A critical component of solar panel performance that often goes unnoticed is the bypass diode. In this blog, we will explore why the number of bypass diodes is important in a solar panel and how they impact its overall efficiency and reliability.
Understanding Solar Panels
Before explaining the significance of bypass diodes, let’s briefly understand how solar panels work. Solar panels consist of photovoltaic cells that convert sunlight into electricity. When exposed to sunlight, these cells generate a direct current. But when solar panels are shaded (by buildings, trees or cloud cover) or obstructed (snow/ice, bird droppings, dirt, etc), there can be a decrease in performance.
The Role of Bypass Diodes
This is where bypass diodes come in. They are like traffic police in a solar panel system – when one route is blocked, the traffic police will set up diversions. In a solar system, this is what a bypass diode does. The bypass diode’s primary function is to ensure the smooth flow of electrical current by bypassing shaded or obstructed cells, allowing the unshaded cells to continue generating power. These diodes are typically placed in parallel with groups of cells within the solar panel. When a cell or group of cells is partially shaded, the corresponding bypass diode activates, creating an alternative path for the current to follow.
By having multiple bypass diodes, if a part of the solar panel is shaded or obstructed, the diode corresponding to that section activates, allowing the unshaded sections to continue generating electricity at maximum capacity. This helps optimise energy production and ensures that the shaded area does not significantly affect the overall performance of the solar panel.
The Genie Insights Design
Most conventional panels only have three bypass diodes – if one cell is shaded, total power reduces by one-third). In contrast, the Genie Insights high-efficiency 50-watt panel (powered by MiPV technology), commonly employed in ‘trickle charge systems’ like those used to maintain transport refrigeration units and electric vehicles, boasts 44 cells with 22 bypass diodes. This configuration ensures that in the event of a pair of cells being shaded, the current can seamlessly reroute to adjacent cells, resulting in minimal performance loss solely from the shaded cells.
Bypass diodes may be small components within a solar panel system, but their impact is far from negligible. They play a crucial role in ensuring that solar panels operate efficiently, reliably, and with a long lifespan. The number of bypass diodes matters because it directly influences the panel’s ability to handle shading and varying light conditions, ultimately affecting the overall energy production.