Battery Backup Solar System

What is a Hybrid or Battery Back-Up Solar Power System?

Is it common for the power produced by a solar power system to exceed the power being used during sunny periods. It may be a home where you are out during the day or there is simply less demand for power.

In a grid connect system, that excess power can be exported to the electricity grid, earning you a credit on your power bill. However, in most cases the amount paid for electricity exported to the grid is well below the price you pay when you buy electricity. So you may create power and sell it to the electricity retailer, only to buy back in the evening at a higher rate.

With an on-grid battery storage system, that excess power can be used to charge your batteries. When you use power in the evening you are drawing on the energy stored during the day and may not need to pay for electricity.

A second advantage of having a battery backup power system is that it provides you with a greater degree of energy independence. It becomes an ‘uninterruptible power system’ (UPS), so that if an outage occurs in the electricity supply your system automatically switches to the battery supply for continuous power.

What Do I Need?

Solar Panels

Solar panels are devices that convert light into electricity. They are called “solar” panels because most of the time, the most powerful source of light available is the Sun, called Sol by astronomers. Some scientists call them photovoltaics which means, basically, “light-electricity.”

A solar panel is a collection of solar cells. The more light that hits a cell, the more electricity it produces.

Solar Inverters

A solar inverter, or converter or PV inverter, converts the variable direct current (DC) output of a photovoltaic (PV) solar panel into a utility frequency alternating current (AC) that can be fed into a commercial electrical grid or used by a local, off-grid electrical network.

Solar inverters may be classified into three broad types

Grid-tie inverters – which match phase with a utility-supplied sine wave. Grid-tie inverters are designed to shut down automatically upon loss of utility supply, for safety reasons. They do not provide backup power during utility outages.

  • Battery backup inverter/ chargers
  • Stand-alone inverters

Solar Batteries

Solar batteries work by converting the AC energy being produced by your solar panels and storing it as DC power for later use.

The higher your battery’s capacity, the larger the solar system it can charge.