Idea Box: A Small Solar Lighting System Etc. for the Bedroom.

 Overview:

Using some GEL batteries for providing light in the bedroom. Using small panels mounted to the "top window panes", and a simple charge controller, e.g. the 10A model I already have. Tests of small solar panels will have to be made to see if they can provide sufficient power for the night light, as well as power for MP3 player(s) and amplifier(s), so some audio (e.g. audio books) can be played in there. If necessary, an externally mounted solar panel can be used, but a fully indoor system is preferred.

If this works a similar system can be used in the living room. Both rooms have windows facing South, so it might be possible.

A bit of testing and design:

All this should be tested, (and possibly used) until a more permanent system can be made for solar powering more of the house, e.g. a solar powered audio player system. 

A video player system will require more power, but this can be a start before more solar (entertainment) becomes available in the house.

Bedroom system:

Here is an idea for a small solar power system for the bedroom. As you can imagine, the power requirements for bedroom lighting are not very large, so I would like to add a low power "entertainment system", just for audio, some very low level "orientation lighting" with short LED strips, a "reading light", and a tiny audio system with one of my MP3 players, so I can listen to audio books when resting there, and a charger for the mobile devices, such as phone, tablets and e-readers. I suspect that I can keep the daily energy consumption down to some 10s of Wh, so I need to make myself a budget. 

First I will have to test the energy consumption of the different devices I have, then calculate the needed overhead of power, e.g. make an estimate of the number of sun-less days I need to have energy storage for.

I finally located some small panels I have. They are so-called 20W ones. I need to test them to see how it works in full sunlight (open circuit voltage and short circuit current test), and how they they work behind my windows I will try to make the system with some of those. I have 9 of them, so I should get sufficient power for some low light and some audio in the bedroom, probably using 3 or 4 of them. Even if they are only 10 - 15W the system should work. An effective 40W will likely be sufficient for the bedroom system.

Somewhere I should have a box of single cells and very small panels that I should test and see if I can get sufficient power out of them for similar systems

For similar systems I might also try to salvage some small panels from worn-out (discarded) solar-power-packs as well.

If I consider the idle current draw for the charge controller too high, I have to make a simple one myself, or a switching circuit for disconnecting it when there is no sunlight. 

If I get satisfied with this system I may make other low power systems for other uses, e.g. a weather station with remote sensing and rechargeable batteries as power supply.

Let this be the first test ...

Es on 10m, 6m and 4m.

 The sporadic E season seemed to start a bit slow this year.

OK, I was away for a week around 3. June, so I have probably missed several openings.

Now I am back, and the activity has got going again.

In my 5W challenge I have worked a few dozen QSOs on 10 and 6m. The QSOs worked in the challenge just passed 200, so I am fully on track. On 4m I worked a single station with 25W, and could probably have done more with more activity.

The solar activity has been a bit lower after the quite strong activity we have had in April and May. The SFI just dropped below 100 for a few days, but now it is coming up again. There was one spotless day (the first this year, I think). The geomagnetic field has been rather quiet, as there have been no significant flares or coronal holes to send any substantial solar wind in the direction of Earth.

The solar power for the shack is still insufficient for the use of all the radios I want to make use of in this time when propagation monitoring is quite interesting for the high HF bands and the VHF bands. More battery capacity as well as solar panels need to be connected, and some low power monitor receiving equipment is also needed.

There are now 8  LiFePO4 cells ready to build a battery for the lab I have upstairs. All have been charged and balanced with the small solar power system for the lab, and I still have 20 cells to prepare for more energy storage.

What I need for making a good, solid battery (12V - 200Ah) will be some bus bars (heavy duty copper connections between the cells) Right now I will test the system with a somewhat lower load, and therefore I *can* use some heavy duty wire for the connections, but I will have to locate or make some of the bus bars if I want to use the battery efficiently for powering the main part of the lab. 

When ready the lab solar power system should be able to deliver/store 12V - 200Ah and shared with the 12V system, an added 12V -> 24V for use with soldering iron and computer. I also have a 100W inverter, so it should be possible to power the spectrum analyzer and the TRX test set, plus other 230V test equipment for limited periods. This system should also be used for the charging/balancing of the remaining LiFePO4 cells.

Also, I noticed a substantial amount of switching noise from my primitive switch mode charger for the single cells, so I will have to limit the charging/balancing of the remaining cell to the night time, then get some EMI filtering connected as soon as possible.