Off Grid Solar PV Systems Off Grid Solar PV Systems
Getting Off The Energy Grid
Off-grid Solar PV systems can be expensive and are not for everyone. Generally, off grid solar PV users are a different breed of energy consumers, utilizing a wide variety of energy saving methods to meet their overall energy needs--as opposed to your standard, suburban home energy user.
Choosing an off-grid solar system requires a radically different approach to energy consumption, and may not be right for every home owner.
Many off-grid solar users have solar water heaters installed as they are cheaper per kilowatt-hour than an off-grid photovoltaic system. Using a variety of energy sources can be a distinct advantage should a power blackout occur, as it ensures you are protected from power outages and Hawaii power blackouts.
It is also important to note a battery PV systems requires fairly consistent attention and maintance. The battery pack is the core of any off-grid solar PV system and will drive the overall cost for the system. A general understanding of how battery systems work is essential to extending the life of your battery pack system.
Here are a few of the most commonly used off-grid solar electrical system terms:
Charge controller: The charge controller feeds current into the battery bank at the required voltage. Good charge controllers draw the best performance out of the batteries and are very important for economics because they influence efficiency.
Battery bank: The battery bank is typically made up of six or more individual batteries connected with stout cables in either series or parallel arrangements.
Inverter: The inverter changes DC to AC voltages suitable for use with household equipment. An inverter is optional if you use DC loads exclusively.
DC loads controller: You may be using both DC (boat, RV, and auto appliances) and AC loads (standard household appliances). The DC loads controller maintains the proper currents and voltages into the DC loads.
AC generator: As a backup power supply, the AC generator isn't strictly necessary but is usually part of any off-grid system in order to prevent blackouts when the sun is weak for extended periods.
Transfer switch: The transfer switch alternates the power source between either the inverter output (when battery power is available) or the AC generator.
AC loads controller: This device includes appropriate fuses and switching means and maintains the voltages and currents used by the AC appliances connected to the system.
Choosing whether or not you want to run a AC or DC current largely depends on what you need to run in your home or business. Smaller load requirements can run on DC alone, however, most home appliances will require an AC current.