The Developer’s Perspective

Imagine for a moment that you are the lead member of an electrification committee in a rural community of a developing country, exploring the possibility of electrification. You, along with the committee, research rural electrification (RE) options for months, trying to find a balance between costs and benefits. During the committee’s decision-making process, two options materialize, representing two common forms of RE. The first option is a low voltage (120V – 600V) electrification scheme. Generally, lower voltage has safety and transformer price benefits, but higher power losses and cable costs. The second option utilizes medium voltage (1kV – 33kV) transmission. Here, gains follow from lower power losses and smaller cable sizes, while the transformers are larger, the poles are wider in diameter and taller and medium voltage is considered.

Now, keep in mind that RE is only one of many social priorities vying for the community’s limited resources, which means that the committee must consider overall price as a very important factor. The committee also understands electrification could induce increases in important economic and social aspects of life, but it is not sufficient for these conditions. Is there an obvious choice here? For many communities, the costs limit a committee’s choice to ‘none of the above’. Is there another, cheaper way to conduct RE? Is there a third option?

We believe we have designed a third option. It starts with a new power distribution transformer design we call the Microformer. The Microformer has energy savings, resource reuse, cost, and size benefits. First, the Microformer transmits electricity using medium voltage, single-wire earth-return transmission. At 2.4kV, this transmission reduces power losses, thus increasing efficiency compared to losses incurred at a lower transmission voltage. Second, the Microformer is built using a transformer from a post-consumer microwave oven. This reuse of materials extends the use phase of the microwave oven transformer (MOT) – the central piece of the Microformer – thus decreasing the transformer’s overall environmental impact, specifically regarding energy use. This reuse displaces the need for energy to be expended making new transformers.

Why is a third option for the committee so important? Electricity usage in developing and developed countries is very different, but in many cases the same components for electricity distribution are used. In Nepal, for example, one rural electrification project found that peak power was about 90 Watts per consumer or about 65.7 kWh maximum per consumer per month [1]. Meanwhile, the electricity consumption per consumer in Wisconsin is 710 kWh [2] or over 10 times the amount of a villager in Nepal, at the minimum! These two different situations call for two different electrification methods that maximize transmission voltage and power demand. Unfortunately, only one design solution is used to address both situations.

References:
[1] Inversin, A. “New Designs for Rural Electrification.” National Rural Electric Cooperative Association. 1994.
[2] Energy Information Administration, US. “Average Monthly Bill by Census Division and State 2008.” Accessed Mar. 15, 2010. Link
 
Copyright Microformer 2011