Posted on 01 June 2019

Alternative Efficiency

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By Arnold N. Alderman, Anagenesis, Inc.


In recent years two major efforts have consumed mega engineering hours of effort in the struggle to achieve improved performance. I speak of the efforts to achieve commercially viable alternative energy and the equal struggle to achieve improved efficiency both in conveyance and conversion. One is focused on the generation of electrical energy from renewable sources such as wind, sun, ocean waves, biofuels, and geothermal sources.

Arnold N. Alderman

The other is focused on getting energy to the load located in home, commercial business buildings, and industrial facilities. Although power supplies, motor drives and lighting ballasts have strived for higher efficiency for many years, recently the effort has taken on paramount proportions globally. Even with this effort, there is a good chance that the efficiencies achieved may be far short of that needed as alterative energy commences to become a significant portion of our energy source. Will 90% efficiency be satisfactory in that world?

I was fortunate enough to attend a workshop recently on efficiency sponsored by EPRI and PSMA in which opportunities to improve efficiency of the entire system from generator to IC was explored by a group of very qualified experts (1). Tremendous amounts of effort were being expended in both alternative energy and efficiency. However, it is becoming clear that converters such as power supplies, motor inverters, and solid state ballasts will have even greater demands for higher efficiency as alternative energy sources become a larger portion of the generation landscape. It makes entirely no sense whatsoever to struggle to increase the alternative energy generator efficiency when so much is lost before it gets to the IC, motor shaft, or lamp. In 2002 2% of energy developed was alternative energy. Today it is closer to 5%. Shell estimates that alternative energy growth will approach 30% of the generation landscape by 2050 (2).

As energy sourcing, energy conversion, and energy consumption evolves, designer and user perspective will change. Data center, home, and commercial building designers will no longer be able to assume they have an infinite power source. The generator source is evolving into a multitude of generating sources in both macro and micro generating grids.

Figure 1 shows all of the major elements in the power train from the primary alternative energy generator to the load, which in the case, is the data center. The main alternative energy generator can be one single generator station or a number of smaller generators connected together in a grid. The dynamics change considerably as the single source becomes a distributed number of smaller sources. By necessity, the converter dynamics will evolve into more dynamic high efficiency elements.

The entire alternative energy power train from generator to load data center load

They should be sharing ideas, concepts, and systemic solutions toward getting as much energy as possible to the loads. A “I don’t care what is at the other end of power network” attitude will not suffice in the following decades. There is too much to power to be lost. In fact that very point lead to the creation of PSMA and EPRI’s workshop in February 2007.

Distributed generation is a logical means of providing high levels of reliability to those who need it, without incurring the public capital outlay of providing it to everyone. Power supplies connected in distributed power architecture will not longer be viable. Too much power is wasted. Redundancy will morph well beyond the traditional parallel converter approach. Systemic reliability approaches will overcome the fear of bypass in UPS systems. Variable speed motors will be more widely used. Motors will once again transition to higher copper and iron content for better power factor and efficiency. All converters with rectifier inputs will have power factor correction. System efficiency well above 90% will become viable. That will become the alternative efficiency.

Image 2

To do less will be unacceptable for the alternative energy power source. Providing an overview to the energy industry, Denis Du Bois, CEO of marketing consulting firm P5 Group, stated, “Distributed generation is a logical means of providing high levels of reliability to those who need it, without incurring the public capital outlay of providing it to everyone. As businesses consider making their own electricity, they should take into account a triad of interrelated technologies — distributed generation, demand management, and alternative energy — that will be inseparable for years to come.“ I offer that “As businesses consider generating their own electricity, they should take into account FOUR interrelated technologies – alternative energy, distributed generation, demand management, and efficient POWER CONVERSION."



1) EPRI PSMA Energy Efficiency Workshop – From Generator to IC, Anaheim, CA, February 24, 2019, sponsored by the Electric Power Research Institute and the Power Sources Manufacturers Association (Workshop Report will be published in June 2007), (2) Source: Shell Global Scenarios.



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