Best Tips on Choosing Solar Panel Wattage

Solar panels, also known as solar batteries, photovoltaic cells, solar cells, or solar collectors, are popular things nowadays. Sometimes, even common users show a technical understanding of the solar battery nuances, particularly in terms of their mounting and use.

Currently, more than 1,500 solar battery manufacturers worldwide are working to satisfy the growing demand. An overview of popular 300 watt solar panels will be provided here.

Solar Panel Wattage Requirements

How to determine solar panel wattage required to power all the appliances you need to connect? The number of solar panels depends on how much energy may be needed on a daily basis. The capacity of a battery bank depends on how many days a power supply system has to last without additional solar energy. The charge controller, which helps to manage energy between solar panels and battery banks and keep batteries from overcharging, must be properly chosen as well. The size of the inverter used as well as the general-purpose wires you need depend on the appliances you want to run within the system. Make sure you know the exact number of appliances you wish to connect as well as the power consumption rating or output rating of each device. It can be listed in watts, volts, amps, or milliamps. Should you have problems looking, just google a similar device and put down its output rating.  You can also look through your electric bill. Make sure you decide for yourself how many days you may need to use each appliance and put the numbers down. Use a special online off-grid solar calculator to define the size of your solar system based on the general number of hours and output rating of all essential devices. These calculators help to decide on the size of the battery bank, solar panel wattage, and solar charge controller needed for the correct functioning of the installed system.

Should you decide to place a solar collector power system on the roof of a house or land, you might be confronted with a difficult choice of appropriate equipment selection. The key element is a solar collector. Solar collectors last for about 25-30 years, and high-tech principles used during their manufacturing are improved almost every year. That is why it is quite difficult to have a ranking score or scorecard with calculated performance for a particular product, which should help with the selection of an appropriate solar collector.

To choose the best solar cells, it is worth paying attention to these 5 criteria: 

  •  Cost 
  •  Brand name 
  •  Warranty and degradation rate 
  •  Performance ratio 
  •  Temperature specifications 

Types of Solar Panels

It is important to distinguish between monocrystalline and polycrystalline solar cells. 

Lower-efficiency polycrystalline solar cells, or “multi-crystalline” solar cells, provide higher performance on wide territories.

Higher-efficiency monocrystalline solar cells show their advantages within a limited area.

Actual technical characteristics of solar panels are presented within the PVEL (independent laboratory for solar industry products) rating and DNV (international certified gradation society). Both of them conduct tough independent laboratory quality tests of solar panels. Unfortunately, their testing is also limited due to companies included. To participate in their testing, a willing company must provide a participation fee. The biggest advantage is that the tests are rigorous and high-quality.

In most cases, manufacturers provide the following warranties: a construction/material guarantee and a power output warranty. The duration of the construction/materials guarantee may be up to 9-11 years. 

Power output warranty may range from 12 to 30 years (depending on the manufacturer). The power output warranty might state that a panel will still produce 80% of its rated output after 10 years and 80% after 25 years. So, it makes sense to choose solar modules with more than 70-80% capacity even after 2 or 3 decades.