The modern world is hungry for energy. Global electricity consumption has jumped from around 7,000 terawatt hours (TWh) in the early 1980s to reaching 30,000 TWh by 2024—growing on average 2.4% or around 700 TWh annually. In South Africa, electricity consumption has decreased slightly in recent years, but that is an anomaly caused by power production constraints. Up until 2008, demand in SA actually outpaced international averages and was four times the per-capita consumption of its nearest neighbours.

Energy pressure has put the spotlight on increasing generation, ideally through renewable resources. But there is another part of the energy value chain that is primed for a major step forward: the substation.

Substations are a crucial part of energy infrastructure, managing and converting voltages for safe usage. They are also traditionally very stoic and immovable assets. Building a substation requires considerable funds, engineering, and time, and they need regular maintenance and upkeep to maintain their accrued value. But after decades of service, many substations are not keeping up, and several industries are turning to alternatives called E-houses.

Substation limitations

A typical substation is constructed using bricks and mortar. This design made sense in the past to house the many delicate and dangerous components, ensure secure access control, and provide site longevity.

However, such substations have major drawbacks in terms of their construction and resilience, says Pervin Gurie, Director at WEG Africa: “When someone builds a substation, they build it to last, typically for 25 years or more. This process requires feasibility studies and civil infrastructure planning, which is time-consuming and involves different parties on-site at various periods. The structures need to be built correctly, such as using the right construction materials and curing the mortar to mitigate environmental factors. But even then, there are conditions that quickly wear down the substation structure, such as storms and humidity. Installing and testing components also add to the complexity. Overall, a typical substation is a demanding and expensive project.”

ALSO READ:
Energy on tap: Industrial turbines are steaming ahead

Such problems were less of an issue in the past, primarily because there weren’t viable alternatives nor major reasons to make a change. However, expanding generation opportunities and growing energy demands compel substations to modernise. Costs need to come down, and substations need capacity to accommodate more energy sources and other requirements, such as cybersecurity.

A new generation of substations

Fortunately, there are already answers to such substation issues. Heavy industries such as mining and oil & gas have run into traditional substation limits for some time. High costs, challenging conditions, and shorter timelines have created demand for alternatives, of which E-houses are the emerging winners.

ALSO READ:
Generators: The Muscle in the New Energy Mix

An E-house, or electrical house, is a prefabricated, customised, and transportable steel structure designed to house a range of electrical and automation equipment. Pioneered by OEMs such as WEG, E-houses are built to a customer’s specification, assembled and tested at the manufacturing facility, then disassembled, shipped, and reassembled at the customer site.

E-houses are quickly becoming the preferred substation. Last year, WEG’s Heidelberg facility in South Africa manufactured and installed E-house solutions at Sasol’s Upstream Production Sharing Agreement (PSA) Project in Mozambique. Measuring 45 by 22 meters, this E-house solution includes medium-voltage (MV) and low-voltage (LV) switchgear, a battery room, a local equipment room, and an HVAC system.

Such substations are also gaining popularity among mines, such as one local WEG customer that has produced over 20 E-houses for their operations. Heavy industries prefer E-houses because they are more affordable, scalable, and resilient than mortar substations.

“You can design E-houses to fit very specific conditions. For example, the E-house solution for the Mozambique project is reinforced to withstand hurricane conditions. The costs are also lower because all the planning and testing are done at the manufacturing facility before we ship and reassemble it onsite. We can also add specific equipment, such as generators and access controls,” says Gurie.

E-houses are not temporary solutions. They can permanently replace masonry substations. They also ship as semi-mobile and mobile substations, or as onboard substations on large equipment. Increasingly, E-houses have become sought after to replace substations for power generation, pulp and paper plants, water treatment sites, steel facilities, cement manufacturing, and general industry.

Substations for the 21st century

Modern energy demands are changing the requirements for electricity distribution. Costs, alternative generation sources, digitisation, and expectations for scale, mobility, and alterations reveal the limits of traditional substations.

Flexible solutions such as E-houses are filling this void. Their supply chains from manufacturing to installation support considerable employment, high-skill professions, and partner networks. It might be too soon to retire traditional mortar substations. But for many industrial and commercial users E-houses are delivering the future of electricity distribution.