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Energy Storage: securing clean energy in South Africa

Due to the increasing demand of energy, and climate change associated with the greenhouse gases from fossil fuels, the need for renewable energies such as wind and solar photovoltaic (PV) has been increasing. The price of wind and solar technology is becoming very competitive, and energy storage makes it a viable solution for delivering secure energy.

To achieve high levels of system stability, reliability and flexibility, renewable energies need battery storage to manage electricity supply fluctuations. In this study, the latest battery chemistry technologies have been discussed, evaluating their operating temperatures, discharge rates, cell voltages, recharging and discharging characteristics and their reliability.

The research also presents a comparative analysis between different grid connected hybrid electrical systems in Johannesburg, South Africa. The analysis was conducted using HOMER modelling tool, performing a techno-economic evaluation for PV coupled with battery systems as the preferred option for ensuring energy security.

This research provides updated information on various battery types, detailing their advantages and disadvantages and therefore potential applications.

The study also covers a financial comparison between lead-acid batteries and lithium-ion batteries in a hybrid electrical system, as well as an indication of the cost factors at play.

The assessment revealed that despite lithium ion batteries having a significantly greater initial capital cost than lead-acid, their levelised cost of electricity is much lower. This highlights the importance of considering the long term performance of these systems.

This research provides a link to new market opportunities in South Africa where energy storage is a vital component for energy security. The simulations undertaken use real data from the economic hub of South Africa, making it a relevant guide to decision making.

The research gives a full breakdown of the energy storage technologies available in the market, making it easier to advise clients on suitable storage solutions. It also contributes to the advancement of these technologies, which may ultimately lead to reducing the price of batteries. This would make energy arbitrage more feasible, and batteries combined with renewable energy will soon become an affordable option to deliver secure energy.