Published on April 14th, 2011 | by Dawn Killough6
Green Building 101: Future of Hydro Power Is Small
April 14th, 2011 by Dawn Killough
When we think of hydroelectric power, we often think of large dams blocking rivers and generating large amounts of electricity. The future of hydroelectric, however, may be the exact opposite.
Think small scale generators on local rivers and streams providing power for communities. The new hydroelectric infrastructure will be less expensive, more efficient, and make less of an impact on the environment and wildlife habitat.
Smaller Hydro Power Is Better
Robin Wentzel of WENTZEL Environmental Contracting believes that large scale mega-dams are a thing of the past. Most current hydroelectric projects entail upgrading existing equipment or installing smaller “run-of-river” projects. In a 2006 report, the Idaho National Laboratory (INL) estimated that the US could increase its hydropower capacity by about 50% using run-of-river projects.
According to Wentzel, the environmental and aquatic impact of these smaller projects is usually minor when compared to large scale dams. These projects usually have very limited or no storage capacity, cause little or no upstream flooding, and generate power by diverting some of the water from a stream or river to the turbine and generator and releasing it back into the stream or river.
Economic Stimulus from Hydro Power Jobs
Pablo Solomon, an internationally recognized artist and designer, says that small hydro projects may be one way to help the US out of its economic slump. Projects “can be built and installed by relatively unskilled workers with basic tools and wheelbarrows. There are actually relatively large dams … in Texas built a hundred years ago with basically human muscle and mules. People have been diverting water and building dams by hand world wide for thousands of years.”
Solomon believes that hydroelectric power surpasses both solar and wind technology. The unpredictable nature of the elements limits the capacity of even large scale solar and wind farms. While rivers and streams do occasionally dry up, their flow is more constant, providing 24 hours of generation.
The Bottom Line of Hydroelectric Power
How much does hydroelectric power cost to develop? Wentzel estimates that large scale dam projects can cost up to $2 million per megawatt, if not less. Small run-of-river projects can cost $3 million per megawatt and up, depending on site conditions.
The problem with the large scale projects is that there aren’t many viable sites left that don’t already have power generation facilities. With no room for expansion, we are forced to look at less than optimum sites and install smaller facilities. Continued advances in technology may reduce development costs over time, however.
The Future of Hydroelectric Power Generation
Hydroelectric power generation may also find it’s future in the largest body of water – the ocean. Wave and current generation technology is making rapid strides and may soon be the standard. This technology, when used properly, can have a very limited impact on the environment, and projects are not as limited to specific locations like land based projects through the use of tidal currents, ocean currents and wave power.
Current costs for wave generation make most projects prohibitive – $3.5 million per megawatt. However, technological advances are expected to lower costs to $2.5 million in the near future.
Editor’s Note: Green Building Elements is launching a Green Building 101 Series which will be posted bi-weekly, on the 1st and 15th of every month. Take this challenge with us as we learn how to build sustainably from the ground up.