for your setup you could achieve the same with a few smaller MPPT units, to prevent possible shading.
On my boat in the US I have 3 panels with 3 small (75/15) Victron MPPT's feeding into my battery bank
On my barge in Holland I have 4 panels with just 1 MPPT
The cost for the 3 MPPT's was about the same as one larger one of the same capacity. The advantage if one would go bad, there would be still 2 working, the disadvantage...more cables.
There is another way.
2 years ago I had solar panels installed on the roof of my Sydney home.
As our roof suffered from serious shading from a neighbour's property the installer introduced me to the Enphase Microinverter system. He explained under this system, in which each individual panel is fitted with its own "Microinverter" the output from each panel became 240VAC. Each panel works in phase with the Grid power, so all panels feed to a single supply to the house switchboard. The outcome is that:
1. Output from any panel shaded at any particular time will of course be reduced but, unlike the traditional MPPT system, this does not influence the output of the other panels.
2. Panels can be individually sized and of different brands or types. The original installation may include a variety of panels to cater for roof geometry, or other panels can be added later without consideration of the type or brand of the existing panels - all output is 240VAC and in phase, so all can feed together.
Last year we undertook to fit to our Tjalk Anna Maria the 6 Q-Cell 265W solar panels we had bought for the purpose the previous Autumn.
The Enphase system was an obvious choice (jettisoning the MPPT device we had bought at the same time).
For our cruising barge, every mooring brings it's own shading problems!
The unknown was how to integrate this system to our Victron Quattro power management system rather than the Mains Grid . After discussions with Matthijs Vader of Victron I felt confident I could essentially treat the solar output as "Shore Power" and feed it into the Victron on that basis.
My problem was how the make sure the Victron took the role of setting the phasing of the AC input from the panels. I had much frustration in attempting this.
Eventually, on our return to our most common winter berth (Workumer Jachthaven, Workum, Friesland) the problem was solved by Wytze Veenstra, a local Victron specialist in nearby Sneek - my Victron Quattro, installed in 2008/9 needed a software tweek to manage the "phase matching" (2010 or later Quattros are already capable).
We have been every bit as pleased with the result (land based in Sydney and waterbourne in NW Europe) and would highly recommend both the Enphase system and Wytze Veenstra,s expertise.
De Vrouwe Anna Maria
The following user(s) said Thank You: Simon Sparrow, Paul Strawbridge, Steve Van de Pas
Paul Strawbridge wrote: As I mentioned, Steve, we have 6 new panels and are in deepest-darkest north Netherlands and we are getting 12KWhrs on a sunny day, so you should do better.. Today has been very overcast pretty-much all day and we have generated 6KWhrs. Hence I ask whether you might be better updating with maybe 6 new panels and more efficient rather than adding 4 more older units (?) Anyway, might be worth considering.
As I mentioned, Steve, we have 6 new panels and are in deepest-darkest north Netherlands and we are getting 12KWhrs on a sunny day, so you should do better.. Today has been very overcast pretty-much all day and we have generated 6KWhrs. Hence I ask whether you might be better updating with maybe 6 new panels and more efficient rather than adding 4 more older units (?) Anyway, might be worth considering.
We go > Mediterran , and lying mutch in the wild. we do indeed consume quite a bit, we cook on induction, but we have to do this on shore power or generator, rather than gas on board!
on a sunny day I get a 5-6kw my constant consumption is a 270w-400w day / night .
At night he has used so 20% of my batteries 600amp 24V and he has trouble getting it back full by evening
So I'm a little tight, so I would have liked a little more ‘jus”
I have learned and documented a lot thanks to all of you. but probably everything will have to happen this winter in the south, because here in Burgundy there is not much choice and the are not so customer-friendly, only the word "boat" scares them off.
Question; who knows a good and familiar company in solar panels / installation region Canal de Sete> Beziers/ Capestang ??
How much power do you need, Steve? We have 6x300W panels, are in Friesland and in May regularly got >6KWhrs and this month >8. Today, very overcast much of the day, 7KWhrs. We use about 5-6KWhrs a day so not sure what we could achieve as quite a lot goes to waste. We have an electric hob & oven but only one fridge/freezer. I wondering if just upgrading what you have might achieve your goal, in other words replacing with new kit (as opposed to being limited to match you existing) might be a longer-term option.
Andrew is correct, but various more things to consider. The new panels need to be very similar in specification to your existing system. Most importantly they must be the Polycrstalline type, be 240 w and be very similar voltage 30v and ampage 8A.
More importantly , from the photos you have a Vario Track MPPT charger rated at 80Amps, which appears to be a VT-80 which can take a maximum of 2500W or 10 x 240W panels, but be aware that it is also limited to 80Amps so with 10 panels you will be right at its limit with no safety margin (some countries require a maximum of 80%)
You will need to find out how the panels are connected 2 strings of three or three of two. This may sound complicated but by following the cables from the Vario Track to all the panels a simple sketch can be put together. This will have an impact on whether 3 or 4 extra panels can be installed.
I have attached files of the specifications of the Vario Track and panels.
The simple answer is yes its possible. But how you go about it is different dependent on the current system setup and limitations.
For example type of solar controller/controllers fitted. Array configuration parallel or series or as I suspect with the panel voltage on your label series parallel combined. If the system is old and uses an older type controller (PWM) then a more modern controller (MPPT) may give more output to the batteries without installing additional panels. Do your panels tilt to gain best angle to the sun
I had a quick google and there are solar panels out there at 240W which have almost identical characteristics.
What is your daily power consumption as 6 x 240W is already quite a large array. Do your panels suffer from shading/shadowing?
The following user(s) said Thank You: Steve Van de Pas
You know, electricity is not my thing... and it is like Chinese for me.
I search the forum, but find not an suitable answer for me
We have a great need for more electricity now, there are 6 panels of PMAX 240 , type panel NSI240/60-P on our roof, proves to be insufficient. there is still room for 4 extra panels, but I fear that the current panels are no longer available (see atachemet)
my questions, can I add additional panels that have a different brand and (probably) not the same values? So yes, witch ones?
does anyone know a trusted address in the vicinity of Dijon (for now) or in the south (canal de sete-canal du midi), later in the summer?
We have a Struder as an inverter and he can take Shure more extra power