of 36.25 Amps (6 * 145 W panels gives 870 watt > 870/24=36.25 ) Realistically it will be below the 36 Amps. So that leaves us with the Victron MPPT 100/30 (max 880 W ) or 100/50 (max 1440W) . The 100/30 is about $202 the 100/50 is about $300. So we will go with the mppt_100_30
The Mppt will be connected to the batteries directly, and connected to the VenusGX. (Once it comes …it was supposed to arrive Q4 2016, not it is slated Q2 2017, until that time we can grab the CCGX from Serenity, with the GP and use that)
So we got to the point of putting the 6 panels on. In the mean time Daniel found 4 solar_panel_yingli_panda_yl260c-30b Watt panels, who could be fitted easier. Because of the low Vmp (30.8 V) we placed two in series and these two in parallel. To mount them we added a 20 mm thick neoprene cell rubber adhesive strip to the long sides of the panels. We made some aluminum strips to mount them all together.
Marc cutting strips picture
On the boat in the US I had bought the special attachment clamps, but here we opted for some self made aluminum strips, to mount two panels together. After mounting the strips on the long sides of the panels, we added the foam strip. and just laid the panels on the pilot house roof. ON a later date we will mount the outside strips through the roof
Marc making aluminum strips to keep them into place
Here Daniel is adding some extra caulk to the cable passthrough
The panels are connected to a Victron MPPT 100/30 and then directly to the batteries.
Here is a view from the Victron CCGX showing the solar power on a sunny day 720 Watts
With the 4 panels being flat 720 watt is a good efficiency for 1000 W solar panels. If we have 4- 5 hrs we will get 3 KW/day, which is more than sufficient to be self sustainable.