Watch on YouTube: https://www.youtube.com/watch?v=zjl9RXeMPr4
YouTube Channel Powered By DIY Solar - The Tour!
Introduction
Since August of last year I’ve been running this YouTube channel entirely on a DIY solar setup that I built. It consists of 480W of solar panels, a Renogy Rover 40A MPPT charge controller, 80Ah (1kWh) of LiFePO4 batteries, and an EcoFlow RIVER 2 PRO portable power station.
But how did I build it all as a complete solar beginner? Can it power all of my filming and editing equipment, tools, and all of the retro computers and consoles that I feature on my channel?
Let’s take a look and find out!
Script
I’ve been running this little retro computing / gaming channel pretty much entirely on solar power for around the past 8 months - including the winter - and I’ve had a few people ask me over that time how it all works, how long it will take to pay for itself if at all, what I can actually run on a setup like this and for how long, and maybe if something similar to this might be useful for them. So I thought I’d put together a video explaining it all.
So let’s start at the panels themselves. The window to the room that you just saw is just there, and out on this flat roof on some basic wooden frames that I put together and anchored to the wall there, I have 480W worth of solar panels made by a company called Eco-Worthy.
These panels are angled at 48 degrees - I was actually aiming for 52.5 which is my latitude here but it’s close enough - and the back wall of the house is south west facing at an angle of only 23 degrees off of due south, which would be the ideal, so again, that’s close enough.
It turns out they work great in this spot - I’ve seen a peak of over 390W back in August. Bear in mind that the rated output of 480W is in ideal conditions which we’ll never get here in the UK, and mainly there to serve as a basis for comparison between different panels, but I’m hoping I can top 400 in the height of summer so watch this space.
They are shaded by my neighbour’s house first thing in the morning, coming into full sun at about 10ish, and in the winter they’re partially shaded by my rear neighbour’s trees as the sun is so low in the sky, but that can’t really be helped without putting them up on the actual roof, and generally we’re really lucky with the sun here, and they do still generate a useful amount of power even when they’re not in full sun.
The solar panels are wired together in two banks of two, and with them being 12V panels that means I’m running a 24V system. The benefit of this over 12V is that there’s only half the current running through the wires which is safer, and also as my batteries are 12V, it should be more efficient as far as the charge controller is concerned as it has that overhead to work with, and I’ll get into the charge controller in a second.
They’re all wired up using industry standard MC4 connectors and 12AWG wire, which is what came with the kit. That should be safe for up to 20A of current, which - if my maths is correct which it might not be - happens to be the absolute theoretical maximum that this setup can put out. I’d like to upgrade this wiring and fit a solar combiner, which is a box with built-in circuit breakers and a switch to isolate the panels, and it’s probably something I’ll do as summer approaches as these will be pumping out a lot more power and it’ll give me a bigger margin for safety.
For now I have 10A inline fuses on each panel, which will protect them and the wiring in the event of a short circuit - if one panel failed to a dead short then theoretically the other 3 could all feed into it and blow something up which the fuse will prevent.
These don’t have blocking diodes because there’s not much chance of any individual panel being shaded apart from very briefly first thing in the morning, but the panels do have built-in bypass diodes. The diode stuff is all a bit outside of the scope of this video though so I’ll link some more info on that down below if you’re interested and modern panels of this size will generally come with bypass diodes built in as standard.
And now is a good point to make it very clear that I’m far from an expert in all this - this is just a tour of my own setup so please do your own research if you’re looking to design a similar system for your own purposes - again there are some links down below that should help.
So, the wires come through an existing air vent into this Renogy Rover 40A MPPT charge controller. In the simplest terms, this takes the power coming from the panels and uses it to charge the batteries, which you’ll see in a second. There are two types of charge controller - PWM and MPPT, and this is the better and therefore more expensive type. There’s a whole load of science behind how these work, but essentially an MPPT or Maximum Power Point Tracking controller varies the electrical load on the panels to make sure they’re always at peak efficiency.
Once upon a time it was deemed acceptable to connect the solar panels directly to the batteries - as long as you had a blocking diode to stop the batteries backfeeding into the panels at night - but in a modern setup you really should have a proper charge controller to manage everything as it’s more efficient and also safer.
This controller has a serial port for data logging - which I haven’t done anything with yet - and an app which shows realtime power generation as well as some basic historical data, and we’ll have a look at those figures shortly.
The charge controller is connected to this bank of 20Ah LiFePO4 batteries, which is a modern lithium chemistry which is very compact, safe and efficient. There are 4 of them connected in parallel for a total of 80Ah, which is exactly 1kWh of capacity at their nominal voltage of 12.8V.
