Solar Power Update.

 Today I made the latest update to the solar power system for the shack.

The system now consists of a battery capacity total of 120Ah nominal, 4 pcs. 12V / 30Ah batteries.

Additionally, the 50W panel has been replaced with a 100W panel. The intention is adding another 100W panel, so the battery *can* be charged with a peak current of just under 20A. In the summer part of the year this should be sufficient to run some of the monitoring receiver systems 24/7. For the winter season a back up system using mains power in the low light solar periods should probably be added.

A higher current rated solar charge controller is also added. The previous one could only handle 10A charge current, the new one handles 20A, corresponding to 2x 100W solar panels. The system should operate within safe parameters. I do have the second 100W panel, so it is a matter of making a good mounting system.

At the moment this system powers my IC-705 fully, and more should be possible:

1) If the voltage drop from inside to the outdoor QO100 PA at the dish is not too high, the second use would be adding this with a switch in the shack. This is necessary as there is a current draw of somewhere about 100mA from the PA, as it is just using a WiFi ("8W") booster that has a DC/DC converter and is also active in "receive mode". It uses a very fast "HF-VOX" transmit-receive switch, so it is usable with SSB signals. The current power supply for this is using an extra DC/DC converter. This way the PA can be mounted in a smaller box closer to the feed antenna.

2) I located an adapter for cigarette lighter connector, so now it is possible to connect the hand-held 10m transceiver to use as a 24/7 monitor receiver for the FT8 frequency on 10m.

3) A small CW-only transceiver with <= 50W on the 80-40-30-20m can be used for mostly monitoring on one of those bands

4) I have crystals for 7074kHz (40m FT8) and 14074kHz (20m FT8) that could be used in simple receivers for monitoring those bands. Other options for building simple receivers for other bands are available.

5) Some "transistor radios" with SSB function can be used on other frequencies not covered by crystals available to me, and for some broadcast frequencies. This requires some extra voltage regulators as their voltage requirements vary from 2 - 4.5 - 6V, maybe others.

Long term I intend to make a separate solar power supply system for the QO-100 system, and a system for lighting, and maybe later some electrical tools.

In the past week I also found some, not too expensive, solar panels. 1 100W panel and 5 50W panels.

I should now have solar panels for peak power of up to a total of 600W. I intend to find more and looked a bit around. I could find some panels similar to the new ones I got this week in Germany, but as far as I can see, a "local" (I can drive there and pick up) has some 280W panels for 24V systems.

When I get those I will definitely need some high capacity batteries for storage. I have been looking into this, and the best solution - long term - looks like using LiFePO4 type batteries. Longer life time/more cycles possible than with lead-acid (gel) batteries so all-in-all a lower cost system. This does require better charge controllers, but I think it is worth it.

I am aware that it will not be possible to go completely off grid where I live, but I can, at least,  reduce the cost of energy in the longer term. A combination of mains and solar power will be the way to go here.