Ampair distribute a range of solar power products, concentrating on the specialist needs of the marine and remote power market for high quality systems. We are the exclusive UK distributors of the Flexcell range of flexible solar panels, and we complement these by distributing the Sunware range of semi-rigid solar panels as well as a range of selected rigid solar panels so that we can offer a panel and accessories to suit any situation.
The term "solar panel" can mean either thermal solar panels used to heat hot water ("thermal solar") or solar photovoltaic panels used to generate electricity ("solar PV"). At Ampair we are only involved in solar PV and this is what we mean when we talk about solar panel.
From a client perspective the thing to understand about solar panels is that you cannot get something for nothing. If the panel is made more flexible, robust, and shade resistant then it tends to lose efficiency and become larger and more expensive. The same is true of the other elements of a solar power system such as regulators, DC to AC inverters, or batteries. And of course it is always possible to find lower quality stuff if you try hard enough – but you may not necessarily pay less.
Flexcell flexible solar panels are about three times the size of semi-rigid panels of the same power output. In price terms they are about the same for a given power output but because a semi rigid panel is backed by a stainless steel plate it can only bend a limited amount. In contrast a Flexcell panel is bonded onto a piece of fabric and so can be rolled up – but not folded. Whilst Flexcell flexible panels can be walked on they cannot be carelessly trampled on in quite the same way as one can with a Sunware semi-rigid panel.
A unique advantage of the Flexcell flexible panels which derives from the way the silicon is arranged is that the panel can be partially shaded without losing all the power output. Quite a lot of shade can be cast onto a Flexcell panel and only a proportionate power loss will be experienced. In contrast a solid bar of shade across a semi-rigid panel (or most rigid solar) will completely stop useful power production.
There are two types of Flexcell panel termed Sunpack and Sunslick primarily distinguishable by the tradeoff between durability and stowability. The least durable is the Sunpack which as a result can be tightly rolled around a dispenser which contains a standard car (auto) socket and therefore can be just unrolled and used to charge any equipment that is supplied with a car charger. The Sunpack dispenser also contains a car charger in such a way that multiple Sunpacks can be linked together. The Sunpack is ideally suited for mountaineers, lightweight campers and cyclists, or where a little emergency charging power is needed in a no hassle manner. The Sunslick panels are heavier duty and so cannot be rolled up as tightly. They are better suited to less controlled environments such as long duration expeditions, or onboard small boats and yachts. Depending on the size of the battery bank to which they are connected it may also be advisable to fit a compact charge control regulator to protect the battery from overcharging. The Sunslick panels are supplied complete with a very good waterproof plug and socket so that a wiring run can be left ready to use but the panel disconnected when it would be in the way. This makes them ideal for use by sailors who wish to lay them out on deck or drape them over spray hoods or boom covers, such as for charging a battery when a boat is on the mooring. All the Flexcell panels have eyelets so that they can be tied down with rope or bungee cords, or clipped into canvas fasteners.
At Ampair we have chosen to stock the Sunware range of semi rigid solar panels because these are the best quality semi-rigid panels available. Semi rigid panels are typically mounted on the decks, hatch covers, and coach roofs of yachts and similar marine locations such as buoys. They are extremely robust and will withstand being trampled on to a reasonable extent although one should be careful not to shear or split the blocking diode connection which is an encapsulated block where the cable joins the panel. They are normally screwed, glued* or clipped onto the mounting surface and the mounting surface can be curved in one plane. A particular feature of the Sunware panels compared with many alternative semi-rigid panels is that they have either 39 or 40 cells per panel, versus the 35 or 36 cells in many other panels. Those extra four or five cells are important when the temperature is high – for example in intense sunlight or in high ambient temperatures. The reason is that each cell in a panel produces a bit of voltage and all the cells working together create enough voltage to drive a current into a battery. It takes about 35 cells to drive a current into a battery in typical conditions, however if you heat a cell up a bit then the voltage reduces and if you heat them up enough it will take up to 39 cells. So the irony is that a lower quality panel will stop charging batteries in sunny conditions. A related feature of the Sunware panels is that they have a white background so as to reflect the sun and so minimise the heating effect, whilst many other panels are produced with a black background which undoubtedly looks prettier but makes the heating effect worse.
* A suitable adhesive is SikaFlex 292 which is available in 300ml tubes for standard skeleton guns (see http://www.sika.co.uk/ for more info).
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Racing yachts and ocean monitoring buoys both use tough but efficient SunWare semi rigid panels
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We have chosen not to tie ourselves to any one manufacturer of rigid framed solar panels and instead try to choose the best panel available in any given size at any given time. There are three or four rigid panel sizes which are suited to particular aspects of the marine market and because of our diverse range of contacts with manufacturers and our depth of experience we are often able to source specialist solutions.
Most of the rigid panels have relatively high efficiencies and so are the most compact way of producing power from the sun. Similarly most have a tempered glass front and so are relatively fragile – they certainly will not survive being walked on or having a vandal throw a brick at them. They are also relatively cheap compared with flexible or semi-rigid solar panels which is why they are the panel of choice for large scale housing solar projects. There are a few exceptions to the rules about rigid panels and we can help to a limited extent if you need a vandal resistant rigid panel.
To accompany the solar panels there are a variety of other bits which may be needed. In a very simple installation, such as a Sunpack in combination with a cellphone charger, or a small Sunslick straight on to a 100 amp hour battery then there is no need to buy anything else. If the amount of solar panels could overcharge the battery then one should fit a regulator and we supply a range of these. Similarly we supply batteries – almost always deep cycle absorbent glass mat (AGM) lead acid batteries. We also supply stand alone and grid tie inverters and choose between several different manufacturers to suit the needs of each client. All the inverters, and combi charger/inverters, that we supply are sine wave inverters rather than cheaper semi sine wave (also termed pseudo sine wave) inverters.
We tend to avoid most of the battery charge state indicators which are on the market as, in our opinion, they are at the point in their evolution where they are extremely complex, not reliable indicators, and very expensive. Clearly this situation will change as designs evolve but for now we tend to recommend very simple instrumentation consisting purely of voltmeters and ammeters on the supply and load side of the batteries. Good quality digital and analogue volt meters and ammeters can be sourced cheaply, are easy to install, simple to use, reliable, and if they do fail will not cause your system to be unusable.
