The process of adding solar panels to an existing system is not going to be the same as installing a solar system. There are a few factors to keep in mind.
Your rooftop must be able to have space to add new solar panels. If that is not the case then the answer is no. When compared to rooftop systems ground mount systems can be a bit easier to add onto as they are installed on land and it can be easy to add additional panels.
Figure 1: Installing new solar panels Space for new solar panels
Additional Energy need
If you are planning to add additional solar panels to an existing system, then it is important to know the energy need.
Depending on the no of additional solar panels added, you may need to change the size of the inverter too. When installing a new system, the solar technical will access the total energy needed and will size the central inverter for your solar array. This is based on the power output of the panels. The power rating of the inverter is generally smaller than the solar panels as the energy loss is taken into consideration when converter DC to AC power. Since adding new solar panels will change the size of the existing system, it may generate more electricity than the inverter can handle.
Adding a micro inverter is much easier as they are simply a miniaturized inverter that is suited for individual panels rather than a string of solar modules so there is no need to worry about the capacity issue of the panels.
Figure 2: A string inverter vs a micro-inverter (Released in 1993, Sunmaster 130S was the first microinverter)
Choosing the best solar panels - to find the right solar panels for your house, the below-mentioned points will help you to find out which type of solar panel will best suit your home.
For the guarantee period of the solar panels, the manufacturer must at least offer 25 years.
The cost of the solar panels is usually expressed in cost by W/c.
The manufacturer’s reputation. It will be a good idea to compare different solar panels offered by different manufacturers to have an understanding of what they offer.
The type of solar panel whether it is thin-film/monocrystalline/multi-crystalline.
The efficiency of the solar panels- this is an important point to remember as this will help you understand the sizing/installation of the panels. Panels range from 12% - 20 % and the prices increase with higher efficiency. So when the rooftop has a small surface area then choosing higher efficiency panels would be the right choice while with a larger rooftop surface one can buy solar panels with less power output at a more affordable price.
All PV modules have a temperature coefficient. So for every increase in panel temperature there will be a decrease in power output. This change is represented as0.3 – 0.5 %/degree Celsius. The lower the coefficient less power will be lost with an increase in temperature.
The by-pass diode box and the cables at the backside of each solar panel must be fixed properly.
The power tolerance of the solar panel is the amount of power that the solar pane can produce. For example, if a 300 W panel has a tolerance of -5/+5 % then it will produce between 295 – 305 W. The best power tolerance for a solar panel would be only positive power tolerance and no negative tolerance. For example 0/+5.
It is important to keep the mentioned factors in choosing solar panels. AE Solar’s new range of solar panels the Eclipse was launched recently. With their aesthetically pleasing design, these panels aim to maximize system power and system performance. The ultra-black series of Eclipse is the latest evolution in the solar industry in terms of design and efficiency.
Figure 3: The Eclipse Ultra Black Solar Panels
The Eclipse Ultra black solar panel series ranges from 305 W – 335 W. The panels deliver good performance and the warranty for the panels is covered for over 25 years. The panels are completely in black which gives a classy elegance and a sophisticated sense of style to the rooftops. The efficiency ranges from 18.20% – 20.8%. All the technical information is given in the data sheet below.
Figure 4: Technical Data Sheet for Eclipse Ultra black series
In Short, it is possible to add solar panels to the existing system regardless of whether you purchased it or rented it as long as there is still room left on your rooftop. You can always search for a new installer to add on more panels to your existing system but may have a harder time finding a company as most companies will avoid doing add-on projects for installations that aren’t their own.
When it comes to system size, companies will have a required minimum no of solar panels to be installed, and adding solar panels from a different company could also mean that you will be receiving different bills from different providers. This may also impact the tax rebate as in some places adding additional panels could mean that you will be forfeiting those tax credits/incentives. So, it is important to check and understand all these before installing additional solar panels.