October 13, 20241 yr Hi there After two tears improving a quite small installation, I enter my first winter in pure offgrid mode (France). I use a fairly simple technique : wood stove for heating and cooking ! Then I add lots of panels, especially on the ground, on the light spots on December 21 (they are currently on sale, not to mention the many new PVs with broken glass lying around waiting for destructive recycling). I am now aiming for 4 strings on an mppt rs450 : SE 45°, South 50°, South 15° (full power in summer + a little more watts during cloudy days in winter), SW 45°. VOC of 430v and 22a per string (be careful of polarity inversions, above 20a this mppt is no longer protected). This allows the series to be spaced apart without going into a PV cable section delirium. Very modest inverter so far: MPII 3000VA supplemented by a low-end inverter (which I limit to 3000w real) in 72v, on the scooter, rewired in neutral earth junction, supplying the AC IN, with a shunt on the switch of the 72v inverter which allows it to be switched on or off on Victron instruction. Which gives me a nominal power of 5.4 kWc with the low no-load consumption of the smallest MPII in the range. Comparative tests at the moment with an MPII 10000 lent by a neighbor friend (among other self-consumption and current calls in UPS to be checked). Until now my domestic battery being tiny (lifepo 4 16s 75ah DIY), I found the solution of limiting the battery charging power via its bms, while leaving the MPPT full throttle. To absorb the production I cause more or less heavy consumption, via the programming of the Victron equipment. It will clip hard in summer, but before that I will have covered almost everything that corresponds to a modern electrical consumption. In the hyper dark weeks of November/February, if the 1000w wind turbine does not manage to fill the gap, I still have the option of pumping electricity from the neighbor, with my 8kWh scooter. I see that there are pretty skilled members here, that should help, happy to join in ! Edited October 14, 20241 yr by Shortcut
October 13, 20241 yr Welcome to the forum. Lovely to be totally off grid, well done, and may you successfully go through your first winter. We are always interested to hear what setup you are using, inverter, panels, batteries, monitor software, etc, if you feel like sharing. 👍
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