Energy Efficiency Made Simple Vol IV 2015

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Engineers… does the ‘Solar Sphere’ improve collection of solar power?

In the earliest electrical machines, solid iron cores were used, cast or wrought, but the benefits of lamination in reducing eddy currents rapidly became apparent. Higher magnetic grades of steel which improve efficiency must be included as a major factor considering the urgent need to diminish wastage of energy, conserve finite resources and reduce the release of pollutants. Improved higher grades of steel also enable machines to be reduced to more manageable sizes. Reduced size is clearly associated with reduced energy wastage in exciting conductors. In pursuit of a greener world there is a pressure and interest in pumps, fans and other drives to use speed control which improves efficiency and reduces waste. Speed control throttling of the output, a very wasteful practice, can be avoided. The means of speed control offers fresh challenges to the motor manufacturers to

accept a wide range of input frequencies without themselves creating excessive losses. High speed motors mean smaller and lighter machines, able to de- liver increased power output, lamination steel and Variable Frequency Drives (VFDs), critical to achieving these benefits. Transformer lamination steel In the past 70 years the development in lamination steel, as well as amorphous alloys, has reduced the losses significantly. Transformers for power distribution experience two pressures. The first is for reduced first cost to fit in with short term budgeting; the other is to be super efficient so the life time ownership costs are minimised and green performance optimised. In the early 1940s, losses in conventional grain-oriented steel at 1,7 Tesla were around

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ENERGY EFFICIENCY MADE SIMPLE 2015