Featured: EE Publishers

Tapping untapped renewable energy

  In water distribution networks in South Africa, water is often fed under gravity from a higher reservoir to another reservoir at a lower level. This provides an opportunity to generate renewable energy by passing the flow through a turbine. The high pressure head at the receiving reservoir is then dissipated through the control valves […]

Chandra X-ray observatory celebrates 15 years in space

  Fifteen years ago, NASA’s Chandra X-ray Observatory was launched into space aboard the space shuttle Columbia. Since its deployment on 23 July  1999 Chandra has helped revolutionise the understanding of the universe through its unrivalled X-ray vision. Chandra, along with the Hubble Space Telescope and Spitzer Space Telescope, is specially designed to detect X-ray […]

Twenty-first century distribution transformers

  William Stanley, working for Westinghouse is credited for building the first refined and commercially used transformer. In 1886 he used his transformers in the electrification of Great Barrington, Massachusetts, USA. This was the first ever implementation of an AC power distribution system using step up and step down transformers. Today, more than 120 years […]

Improving motor efficiency

  Some 20% of the estimated 65% of industrial energy used by electric motors is lost by wasteful throttling mechanisms, making it essential to reduce the energy appetite of motors. Energy consumption by electric motors can be reduced in two main ways – efficient control of the speed at which they run, and making the […]

Testing the limits of IEEE 802.11ac wireless networking standard

  The evolving wide-bandwidth IEEE 802.11ac communications standard brings new benefits to users but new challenges to those tasked with testing products based on this standard. As the IEEE 802.11ac wireless standard evolves, it continues to breed new challenges for those tasked with testing and measuring these wireless systems. As products based on the IEEE […]

Multiple appointments of mine surveyors a risky business

  The increasing trend in recent years to appoint mine surveyors to positions of responsibility over multiple mines is potentially hazardous for personnel working on those mines and is hastening the demise of the mine surveying profession just as it is most needed. In terms of the Mine Health and Safety Act of 1996 (MHSA) […]