Solar Panels

Vertex Engineering, Trina, ZnShine and Tesla are some of the companies selling solar panels at varied prices in Pakistan.

The Need

With the drastic increase in global warming and carbon pollution, conservation of the environment has become the biggest challenge and concern. Also, the increasing cost of energy products has become inconvenient for the users. To protect our environment from further degradation and to save cost, greener forms of energy need to be adopted. 

Net Metering

The biggest advantage of solar energy in Pakistan is net metering. It is an advanced method of keeping a record of your electricity billing. Through this system, residential and commercial users who have solar systems for electricity generation are able to sell the extra electricity to the government. Net metering credits the owners of the solar system with the extra electricity that they contribute to the grid. 

During the daytime, the solar electricity produced is way more than it is needed. This extra energy gets added to the grid and will make the net meter run backwards. With the net meter, the bill sent to WAPDA will be in negative figures, meaning the WAPDA will owe you that amount. This will be adjusted against the energy that will be used by the setup at night or other times when the consumption is more. It is a known fact that electricity prices are extremely high in Pakistan and net metering is one of the few convenient solutions to our billing issues. 

Types

At present, four types of solar panels are available, monocrystalline, polycrystalline (also called multi-crystalline), thin-film and bifacial. All four types vary in their composition, cost, performance, appearance and the installations each are best suited for. 

Monocrystalline

The monocrystalline solar panels are the most efficient and perform the best amongst the three types. They are also very aesthetically pleasing but the downside is high costs. 

Polycrystalline

They cost lesser than the monocrystalline but are also lower in performance and efficiency.

Thin-film

These panels are aesthetically pleasing as well as being lightweight, flexible and portable but they are the lowest in performance and efficiency as compared to the other two types. 

Bifacial

Bifacial panels are also very popular these days. As the name suggests, they are capable of capturing sunlight from both sides of the panel hence producing double the power. Typically bifacial are manufactured with monocrystalline solar cells, but polycrystalline bifacial panels also exist. 

How Solar Panels Work

Solar systems harness solar energy by converting sunlight into electric current or heat energy. The conversion of solar energy into electricity is done through the solar photovoltaic (PV) effect. This electricity is used to light up our homes, offices etc. Solar Thermal Systems use another type of panels. They convert sunlight into heat energy that can be used for water heating or space heating. 

How Long Do They Last

Polycrystalline panels only last for 2 to 5 years. However, Monocrystalline typically last for 25 to 30 years. It is not that they stop producing electricity after that. It means that their energy production declines by a significant amount over the years.

Maintenance

These panels are constructed to withstand heavy beatings from rain, high winds and even squash ball-sized hail plummeting down on them. This means they cannot break easily and won't need any serious maintenance other than periodical cleaning. Being covered in dirt or debris will reduce their output by 5%. Usually, the next rain will take care of that but for climates where there isn't much likelihood of rain, the users will have to clean the panels to return them to their optimal efficiency.

The frequency of cleaning depends on the amount of pollution in your surroundings. Spring is considered a good time for annual cleaning of panels as the pollution is deemed to be less in this season as compared to others.

Cleaning the panels twice a year will bring a 5.1% increase in their electricity production as compared to the ones not cleaned at all. The cleaning process isn't complicated at all and owners can easily do it themselves by using a gentle soap, a soft brush to get the debris out of the corners and a garden hose to wash the dirt and soap away.

In any case, do not use harsh chemicals, abrasive materials as well as pressure washers, as they can seriously damage your solar system. 

Common Misconception

Most people in Pakistan have the misconception that solar systems are not capable of generating electricity at night because of the absence of the sun. The fact is, solar energy storage, grid connections and net metering allow your solar system to use electricity even during the night when solar production is dormant. This is done either through connection to the electric grid or to a battery, making solar panels a tenable round-the-clock energy solution. 

Potential Downside

Though solar energy is known for reducing carbon pollution, silicon emission from solar panels has been observed. This is because the silicon is the most commonly used material used as a semiconductor during the solar cell manufacturing process.