personally I would never buy from a seller that spouts such tosh!

NO panel is 100% efficient. the best on the market at the moment are about 18% efficient and cost double the price of this panel.
This panel is a domestic panel, it is not designed for vehicular use. Now, you can use domestic panels, that in itself isn't a problem. I supplied one for my uncle to use on his yacht, but I made sure it was one man enough for the job, and a yacht is a very different environment to a truck.
It isn't 24V. Not that this matters especially, the regulator can deal with that, but it's still more tosh.
I have never heard of this panel. that may or may not be a problem as there are so many you can't know them all, but I am instantly suspiscious of panels with names I don't recognise, because there is a lot of tosh out there.

Now of course, it's entirely possible I don't know what I am talking about, but my company is Dorset Solar Power Ltd

Thanks for your thoughts Moggy! Will have a look for another, did seem very cheap for the wattage when compared to others.

More reading - where efficiency counts is in a race ...

AERL - Solar Charge Controller - MPPT solar car controller

Thanks for all the information guys.

Just one question: Is there actually such a thing as a 24V panel? Alot of them say 12v/24v?

I take that to mean that it's basically a 12v panel that can be used via an MPPT controller to charge 2x12v batteries wired in series (ie a 24v system).

If so, I can buy any panel described as 12v, and use it with an MPPT controller to charge my 24v system? Or am I missing a trick?

Cells within a panel can be connected together to form close to a desired voltage. Panels can also be connected together to form larger voltages (series connection) or connected together to form larger currents (parallel connection) at the same voltage ...

MPPT can be designed to BUCK (reduce) the voltage OR to BOOST (increase) the voltage.

The variations are large. What works best depends on the installation;
all panels lit to the same degree all the time?
load is best at what voltage?
money?

And of course what is available

Hi Warin,

THanks for your thoughts.

Basically want to make sure our fridge can keep working, as it has an internal regulator that cuts the fridge off when it senses the batteries are down to 22.8volts.

Load of the fridge is 4.5 amps per hour, but presume this is if running continuously.

I have some LED lights too but the draw these make is very small.

So all up a panel capabale of 5 amps per hour charge.

I really don't want to have 2 panels wired together. Ideally want one panel that can charge the 2x12v batteries wired in series.

David