Photovoltaic solar energy is one of the most renowned renewable sources in recent years. A very interesting type of energy that offers a free and clean raw material, reasons that attract more and more citizens of the planet.
Thousands of businesses dedicated to the sale of solar kits have proliferated on the internet , kits at first glance very cheap but that hide a bad design that will make us lose a large amount of money. From AutoSolar we want to inform you about the four most relevant factors that many electronic businesses dedicated to photovoltaic solar energy offer fraudulently.
1. Parallel connection of batteries
On many occasions we have reiterated that connecting the battery bank in parallel is not a good decision . In fact, on our YouTube channel you can find a video about the dangers of parallel connection .
In addition, there is a constant circulation of energy between batteries, and some of them never reach 100% charge, so we accelerate their wear even more. Despite this, many websites offer solar kits designed with batteries connected in parallel. You can easily recognize them since they usually follow the following scheme :
– Solar inverter 48V +8 batteries at 12V: 4 batteries connected in series and the other group of 4 batteries connected in parallel.
– Solar inverter 24V + 4 batteries at 12V: 2 batteries connected in series and 2 batteries connected in parallel.
– 12V solar inverter + 4 12V batteries: the entire battery bank connected in parallel.
We advise you to always connect your batteries in series and if you need more autonomy, opt for larger batteries or rethink your solar installation to work at a higher voltage.
2. 24V solar panels that are not actually 24V
Solar panels at 24V voltage are made up of 72 cells and their maximum power point is established around 37V. Instead, many online stores offer 24V plates made up of 60 cells whose maximum power point is 30V. Be careful, if you are offered 60-cell solar panels with PWM-type solar regulators , since given the maximum power point of these panels, the regulators are not suitable. For this type of panels, you would need to use an MPPT solar controller which is more expensive and works more effectively.
3. Cheap batteries
Without a doubt, batteries are an essential part of a photovoltaic solar installation. Depending on your consumption needs, your solar installation will require one battery capacity or another . if they sell you a small battery, the total cost of the photovoltaic kit will be low but the useful life of said element will be reduced by more than half. The first two years you will not notice errors in its installation, but after this time it will begin to load very quickly and download much faster still.
It is essential that the battery you purchase has the necessary days of autonomy, high current charges and shallow discharges to maximize its performance as much as possible. Many batteries are undersized and are sold as a bargain, when really the only thing they will do to us is to have failures in our photovoltaic system.
4. High daily consumption: Wh/day
Not because it is the last is the least important, quite the opposite. We constantly see solar kits on the internet that are capable of covering very high consumption. We give several examples:
– On our website, you can see how in the description of each solar kit we offer an average of the energy captured by that system in both winter and summer. If we buy a solar kit, it is to use it throughout the year, so it is essential to know the energy that the system will offer us even in the months of less solar radiation. Unquestionably, during the summer months we have more solar radiation, which is why many electronic stores are only interested in showing this data.
– On the other hand, we must take into account our consumption needs. Are we going to consume throughout the day or at night? If the consumption is at night, we will need batteries with a large capacity and with the number of solar panels necessary to be able to produce the daily consumption of the home in solar hours. What do some ‘expert’ websites do in solar energy? They offer solar kits with a high number of plates and very small batteries. In other words, they sell cheap batteries with panels at very competitive prices, which results in a kit that we will have to replace in the short term.
In any case, if you want to receive a personalized quote, do not hesitate to contact us to solve all your doubts.