Engineers have been tasked to improve solar panel efficiency since the last century. Our first photovoltaic panel only worked to an efficiency of about 6 percent. But this meager performance is the result of a major breakthrough in science as we brought out our first commercial photovoltaic device in human history.
After the successful use of solar panels on spacecrafts, interest and research on photovoltaic panels intensified. Plans were made and approvals were given — funds poured in. Improvements came in rapid bursts, bringing the efficiency of commercial solar panels to about 20 percent. In less than 60 years, we more than doubled photovoltaic efficiency.
Currently there are photovoltaic panels that boast 30 percent efficiency. These are specially doped triple junction cells that began its development as dual junction cells. However these phenomenons are largely confined within the laboratory and engineers are still unable to produce such solar panels in large quantities without charging consumers an arm and a leg for it. More work remains to be done before common retailers stock up solar panels endowed with this technology.
In practical there is nothing much we as consumers can do about technology. You may be surprised the little we do to make our solar panels achieve top efficiency really goes a long way — this is because solar panels are designed to last for decades, and small differences add up.
Installing our photovoltaic panels in the right orientation and tilt angle is the most important thing we can do. The optimal position helps photovoltaic panels receive the most sunshine throughout the day and across different seasons of the year. This helps reduce the payback period. If your panels are sited in the northern hemisphere, then you will have to orientate your solar panels southward. You also need to tilt them to the correct angle, depending on the latitude of your photovoltaic panel site. The correct installation position will allow your solar panels to be exposed to direct, unobstructed sunshine from 9am to 3pm everyday.
Most homeowners do not understand the adverse effect that shading can have on their solar panels. Even if only one solar cell is shaded, its entire solar generator’s power output can be dramatically reduced. The individual photovoltaic cell that is now shaded acts as a resister that drains the electricity generated by its neighbors. As resistance increases, power reduces.
Another seemingly minor event that reduces solar panel efficiency is the accumulation of dust on the glass surface. This dissipates sunlight that would otherwise reach photovoltaic cells for power generation. Because dust and dirt will collect after a while, we have to wash the glass surface regularly. If you’re living in a relatively dust-free environment, this should be an infrequent activity.
Temperature also affects photovoltaic panel efficiency. The higher the temperature, the further its efficiency drops. Unfortunately more heat is collected as solar panels experience more sunshine. Thus efficiency tends to taper as sunlight intensity increases. Therefore we have to ensure that our photovoltaic panels are installed sufficiently far away from roof shingles. The gap in between the roof and solar panels also allow air movement to bring away additional heat that may otherwise be trapped there.