Remote power generation systems have used off-grid storage for many years in outback Australia. In most cases the system is built around a diesel engine generator with battery back-up. In more recent times, with the reduction in price of solar panels, a new type of hybrid remote power system has emerged that integrates a solar PV array with a battery. In most cases a diesel generator is still required because the battery itself does not have the capacity to store enough energy use for more than a day or so. The combined solar-battery-diesel hybrid yields a lower cost of electricity than a simple diesel generator because of the reduction in maintenance and shipments of diesel fuel.
Such systems typically require a solar array with matching inverter to convert the DC power from the solar panels to AC power.
A separate inverter-charger is needed to accommodate the battery. The inverter charger also allows the diesel generator to be coupled.
Example battery inverter-chargers are the SMA Sunny Island and the Selectronics SP-Pro.
Design and Install
- LC Energy has been involved in off-grid installations for many years
- We have installed a variety of systems; single and 3-phase
- reliability is critical for off-grid customers and is core to our designs
- system designs are flexible, highly configurable and can be complex
- typically, systems are installed with monitoring capabilities
There are two types of grid-connected storage system and LC Energy has installed systems that employ various battery chemistries, although lithium-ion is now preferred due to deep cycle capabilities.
1. Classical approach
This is essentially the same as the off-grid system except the diesel generator back-up is replaced by the grid. Batteries are typically charged by excess solar, and the stored energy used at night. Options are available to automatically separate from the grid during blackouts and maintain power in the home with battery storage maintaining some or all circuits until power is restored.
2. Hybrid system using inverters and batteries
Hybrid systems use a combination of a solar inverter and separate battery inverter/charger. The hybrid inverter/charger and battery set can usually be offered as an upgrade to an existing solar PV system.