Electricity + Control September 2019

ENERGY MANAGEMENT + ENVIRONMENTAL ENGINEERING

The distributed energy system at Siemens Midrand campus includes a 1 MW PV-solar power plant with solar panels mounted to the roofs of carports and the buildings.

Siemens Midrand microgrid demonstrates energy savings Siemens headquarters in Midrand today uses about 50% less energy from the national grid than it did just over a year ago when the company established a primarily solar-powered microgrid at its Midrand campus.

1. The project provides a showcase on a proven solution that will help save energy, cut costs, lower carbon emissions and ensure uninterrupted power. It presents a realistic case study for the South African context, and the results are convincing. Take Note! 1

O ver this period, by taking steps to reduce its energy usage and by using energy supplied via the microgrid, it has downscaled its consumption from the national grid by 2 435 000 kWh (2.4 GWh). That translates into 174 000 kWh per month, which represents 50% of the company’s normal monthly consumption. That 174 000 kWh saved per month is about the same amount of energy used by 50 average South African households over a year. This case study demonstrates savings on energy usage, energy costs, and the reduction of harmful emissions (2 460 tonnes CO 2 equivalent to date) that would otherwise have occurred had the company continued to draw its energy only from the predominantly fossil-fuel powered national grid. Bringing together the experience and initiative of local and global Siemens experts, this is the first Siemens distributed energy system (DES) solution of its kind in Africa. It is also the first that Siemens has installed in one of its own buildings. The project is aligned with the company’s goal to achieve carbon neutrality by 2030 – through energy efficiency improvements, the use of decentralised energy systems, the purchasing of clean electricity, and allied offsets if necessary. Sabine Dall’Omo, CEO Siemens Southern and Eastern Africa says, “The project provides a showcase on a proven Siemens solution that will help save energy, cut costs, lower carbon

emissions and ensure uninterrupted power. Everything from installation to operating costs has been tracked to present a realistic case study for the South African context, and the results to date are convincing. The DES solution installed at our office park serves as an active example of our belief in the solution and the sustained benefits it creates.” The system that has been installed at Siemens’ Midrand campus can be replicated and adapted to provide reliable and more efficient power to businesses, office parks, manufacturing plants, institutions and even small communities that do not have access to the national grid. Distributed energy systems The Siemens office park covers 22 351 m 2 and accommodates 800 to 1 000 workers daily. The DES solution is built around a 1 MW PV-solar plant with the solar panels mounted to roof the rows of carports as well as on the roofs of the buildings and equipment positioned strategically throughout the campus. Captured solar power is integrated into the microgrid controller. Excess energy is stored in a 140 kWh battery and the entire system is monitored, visualised and controlled via a Siemens engineered IoT (Internet of Things) energy platform. Distributed energy systems are an ideal solution for the African continent because they are designed to be adaptable. They also facilitate the

Electricity + Control

SEPTEMBER 2019

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