Last week the installation of my two solar panels on the roof of the motorhome was completed. The work was done over two weekends by a local company in Essex called AK Leisure. The setup includes:
- 2 x 100 watt roof-mounted solar panels
- 1000 watt pure sine wave inverter
- A second 130 Ah leisure battery
- Two plug sockets wired into the inverter
- A wall mounted display panel
- Control panel under the bed box
I’m not going to go into all the technical details of it as I don’t fully understand it all but basically I have as much power as I can fit on my roof, and I bought a second battery which works on a separate system to the existing one.
Two separate leisure batteries
The first leisure battery is what came with the motorhome. I have no idea ho old it is or how well it’s been treated. I know that the previous owner had the vehicle for almost a year and never used it – it just sat on his driveway. Sitting idle for long periods like that is no good for the battery.
As the vehicle has had 11 owners in it’s 19 years, I dread to think what condition the battery is in! Having said that, I had it tested a few weeks ago when getting some other work done and was told it was fine, so I decided to keep it.
This one powers the internal electrics – all the lights, the water heater, the ignition for the gas cooker in the kitchen, and it also operates the fan heater on the gas fire (though this can also be run on gas.)
This is now known on the system as “Battery 2” and will be used the least. I will only use it for lighting.
The second battery that I bought is a good quality 130 Ah (amp hours) AGM battery and this one is connected to the inverter. The inverter is what takes the power out of the battery and converts it into the voltage required by the plug sockets.
I now have two dedicated pug sockets wired into it. One is in the kitchen and the second is under the desk where I have my computer. In addition, I have two other plug sockets that continue to work off electric hookup if I am plugged into mains / shore power. (EHU)
This battery is known as “Battery 1” and it is going to get hammered because it will be used by my computer equipment for several hours a day. The control panel allows me to set how much power goes to each battery. I have it 90:10 in favour of battery 1.
Note that battery 2 (the one that was built into the motorhome) will also get charged when I’m driving, and anytime I am on EHU. Battery 1 is ONLY powered by the solar panels.
Sunshine is the key
I said recently how I was in need of sunshine and that’s not just for my well-being, but also for the optimum solar efficiency. If there is no cloud cover, and I’m parked in direct sunlight they will work at maximum efficiency.
But of course, the weather makes a drastic difference. First of all, you have the number of daylight hours to consider. As we move into the summer months, the days get longer and that means more hours of potential sunlight.
But perhaps the biggest factor is quite simply cloud cover. When the sky is completely overcast as it has been for the best part of this week, hardly any power comes through because the sun is simply blocked by the cloud!
I made this image earlier in the week showing the difference in weather between where I am parked here in the UK, and what it is like in the area of France I will visit first. The nicer weather will not only put me in a better mood but will also provide me with more power 🙂
Now the testing begins
When I first got the system, I didn’t really understand all the numbers that I was seeing on the display panel but I knew the batteries were full so I just decided to test it out.
For around 8 hours I ran my small computer, and at times also my big one. I did some vacuuming, straightened my hair, and charged my phone. Over the course of the day the indicator bars dipped down and around 8pm I chickened out and shut everything off for fear of causing damage if I ran the batteries too low!
This was not a scientific test 🙂
Since then I have left the batteries to charge and have used only EHU. I have phoned AK Leisure numerous times to get additional clarification and I now think I understand how it works better. I was hoping I’d get some kind of display that would simply show a percentage in each battery but it’s not as simple as that.
However, today, they were charged fully; no more power was coming through. I now have a reading in AH for each battery so I can use that as a benchmark to tell me “okay when the battery is full it shows this number”.
So what I will do now is run a series of timed tests in the evenings. I will wait until the sun sets and no charge is going in as that would distort the numbers. I’ll run just one piece of equipment at a time off the inverter, and leave everything else on EHU. This allows me to test everything in isolation. I’ll run it for a few hours, time it and make note of the numbers.
I’ll do this over a series of evenings testing out my various different electrical items.
Also, during the day times I am going to start monitoring how much power comes into the batteries. I can test this by making sure nothing runs off the batteries during this time. I’ll log all the data along with details of the weather that day so I can build up a picture of how much power I can expect to receive on a given day depending on the weather.
I’ll publish another blog post in a week or two with my findings.
I have a video below showing the panels, the control box, Andy from AK Leisure explaining things to me, and my storage box after the work was done.