This system is very similar to an off grid standalone system but has the ability to interact with the public power grid network. Eskom power could be used as a backup source of power when required. Such a system will automatically switch to Eskom power when no Sun has been available for a period of time or when electricity demand exceeds the ability of the system.
Depending on the size of this system and the appliances or devices requiring power, it can support an entire building or just specific chosen loads. The modular ability of solar systems means that a system could be designed to support only critical loads initially, whilst having the ability to expand capacity later through the addition of more components.
In areas with frequent power failures (as in South Africa), such a fully automatic, silent solar powered system is almost becoming a must! With proper initial design, future expansion that makes the user totally independent of their power producer, can take place as finances allow. A ballpark indication of cost for a fully installed turnkey system with top quality components is around R 15 000 per kWh (units) daily energy required. Final cost will depend on specific component choices, additional functionalities required and site specifics.
Main benefits of Grid interactive PV solar systems:
- Avoidance of outages and load shedding.
- Electricity provided by Sunlight.
- Independence from Eskom, partly or completely.
- Dependable and reliable.
- Cost of energy yield fixed for at least 25 years.
- Expandable and modular – system size can be increased at any time.
- Renewable resource with minimal impact on the environment.
- Automatic grid assistance when additional energy is required.
Main disadvantages of Grid interactive PV solar systems:
- Higher initial cost due to battery banks required (although typically smaller battery banks than for a standalone system could be utilized).
- Battery banks need replacement eventually. Depending on design and type of batteries used, a lifespan of 2 – 15 years is possible.
It is critical that the design of such a system be done by a professional. This will not only ensure that the system performs as expected and operates flawlessly but also that future expansion could take place without needing to replace key components, and that the modular ability will be technically feasible.
Please contact your nearest ALLSOLAR branch for more information on a solution that will suit your specific needs.