How does a kWh work? Well, basically, if you hook something up that draws 1kW of power, these batteries will be able to power it for an hour, as long as everything’s 100% efficient - which is pretty much a physical impossibility - and I have to mention that because of, y’know, YouTube commenters and whatnot.
Still, it’s close enough as a general rule of thumb. Oh, and these batteries do have a built in battery management system or BMS, which keeps the lithium cells in good condition by managing charge and discharge rates and keeping everything balanced and whatnot.
Generally you shouldn’t connect batteries with their own BMS in parallel, and in a more sophisticated setup the charge controller will communicate with the batteries, but according to the manuals everything I have here is kosher and configured correctly - I have double and triple checked because I really don’t want to burn my house down.
But how do I know how much power is in these? Well, in the early days I basically had to estimate based on the voltage, but that’s not very reliable. So I hooked up this Renogy battery meter which uses something called a shunt, which goes inline with the input and output and accurately measures how much current is flowing either into or out of the batteries using a coulomb meter.
What’s a coulomb? Well, apparently it’s the standard unit of electric charge, defined as the amount of electricity that a 1A current carries in 1 second. But that’s not really important - all we need to know is that if we calibrate it when the batteries are empty, let them charge up and then calibrate it again when they’re fully charged, it’ll know how many coulombs it takes to fill them up. So all the meter needs to do is to measure the power going in and/or out in realtime and it’ll be able to give us an accurate level of charge at any given moment - in the same way that you can calculate your bank balance by comparing deposits with withdrawals.
Clever stuff!
The next link in the chain is this inverter. An inverter takes the 12.8V DC from the batteries and turns it into 220V AC, which is close to enough to what usually comes out of the wall here in the UK. It came as part of the Eco-Worthy kit that I bought way back in August, and to be honest it’s not brilliant but it does get the job done. It’s wired in parallel with the batteries and charge controller - obviously via a fuse - which is how the manual said to do it.
Charge controllers do have a load output on them but on a controller of this size it’s only designed for smaller loads like LED lighting etc. and it’s advised to connect the inverter up directly to the batteries like this.
Allegedly this inverter will deliver up to 600W continuous with peaks of 1200W, but this is another part of the puzzle that I may either replace or eliminate completely.
..and this piece of kit here is the reason for that. This is my EcoFlow RIVER 2 PRO which was very kindly sent to me for a review video which I did a while back. Much like the smaller EcoFlow RIVER 2 before it - which was also sent to me for review last summer - this has become a permanent part of the setup.
In fact, if I didn’t already have the bank of batteries here I could hook the solar panels directly into this using the XT60 connector on the back - it has its own internal 60Ah LiFEPO4 battery and it even has an integrated MPPT charge controller that’s good for up to 220W of solar charging, and a very good app that allows me to monitor power in and out, current state of charge and all of that stuff so it really could replace most of this.
Obviously when I was building this system I had no idea that EcoFlow would offer to send me one of these for free. So, what I’m using it for is a lot of extra capacity and a bit of insurance. It’s plugged into the cheap Chinese inverter and set to charge at its minimum rate of 100W. Although most of the time it just sits here fully charged passing that through, and of course I use the USB ports to charge my camera batteries and the power bank that I in turn use to charge my phone overnight.
If my other battery bank gets too low I can just switch the inverter off and run down the battery in this without any interruption in the flow of power, and then if I’ve still not had enough sun, there is a socket down here that I can plug it into as a last resort.
So, what about eliminating that inverter? Well, the thought has crossed my mind that I could just hook the EcoFlow up to the batteries directly using the 12V input on the back. It has its own internal full sine wave inverter after all and it’s much better quality than my original one.
But mixing and matching batteries on one charge controller is a big no-no, especially if they have their own BMS, so I’m not sure if it’ll affect the output from the Renogy or maybe even damage something. It would be fine in the evenings when the Renogy is basically doing nothing but the concern is whether it would try to charge this along with the other batteries.
Obviously the other inverter is kind of electrically isolating the two at the minute, so maybe I need some kind of DC to DC converter - or maybe I’m just overthinking things. I did buy the cable to connect it up, and maybe I could just use it at night, but for now until I get a definitive answer either way I’ll stick with what I know.
Anyway, how do I use this to power all these old computers and stuff?
Well, there’s a long extension cable which runs under this racking to my desk, and I have a big 8-way switched outlet which in turn goes to my laser printer, shelf lighting, overhead LED lighting that I use for filming and whatnot, my PinePower USB power supply, and up to my hifi amp and CRT here.
I also have a NAS that lives behind the desk which was only supposed to be there temporarily while I set it up over Christmas but seems to have made its home here.
