Go with the flow

We have discussed various methods of generating power at Raccoon Creek. After reading about wind power, studying the maps of reliable winds in the area, and recognizing the density of trees at Raccoon Creek, we decided that wind power wasn't a likely option for us.

Photovoltaics, of course, will always be in the mix. We will be siting our buildings for maximum exposure for solar exploitaion, both active and passive.

The power generation method that we still need to investigate more is micro-hydroelectric power. In general there are two schemes for generating power from water. One is situating a turbine at the end of a pipe that drops the water a sufficient height to spin the turbine and generate power. The other is to use a generator that looks somewhat like a propeller and is emerged into a flowing stream or river.

Raccoon Creek has ample continuous water flow, but across the entire property, even if we were to use the section that we don't intend to develop, the creek has only a fall (drop) of about 10 feet. And to make that ten foot fall useful, that is, to get much of that fall to occur within a short distance, we would have to run a very long pipe from upstream to a point near the buildings-to-be, a distance of up to a quarter-mile, and "drop" it onto the turbine. This would present other problems, like keeping the pipe from freezing in the winter, and the cost of supporting it over such a long distance.

That leaves us with the other type of generator, sometimes called a jack rabbit type. Though there is a lot of water in the creek, where it would be easiest to use, and closest to where we want it, the creek is from 15 to 25 feet wide and rather deep compared to other sections, maybe 5 feet in some places.

This wide, deep, stream section results in a very slow flow through that stretch. This type of generator requires a flow of about 8 miles-per-hour, and, as it is, we're nowhere close to that. If we can concentrate this flow into a smaller cross section, like a culvert, most of the flow will be available for power generation. If this can be done without adversely affecting the creek bank and without causing additional flooding during high water events, we will have a great, reliable power source.

The next steps are to accurately measure the flow, and then to contact manufacturers of this type generator for advice on how we might concentrate it. I'll report on progress on this front.