Solar Chargers


There are two ways of using solar energy, the direct consumption and storage.

Direct COnsumption

This is the difficult way, because the sunlight strong fluctuations, the high open circuit voltage and the weak or non constant electric current  lacks of the necessary condictions for many consumers. Because solar panels always provide DC voltages a AC conversion is mandatory.


Battery Storage

Caching offers several possibilities:

  • Retrieval performance when needed and regardless of the Sun.
  • Heavy-duty batteries provide more power.
  • Stable conditions for current and voltage.

For storage in batteries can happen directly with a charger or a solar charge controller.

Direct Storage

You can connect solar modules directly to solar-rechargeable batteries. but you give up the protection against surge / overload. This leads  to critical or hazardous conditions not only for the battery, but also for humans.

Storage with solar charge controller

Simple chargers provide protection for the charging battery. A protection against deep discharge also ensures long service life.

Here is a selection of protection functions:   

Overcharge protection, discharge, reverse polarity protection of the module, load and battery, reverse polarity protection by internal fuse, automatic electronic fuse, short circuit protection, overvoltage protection at module input, open circuit protection without battery, reverse current protection at night, overheating and overload protection, battery overvoltage shutdown

The disadvantage of these chargers is that the modules do not work at the optimum point of current and voltage (MPP) and the voltage of the solar module is reduced to the charging voltage of the battery.

The result is a waste of power, such to reconsider the cost / usage ratio of a cheap charge controller.

Storage with solar charger

Although many chargers are called "solar", those dispose of at least one function which makes a difference: the MPP tracking. In order solar modules to work, they are usually regulated by a so-called MPP-tracker (MPPT), to set the voltage to the required value. The MPP Tracker varies the current drawn by a small amount, calculates in each case the product of current and voltage, and provides a current value for a higher performance. This iterative process is constantly guided by a microprocessor so that is also present in varying exposure conditions (factor> 10 between the cloudy sky and sun) is always operating in the maximum power point. Performance improvements of about 20% are realistic, making possible cost savings in the module selection or shorter load times.