Here are RenewSolar one of the primary goals was to fix things that others have done wrong and make solar work for you. One of our clients had noticed there was some issues with there installation of solar ( we installed the batteries and inverter). But the MCS installation was causing issues.
The Key problems we think is happening:
Getting qualified these days is easy, its costly but passing exams has never been so easy, and while that bit of paper means a lot to most, over our decades of running businesses we have never found a qualified person that can do the job.
Solar may seem mystic to many but the principles are rather simple, a basic understanding is what most people have, in that solar panels are DC and the inverter changes this to AC. We then use AC in our homes. There is then some “technical” specs such as how much power, voltage and current limits as well as wiring standard (BS7671)
The problem you have is that DC works differently to AC power and AC systems are different and the application of AC principles do not always apply to DC. This opens a host of messed up installations, but the cash cow at the moment is solar, so you have a lot of band wagons.
With the inflated prices of solar and installation, you can see why there are many who want to make a quick buck, usually around £2-£5,000 for two days work. Shocking right?
The Problems.
The inverter installed here is a Deye/Sunsynk 8kw inverter, it has 2 mppt’s and four connections so you can combine solar strings.
As you can see there are three isolators meaning that there are three solar panel arrays wired into the inverter, the problem here was not that they were all different, but the problem here was voltage and diode related.
The problem from the west.
The installer did not seem to read the manual or understand the specs wrote on the side of the inverter, therefore had ran the solar arrays at a low voltage, however to combat this they ran two arrays on the same plain in Parallel.
Normally this is not a big problem, its not the most effective way as higher voltage wins when it comes to solar, but the strings were not equal.
Therefore you had mixed voltage arrays in parallel, which of course means the higher voltage is pushing back on the lower voltage array.
Not only does this lower output, but there is a diode loss, a voltage loss and a current loss from all of the array.
The response from the MCS was “the app told me to do it”. I’m not sure the app told him to not read the manual, not follow manufacture instructions and don’t follow BS7671 as well , but common sense in DC systems and any technical knowledge of solar system has been disregarded in this installation.
Such a simple error fixed.
What we did was fix the poor wiring, and then change the two strings to one, They were no longer in parallel and we tested the string voltages and currents to ensure that they were “in spec” once we had done this and of course of general knowledge and ability to read, we fitted up the system and within hours the client reported the “best he has seen”.
Wider Problem Solar.
Solar installers are not really solar installers, they are “lego men” this is really similar to mechanics and fitters. A mech will look and hear the issues, a fitter changes parts until they luck out and blames his lack of skill on a computer. Lego men put things together, and don’t really know how they work and why they work.
But you have to ask your self…. if you have had solar installed, is it the best it could have been?
Could there be some dangers, errors and you just haven’t noticed?
Known problems:
For the past few years installers have been putting in batteries into homes as a “token” however they may claim 10 years or 5 year warranty and the battery will fail. The reason the battery will fail, is because they are not fit for purpose and this falls under workmanship warranties. You could claim from your installer if and when the battery fails if the work warranty is longer than the battery warranty.
While they will claim its a battery issue it more than likely will not be.
If you read the 5 or so posts on battery management that we have made, you will see that there is a long line of variables which effects the battery performance and life. You are likely to see problems in 5.47 years from the installation date in the longer term the failures could be seen in around the 8.21 years.
Why? Poor installation and technical knowledge. here are some key factors…
Loft installations will see degradation of up to 2.8% per year just because of the heat.
DOD ( state of charge range) running a battery low will reduce its life cycles dramatically.
Trash battery – some batteries were trash and lose 30% of there cycle life out of the box.
Loading – Batteries with a too higher charge and discharge current will lower the life cycles.
There are free articles on our website and you can buy our 15 page report from the shop which will give you some details on the real world of battery performance and life. The report was generally related to our 50kwh battery performance modeling, but shows were problems can exist.
Cant these problems be fixed?
Yes, as a short answer, but we don’t believe in throwing good money after bad.
For solar installations there is a solar inspection which will review your installation. This report can be used in evidence. We can review the system and make the necessary upgrades ( if needed) and you benefit from our low prices. The chance that you come to find this information, means that your probably have a significant issue already.
You can replace the battery, add to the battery if this is the issue. you can have your solar re calibrated. you can have a battery and inverter replaced or what every it takes to fix the problems and makes solar work for you.
We will give you options, so its kinder to you.
If you were scammed with rent a roof and FIT, we have a separate information page. Upgrading from FIT
Fit and battery storage.
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