Just like in hot solar domestic water heaters, for solar energy to convert to electricity, it needs solar electric collectors. Solar electric collectors, convert solar radiation directly into electricity. Solar electric collectors can either be modular or laminate. When solar energy is converted to electricity, it is in direct current form. Therefore an inverter is used to convert DC power to AC.

Solar panels
How much does a solar panel cost?
OFF-GRID ELECTRIC SOLAR SYSTEM
HOW DOES AN OFF-GRID SOLAR SYSTEM WORK?
SYSTEM COMPONENT OF AN OFF-GRID.
GRID-TIED SYSTEM WITHOUT BACKUP.
SYSTEM COMPONENTS OF A GRID-TIED SYSTEM.
GRID-TIED WITH BATTERY BACK UP.
SYSTEM COMPONENTS OF A GRID-TIED WITH BACKUP.

Solar panels

The collectors are made from either monocrystalline or polycrystalline cells. Mono and polycrystalline modules are the majority of solar modules on the market.

Polycrystalline electric collectors are more popular and less expensive than a monocrystalline modules. When a semiconducting material is protected by glass and is not flexible it is called a module. And when it is protected by a flexible cover it is called a laminate.

How much does a solar panel cost?

Solar energy is the conversion of sunlight into usable energy forms: Solar photovoltaics (PV), solar thermal electricity and solar heating and cooling are all well established solar technologies.

There are basically three types of domestic solar electric systems.

Off-grid
Grid-tied without batteries
Grid-tied with backup batteries.

OFF-GRID ELECTRIC SOLAR SYSTEM

An off-grid solar electric system is one that solely depends on electricity supplied by the solar array.

HOW DOES AN OFF-GRID SOLAR SYSTEM WORK?

An off-grid solar electric system uses solar electric modules to charge the battery banks through a charge controller. The DC current from the batteries can be converted to AC, using an inverter. Or the DC current can be used directly. This is possible when all loads connected in the house use DC.

SYSTEM COMPONENT OF AN OFF-GRID.

SOLAR ELECTRIC ARRAY
CHARGE CONTROLLER
BATTERY BANK
DC DISCONNECT
MODIFIED SINE WAVE INVERTER
AC DISCONNECTOR
MAIN ELECTRIC PANEL

GRID-TIED SYSTEM WITHOUT BACKUP.

This is a domestic solar electric system that is connected to the main utility company’s electric grid.

Grid-tied systems supply AC electricity into the main circuit breaker box(Distribution board). That is also serviced by the utility power company. This makes it easy for the house to get power from either its solar electric modules. Or when this is not possible, from the utility grid.

It is important to note that in this system, the inverter that converts DC electricity from the solar arrays to AC electricity constantly monitors the quality of power from the grid.

Should the power quality from the grid go down or below a certain standard. The inverter shuts down automatically. Until the power utility quality is stable, for about 5 minutes. This feature helps protect utility workers who may be working in nearby areas.

SYSTEM COMPONENTS OF A GRID-TIED SYSTEM.

SOLAR ELECTRIC ARRAY
DC DIS CONNECTOR
INVERTER
OUTDOOR AC DISCONNECTOR
MAIN ELECTRIC PANEL
UTILITY METER
AC UTILITY GRID

GRID-TIED WITH BATTERY BACK UP.

In the grid-tied solar system with battery backup. The battery backs up supply power to critical loads when the utility power fails. This system is ideal in areas where load shading and utility power failures are common.

A grid-tied system with battery backs up supplies AC electricity. The main electric panel is also serviced by the power utility company. The house can get its power supply from its solar module or the utility company.

When utility power fails. The solar electric system switches from the main electric panel to supply AC power to separate the critical load panel.

SYSTEM COMPONENTS OF A GRID-TIED WITH BACKUP.

SOLAR ELECTRIC ARRAY
CHARGE CONTROLLER
DC DISCONNECT
TRUE SINE WAVE INVERTER
OUTDOOR AC DISCONECTOR
CRITICAL LOAD ELECTRIC PANEL
MAIN ELECTRIC PANEL
AC DISCONNECT
UTILITY METER
UTILITY GRID

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