A solar panel rated 300 watt/24V on average only produces about 210-240 Watts (70-80%) of its rated power during daily use.
This is because, the rated power is generated under specific conditions of lighting and temperature found in the testing centers but unlikely to be found consistently at the places of installation.
To make up for this shortfall in actual power produced, solar panels are oversized. For example, if your appliances need 300W of power, plan for about 300/0.7 = 428W of solar panels to guarantee it.
The amount of energy produced by the panel during the day depends on the daily number of sunshine hours received by the panel.
Energy produced by a 300W solar panel
A 300W solar panel produces about 300Wh of energy in an hour. The daily energy produced by this panel is 1,200Wh calculated from:
energy produced in an hour x the assumed 4 number of sunshine hours for the location.
Amps produced by a 300W solar panel
A typical 300W/24V solar panel produces a peak voltage of about 32.2V and current of 9.32 A.
A 300W/24V solar panel has an area of about 2,520 square inches depending on the solar cell efficiency.
The size of a 300W solar panel
The actual size of a 300W solar panel depends on factors like solar cell efficiency, materials used for manufacture. For example a solar panel with 21% efficient solar cells is smaller in foot print compared to that with 17% efficiency.
Examples of 300W/24V 60 cell solar panel sizes on the market are: 64.57 x 39.06 x 1.57 in (1640 x 992 x 40 mm)
What can you power a 300W solar panel with
A 300W solar panel can be used to charge a battery bank provide power for appliances such as: laptop, LED lighting, cell phones, light electronics like a radio, drone, mini fridge and 32 inch TV.
The solar panel should be used to charge a battery bank and appliances connected to the battery bank using an inverter or a converter to:
- Provide safe and stable power for the appliance(s) unlike the power straight from the solar panels that varies with light intensity and temperature.
- Provide backup power to the appliances during the night when there is no sun.