South Africa has the highest electricity consumption in the sub-Sahara region and demand continues to outpace the installation of generation capacity. Similar problems exist among several other economies in Africa, Asia, South America and other parts of the world. An uninterruptible supply of electrical energy is important to all customers but more especially to commercial customers and those industrial customers operating manufacturing facilities on a 24/7 continuous production basis.
More than 1.3 billion people living in remote parts of the world either have no access to electricity at all, or have access to limited and/or unreliable electricity sources. As the global population increases and energy-sensitive lifestyles accelerate. There is an ever more dependence on reliable supplies of electricity to power these lifestyles. Rising to this challenge, governments around the world are investing in infrastructures to help deliver electricity to poorly-connected areas.
Power shortages, fossil fuel price volatility and environmental concerns have resulted in a search for sustainable solutions. This challenging problem can be met by taking advantage of the availability of renewable energy sources (RES) such as wind, solar that can be connected to the existing grid to improve supply reliability. One solution is the introduction of microgrid technology that is now being used by remote communities, islanded electrical networks, industrial estates and university campuses. This solution can provide a stable, cost-effective continuity of supply in addition to minimizing the environmental aspects. This is not a futuristic possibility, but field proven technology solutions currently available have been in operation in numerous installations around the world for the past fifteen years.
ABB have developed the ‘Microgrid Plus System and the PowerStore solution that offers continuity of supply when the customer loses supply from the utility network. The microgrid will also maintain its stability during the transition from the network to island operation. This technology has full on-and-off grid functionalities therefore maintain the power supply during network outages enabling industrial customers to maintain cost-effective and efficient production.
The Microgrid Plus System is a specially designed distributed control system that ensures efficient and reliable power flow management in order to reduce energy consumption and fuel, optimizing the use of renewable energy. This management system guarantees optimal loading of fossil fuel generators and spinning reserves. The system is modular-based and the distributed logic of the system will enhance reliability and scalability for the any future expansions.
The PowerStore is a compact and versatile grid stabilizing generator that stabilizes the power system in the event of fluctuations in frequency and voltage. To maintain the frequency and voltage the system stabilizes electricity networks by rapidly absorbing/rejecting power. The battery used includes state-of the art inverters and virtual generator control software and this solution is applicable to islanded grids or in grid support mode.
Microgrid Installation in South Africa
The microgrid installation in South Africa is installed in the ABB Longmeadow facility has an area of 96.000 sq.m (1,032,960 sq. feet) that serves as the Company’s South Africa HQ. that together with a manufacturing unit has some 1,000 employees. The microgrid installation comprises a 1MVA/380kWh PowerStoreTM, a battery package and Microgrid Plus, ABB’s dedicated control system for microgrids which together with a 75 kW rooftop photovoltaic (PV) field which has been added to the existing back-up solution. The microgrid technology at this plant is fully containerized and pre-designed for this specific application.
A cloud-based remote service system will be deployed for the operations and maintenance of the microgrid. This infrastructure for remote access gives the ability to have an overview of a fleet of assets in one common platform and the software tools for diagnostic analytics help to improve the overall availability and reliability.
This solution supplies the power demand of ABB’s factory and offices by using renewable energy, even in the event of load-shedding. It has full on-and-off grid functionalities and prioritizes renewable energy before using the existing diesel generation. This solution reduces the CO2 emissions by over 1,000 tons/annum providing cost-effective access to high quality energy while the minimizing environmental impact thereby fulfilling the energy requirements traditionally supplied by diesel generators.
Uninterrupted Power Supply
The integration of renewable energy like solar or wind combined with the Microgrid Plus System and PowerStore installation enables continuity of supply when the main power supply is disrupted. Additionally the supply will also maintain its stability during the transitions from grid to island operation. By utilizing this technology, buildings, offices and factories can maintain normal operation through any power outage enabling increased productivity, security and cost efficiency.