I thought that these old computers would need hundreds of watts and that running them on such a small solar setup just might not be feasible, and that’s part of the reason I embarked on this experiment in the first place - yes, raw data is all well and good, but no matter how many videos I watched I struggled to take someone else’s data and use that to work out whether this will work for me in my situation and so I just decided to jump in and do it.
I can honestly say that every single video that I’ve made since this all went in has been powered by this setup - the batteries in the camera, the lighting, the laptop that I use to edit everything, the NAS that I use to back up my videos, my soldering iron, and indeed, everything you’ve seen on the desk here in that time - from computers to consoles and even a 1960s record player.
I’m also self employed and work from home at least a couple of days a week and it powers my laptop and everything I need for that too.
When I’m in here and doing stuff and the sun’s out the batteries are generally charging - if they’re not already full - and when it isn’t I can run what I need for about 2 days continuously on the batteries that I have here.
Even in the depths of winter - alright, not when the panels were completely covered in snow but they were generating again once it started sliding off. I could get away with a full day and evening without having to keep my eye on the battery meter and that’s all I wanted out of this setup.
So this was never really intended as an exercise in saving the planet or even saving money. That’s why I’ve spent so much time up to this point explaining the technical side of how it all actually works because that’s what interests me. Generating your own electricity is just really cool. I’m not even particularly interested in gathering data - although I will show you the basic stats that I have from my Renogy charge controller up to this point.
You can see that I’ve actually generated more power over the winter than I did at the tail end of the summer. The reason for that is that I’ve been finding more ways to actually use it - if the batteries are full and there’s no load on the system, then there’s nowhere for that power to go and so the system doesn’t generate anything. I’m not home all day every day and when I’m not here the inverter is off so I’m not fully draining it every day after all.
If my maths is right, then based on average electricity prices here in the UK, I’ve generated and used about £15 worth of electricity in the past 6 months.
Don’t get me wrong, we’ve probably actually saved a lot more than that because nowadays I turn everything off when I’m not in here. When it was all running from the mains I’d just leave stuff on all the time. But again, that goes back to what I said before about data and the effort of putting all of that together far outweighs the benefit of me sticking a graph up on screen that isn’t really relevant.
So, the truth of the matter is that I honestly think that a small DIY system like this can never really pay for itself in purely financial terms. Well - I mean it’s paid for itself multiple times over in my case thanks to YouTube ad revenue but I got lucky.
If you’re building something off grid or you want to use it for a camper or a boat then I think it’s well worth the expense. If you just enjoy tinkering with technical stuff and think that making electricity is cool then I’m right with you, there are far sillier things that we all waste our money on after all.
But a full rooftop solar system is going to be a far better investment in pretty much all other cases, because the price per watt generated is going to be much lower the bigger the system, and because it ties into the house electrics and you can actually use every drop of power that you generate. Or should that be coulomb? Anyway, we’re looking at moving house in the next year or so and it’s definitely something I’ll be looking into doing when we do.
Unfortunately, although this DIY kit is all pretty standardised and you can mix and match parts from different manufacturers, building what I have here into something that could power the whole house would end up being much more expensive than just getting a professional installer in to do it all from scratch. I’m hoping I’ll get a chance to reuse this in our next house in an off grid studio or garden office so it doesn’t go to waste. Just something to bear in mind.
So, that’s pretty much the long and short of it. I think that’s covered all of the various questions that I’ve had about this setup, thanks as always to my patrons, channel members and Ko-Fii supporters whose names you see on screen as I speak, thank you very much for watching, and my normal retro computing and gaming shenanigans shall resume shortly.
Original Video Links
My Solar Setup (Affiliate Links):
MC4 to XT60 Cable: https://geni.us/cnfLZg4
Renogy Rover 40A MPPT Charge Controller (Amazon): https://geni.us/z8ySS
Eco-Worthy 120W Solar Panel (Amazon): https://geni.us/2CId1Ax
Eco-Worthy 240W Off Grid Solar Kit (Amazon): https://geni.us/qwcc
Renogy Shunt Battery Meter (Amazon): https://geni.us/ohciTa
“Maxico” Kill-A-Watt Energy Monitor (Amazon): https://geni.us/wDAJ
Eco-worthy DIY Solar Kit (UK): https://bit.ly/3UnVniK
Eco-worthy DIY Solar Kit (US): https://bit.ly/3DWDBxK
EcoFlow RIVER 2: https://geni.us/vAA3G
EcoFlow RIVER 2 PRO: https://geni.us/2EbYZV
Further Viewing:
Solar Playlist: https://bit.ly/reessolar
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