Solar Panels

Solar panels use Photovoltaic cells to make electricity from light. Photovoltaic systems use daylight to power ordinary electrical equipment, for example, household appliances, computers and lighting. The photovoltaic (PV) process converts free solar energy - the most abundant energy source on the planet - directly into electricity. Note that this is not the familiar solar thermal technology used for heating and hot water The PV array consists of a number of individual photovoltaic modules connected together to give the required power with a suitable current and voltage output. Typical modules have a rated power output of around 75 - 120 Watts peak (Wp) each. A typical domestic system of 1.5 - 2 kWp may therefore comprise some 12 - 24 modules covering an area of between 12 - 40 m2, depending on the technology used and the orientation of the array with respect to the sun.

PV panel prices

Most PV modules deliver direct current (DC) electricity at 12 volts (V), whereas most common household appliances run off alternating current (AC) at 230 V. An inverter is used to convert the low voltage DC to higher voltage AC. Numerous types of inverter are available, but not all are suitable for use when feeding power back into the mains supply. Currently we are able to offer our latest range of Pulse Width Modulators (PWM) controllers that perform both the inverter function and control the PV panel.

Pulse Width Modulator (PWM) charge controller

The Microcontroller based PWM charger is an efficient and advanced charger suitable for solar power utilities. It adopts latest PWM technology. It reduces power loss and efficient charging of battery and thus reduces the overall system cost to the tune 30%.

Other components in a typical grid-connected PV system are the array mounting structure and the various cables and switches needed to ensure that the PV generator can be isolated both from the building and from the mains. Again,good suppliers and installers of grid-connect PV systems will be able to offer advice on these aspects of the PV system. Finally, a meter
will be required to ensure that the system owner can be credited for any PV power fed into the mains supply.

Types of PV panels

Monocrystalline Silicon Cells:
made using cells saw-cut from a single cylindrical crystal of silicon; this is the most efficient of the photovoltaic (PV) technologies. The principle advantage of monocrystalline cells are their high efficiencies, typically around 15%, although the manufacturing process required to produce monocrystalline silicon is complicated, resulting in slightly higher costs than other technologies.


Multicrystalline Silicon Cells:
Made from cells cut from an ingot of melted and recrystallised silicon. In the manufacturing process, molten silicon is cast into ingots of polycrystalline silicon; these ingots are then saw-cut into very thin wafers and assembled into complete cells. Multicrystalline cells are cheaper to produce than monocrystalline ones, due to the simpler manufacturing process. However, they tend to be slightly less efficient, with average efficiencies of around 12%., creating a granular texture


Thick-film Silicon:
Another multicrystalline technology where the silicon is deposited in a continuous process onto a base material giving a fine grained, sparkling appearance. Like all crystalline PV, this is encapsulated in a transparent insulating polymer with a tempered glass cover and usually bound into a strong aluminum frame.


Amorphous Silicon:
Amorphous silicon cells are composed of silicon atoms in a thin homogenous layer rather than a crystal structure. Amorphous silicon absorbs light more effectively than crystalline silicon, so the cells can be thinner. For this reason, amorphous silicon is also known as a "thin film" PV technology. Amorphous silicon can be deposited on a wide range of substrates, both rigid and flexible, which makes it ideal for curved surfaces and "fold-away" modules. Amorphous cells are, however, less efficient than crystalline based cells, with typical efficiencies of around 6%, but they are easier and therefore cheaper to produce. Their low cost makes them ideally suited for many applications where high efficiency is not required and low cost is important.