Minerva10210

If some of you guys are interested, check this page out on facebrick. A few of us locals who enjoy the old tech https://www.facebook.com/groups/vintagecomputingsa I have a fair few old machines floating about at home, starting with the 8bit machines of the likes mentioned here - Vic20, C64, Speccy's - and then up from there into the 8088/286/386 etc machines.

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I am looking at a Multiplus II btw. Have a Carlo gavazzi already, and have a rpi running Venus. So that's sorted. Does one need Batts?

Hey guys. So a thought occurred to me. My plans are still to go with a full Victron/Pylontech ESS system in future, but I cannot get there money wise just yet. I can however potentially buy a 3kva Multi and say 4 panels now. Would this be sufficient to carry at least base load of 500-ish W during the day? If not, what is the bare minimum setup that will help save a bit during the day when the sun shines?

Wow, interesting discussion. I was wondering about this idea a while ago, even though I am still in the planning stage. I was trying to figure what stage 1, and expanding to stage 2,3..etc would look like ultimately. Seems I will win in one place, having my largest roof space where I would be able to fit 12-15panels less than 5* from North, but lose slightly then by only having a smaller East spot to add panels, but no West side that I can work with - bummer!

Forgot to mention, a 12led string like that pulls about 170mA, so not bad considering the amount of light. In the bathroom or passage I will only run 6leds, so <100mA. For the 5 areas I have allocated these so far, I am pulling less than 1A, so with my current 80odd Ah battery bank, that should do swimmingly (y)

So the politics aside (but not forgetting about it as it is a cluster f) I have started with getting something going as a start. Got a few of the 12v strip lights from the local China mall for R35 ea or thereabouts. Got warm and cool white LEDs, made a bit of mix to get better colour to my taste. Not sure if the pics are going to get the idea across due to automatic light sensing and the like, but anyhoo. The original fitting, my hillbilly light, and a ”closeup".

Thanks for the replies guys. So I already have a ET112 running, was my first step in trying to see where and how my energy usage happens. I have a few months worth of data already. Already running a EV tube geyser, and a gas hob. So some steps have already been taken. Working on the family habits is slow going, especially with a toddler who will leave a trail of lights down to the other end of the house to go to the bathroom, but conveniently forgets to switch off on the way back RE the R/$ yeah, noticed that 😐 would honestly love to put in now and reap the benefits, both from a saving on outlay + ongoing basis, but alas, just cannot make it happen now. Think I may just do the China-mall 12V lights all over as a start for now.

Hey guys So I am in a predicament of some sorts, and have itchy fingers. Ultimately, I am just about mind-made-up of what my ultimate setup is going to be - Multiplus grid tied, 12-15 panels, 2x pylons. The predicament is that I will only be able to put funds towards this around April/May 2020, so still some time away. I do however have the following stuffs floating around at home already 2x 10w 12v solarwind panels, random 20a 12/24v pwm charge controller, 12v 120w inverter (that is probably at least 18 years old), 15x 7.2AH batteries. So as per the title, is there anything productive I could do with this? I was thinking of putting some China mall special 12v LED light strips throughout the house, replacing all my 220v lights essentially - other than outside perimeter/security lights. I am however not sure the 20w worth of panels are going to be enough to ensure decent charging of the batteries. Should I then look at getting say a 80-100w panel, and be done with it? Or should I look at adding a newer, more efficent (say 300w-500w) inverter, and then run my alarm system/fence energiser/lights off the unit and thus "saving" on the 20 or so units from eskom on a monthly basis, and have an "emergency" backup system in place so to say? Or do I shelve the idea, and just save the R1000 for my big/proper setup come next year?

Thanks guys, appreciate the input 👍🏼

Hey guys What should be a straight forward question, is giving me a bit of a tickle. This is really only out of interest really, but is applicable I reckon. What exactly constitutes a "battery cycle"? I know that one should only use different cell type technologies to differing states of charge, which may influence this question's answer. If a LiFePo4 is usable to 10% SOC, that then constitutes 1 cycle obviously. What about 90%, or 40% etc? Should one see anything more than 25% used as a full cycle in this case? Then what about Lead Acid? only recommended to use down to 70% SOC (if I recall correctly), so again, using the above example, if one gets down to 90%, or 80, or the "depleted" 70%, where does one count as cycles=n+1 ? Secondly, on lead acid, from what I recall reading at some stage is that one wants the SOC to be brought back to 100% ASAP, as a LA battery does not do well to be in a discharged state for extended periods of time. But should one worry about 100% SOC, or depleting 1 cycle if you ultimately only used it down to 95% the previous cycle? I am running a "toy" setup at home currently, just as a proof of concept, and it is actually working quite nicely, even if it is only 3x 7.2AH batteries, with a 20A PWM charge controller, and a 30w china mall special panel running 4 lights throughout the house on a daily basis. I do still want to know how to treat the batteries to ensure best results.

I have used my C-tek for quite a few years, but was used for car batteries. It is only now that I am getting into the solar stuffs. I have found that standard car batteries a-la Willard, Sabat, Varta etc usually easily given quite a decent life extension. The 7Ah "alarm system" batteries however usually don't give such good results.

I am ever so slightly dissapoint 😕 Which one do you now trust?

Hold on, I think I may have the Azimuth angle in wrong there, I was assuming North as 0*, and I now see they seem to be basing their calcs by default to be Northern Hemisphere - so my input might be out by 180*

Umm, ok, so I'm confused again. I have seen both the calculators posted above before, and have made some notes to try and optimize my setup once I am able to get to the buy and install point. Anyways, I was under the impression that my roof at 26* tilt, and approx 5* azimuth was quite good for an all-round setup. However, I've just played a bit with the "JRC" calculator a bit more just out of interest, and used the "optimize slope" calculation on the site. Apparently 1* tilt is the best according to the calculator? Calc1 is the one off the solarhandbook's page, calc2 is the calculated 1* tilt, calc3 is using the same angle as recommended as per solarhandbook's page's result.