As a general guide, mono-crystalline and hybrid panels have the greatest efficiencies (up to 20.4%). The efficiency of the panel describes the percentage of energy captured per m². This means that 250W hybrid or mono panels tend to be smaller than those of polycrystalline or thin film technologies. Monocrystalline has been considered a better choice until recently when the new generation of polycrystalline panels have achieved equivalent outputs.
The cells are very dark (almost black) and can be visually preferable to polycrystalline panels. The dark cells cause the panel to heat up more than poly panels, leading to a small degree of efficiency drop.
Polycrystalline modules are recognisable by their blue opalescent appearance. These panels are traditionally slightly less efficient in most cases than monocrystalline so may take more space to achieve the same peak output. New generation poly panels are becoming popular as they have been proven in field tests to outperform mono in varied light levels and can provide the highest yearly returns in Northern Europe (Great Britain!). They have the additional advantage of being cheaper than the high end mono panels. With efficiency of poly being constantly improved and lower production costs polycrystalline is becoming increasingly popular.
Thin-Film or Amorphous Silicon panels require the most amount of space as they have the lowest peak efficiency. These panels are less susceptible to the effects of shading and efficiency-drop when the module gets hot. These modules are the cheapest per watt, but can show higher yields than either mono or poly crystalline panels in some situations. As they are available frameless they are more suitable for building-facade cladding and large commercial roofs. Modern CIGS (Copper-Indium-Gallium-Selenium) modules have extremely attractive appearance, efficiencies of up to 13.4% and excellent energy yields, with the potential for greater improvements in the manufacturing process many people predict that thin film will become more widely used in the future especially in industrial applications.
Hybrid Technologies, such as Sanyo/Panasonic’s HIT (Heterojunction with Intrinsic Thin layer) modules are made of a thin mono crystalline silicon wafer surrounded by ultra-thin amorphous silicon layer. These panels are among the most expensive but have very high efficiencies and generate more clean energy than other conventional solar cells, even at high temperatures and in a wide variety of conditions. Monitoring of our hybrid panel systems has proven that they perform exceptionally well year in year out.
Other differences in panels relate to the construction of the frames (aesthetics or which sides of the module can be clamped for mounting), the construction of the backing sheet (aesthetics and front or rear circuitry) and the number of bypass diodes (affecting performance in different shading).
Each difference will have an impact visually and on performance in different scenarios, our database of every MCS-approved product and our computer modelling software allow us to design the best possible system for any given location and present the information to you in a clear and concise way.
The most important thing to consider when choosing your equipment is the performance of the system and your yearly yield of both energy and revenue. Using our software we are able to design every system to achieve the highest performance possible while remaining cheaper than off-the-shelf kits. A well designed and properly installed system can achieve up to 25% improvement on the forecast yield from SAP calculations.
Do not hesitate to ask questions, our design and installation team enjoy finding the best solutions for any project.