Efficiency of Solar Panel , LED , Battery , Charge Controller

Solar Panel Efficiency:

The efficiency of a solar panel refers to the ability of the panel to convert sunlight into usable energy. Higher the efficiency, lesser the number of solar panels you will require to generate the needed electricity.

This type of solar panels are made of the highest purity silicon and they are the most efficient. They can convert a quarter of the sunlight they get into electricity.

This type of solar panels are less efficient than monocrystalline panels but they are also less expensive.

Factors Affecting Solar Panel Efficiency:

  • Shade

Solar Panel should be positioned in a clear area with no shade. If there is a shaded area the efficiency of the panels will be reduced.

Install the Solar Panel in the position which gives more hours of sun exposure to the panel to increase the effectiveness.

The efficiency of the solar panels decreases a little bit overtime.

Cleaning the solar panels regularly is important since dust or dirt can accumulate on the surface. This may block some of the sunlight and reduce the efficiency of the panels.

LED Efficiency:

The efficiency of a light bulb is measured in lumens per watt. LED lights virtually produce no heat (limited to 80%) in the illuminating process, therefore they are relatively cool. Approximately 20% electric energy gets transformed to light energy in these bulbs.

While in traditional bulbs, about 80% electric energy is lost as heat energy resulting on only 20% efficiency, that is, conversion to light energy. The most efficient commercially available LED lamps have efficiencies of 200 lumens per watt.

Battery Efficiency:

Efficiency of solar batteries refers to how much energy is successfully stored and converted to usable electricity. The efficiency depends on a number of factors including the rate of charging or discharging. Higher the rate of charge or discharge lower the efficiency.

  • The Lead Acid battery is not 100% efficient at storing electricity - you will never get out as much as you put in when charging. Overall, an efficiency level of 85% is often assumed. 
  • Lithium Ion (Li-ion) batteries are highly efficient. Li-ion has 99% charge efficiency, and the discharge loss is small.
  • The average efficiency of Lithium Iron Phosphate (LiFePO4) battery is 92% and the battery does not need to be fully charged.

Charge Controller Efficiency:

A solar charge controller is an electronic component that controls the amount of charge entering and exiting the battery, and regulates the optimum and most efficient performance of the battery.

The main purpose of the controller is to prevent the batteries from over charging. There are 2 types of charge controllers:

  • PWM (Pulse Width Modulation) Charge Controller

PWM controllers have the more basic charging feature. They mainly just drop the voltage coming from the solar panel to charge the batteries. This drop in voltage equates to a loss in wattage, causing 75-80% efficiency.

  • MPPT (Maximum Power Point Tracking) Charge Controller

MPPT charge controllers finds out at any given condition, what is the maximum operating point for the solar panels current and voltage. With this method, MPPT controllers are actually 94-99% efficient.