Solar Panels come in different sizes, type, power, brand, tolerance, colour, material and warranty. The main thing to consider is that the panels you chose are Tier1, CE and MCS marked.
Firstly there are two main types of panel; Monocrystalline and Polycrystalline. They are currently the most commonly used and are manufactured in quite a similar process using crystalline cells made from silicon.
The raw material for silicon is sand, a most abundant element. However, the process to turn sand into premium quality energy conducting silicon is a complicated and expensive process which involves many processes;
• melting sand in specially shaped furnaces
• adding chemicals and elements, including Boron to positively charge the silicon
• aligning all atoms
This process results in the manufacture of cylindrical shaped silicon ingots.
Monocrystalline panels are made using paper thin wafers cut from a single ingot of silicon. Polycrystalline panels are made from cells made from melting several silicon crystals together. Monocrystalline cells are higher in efficiency and this is usually reflected in the price.
Metal conductors and an anti-reflective coating is added to each cell to allow the conversion of solar energy into electricity, before thinly diffusing phosphorus over each, which provides the negative charge.
The cells are linked and soldered together, and glued to a back sheet. After which a layer of glass is added on the front side and it is sealed around the edges with a frame to prevent water and dust affecting the panel. The size and power output of the panel will depend on the number of cells used. Typical sizes are 60 and 72 cell panels.
The colour of panels vary depending on whether they are Polycrystalline (blue) or Monocrystalline (black) and both reflect light differently. The colour of the backing behind the cells (white or black), and the colour of the frame (silver or black), can also change the look/appearance of panels.
A junction box is added to the back of each panel to enable the extraction of the generated energy from each.
All Tier 1 panels are tested against Standard Test Conditions (STC), electrical parameters are recorded and you will find performance details on the manufacturer’s data sheet. This will also include details of the warranties and manufacturing tolerance (allowable deviation against the stated power output).
The Solar People only supply and fit Tier 1 MCS approved panels.