Electric Vehicles In An Electric-Centric World- Part 4- Micro-Hydro

RENEWABLE ENERGY SOURCES

Now for the so-called "renewables". The "green" sources of energy to be discussed following include solar, wind, tidal and micro-hydro. Each of these power sources possess their own unique advantages and disadvantages. Let us now address them separately.

MICRO-HYDRO

Hydro-electric power is a large and potentially larger source of reliable "base-load" electrical power. However, it has serious environmental considerations to contend with. Large scale hydro systems disrupt ecosystems on a grand scale, and in some instances, are accused of creating ecological disasters and threatening endangered species [recall Tellico Dam, Tennessee; snail darter]. Such environmental disruptions have been witnessed at the Aswan High Dam that spans the Nile River in Egypt. This dam has been accused of increasing the rates of malaria and parasitic infestation such as liver flukes and schistosomiasis. The Three Gorges Dam located on the Yangtze River in China is another example. The loss of sediments that would otherwise naturally flow down the river and become deposited along the river bank during periodic flooding episodes is already being observed. This loss of soil replenishment contributes to poor, unproductive soils. As a consequence, the land will no longer be able to support the production of the same quantity of biomass per acre. In turn, the production of proteins which are essential to a balanced diet, and which a constantly growing population demands, will steadily decline. Exchanging a food source for energy is not an option that should be readily adopted.

Do not forget our own Hoover Dam that spans the Colorado River. The government recently discharged billions of gallons of water from behind the dam to allow accumulated sediments to flush out in order to rebuild sand bars that occur naturally in free-flowing rivers. Such sand bars are necessary to sustain the diversity of the natural ecosystem. Their re-creation by this release of water was a necessary component of the effort to restore native species of flora and fauna that have become endangered and/or were threatened by the absence of natural accretion and avulsion of accumulated river sediments. This action was more recently taken on the Glen Canyon Dam that spans the Colorado River.

No less a concern, an increase in mercury contamination of apex fish has been noted in flooded watersheds that are created by the impounded waterways. This contamination begins when plankton feast on decaying submerged vegetation; it ultimately works its way into and up the food chain to the point where humans ingest the contaminated fish and become ill. This dangerous situation is most critically established in Native populations located in areas that surround hydro-power watersheds found in the James Bay region of northern Quebec, Canada [e.g., Hydro-Quebec's Le Grande project most notably]. There, symptoms from mercury poisoning, including mental degradation and cognitive loss, were documented in many instances.

Moreover, increased siltation and sediment accumulation behind the dams are serious problems. Sediment accumulation causes it's own down-stream consequences; i.e., the concomitant loss of alluvial plain and enhanced erosion of the out flow/delta areas that do not periodically receive the sediments that are necessary to replenish them. This loss of delta habitat, particularly the marsh areas, reduces larval fish populations and causes the decline of other aquatic life. This loss ultimately inhibits the stability of mammalian and avian populations that depend on such habitat for food sources and nesting sites. The entire ecosystem becomes less fecund. The economic benefits derived from delta food sources [fish] and recreational use [hunting] are lost forever. These losses cannot be disregarded; they must be added to the cost side of the equation when the energy calculation is finally tallied. Our own Colorado River provides a lucid example. So much water has been diverted by major dams on this river system that the massive wetlands that once existed in the Sea of Cortez, and occupied the apex of the Baja Peninsula, have largely disappeared. Dried up and withered away. Bird life has vanished. The sea life that relies on the delta's estuary ["swamp"] for its very existence and survival has been reduced to a shadow of its former self. Here is where a vast breeding and nurturing ground once existed for fish, invertebrates, etc.

The sea is not as fecund as it once was; certainly it is not as commercially productive of the protein necessary to sustain our terrestrial population. That sea life continues to be assaulted from all directions and it is dying off at an alarming rate. A recent [2003] PEW Ocean Commission report estimates that a substantial percentage of the commercially-recoverable biomass in the ocean will have vanished by 2020. [http://pewtrusts.org/uploadedfiles/wwwpewtrustsorg/reports/protecting_ocean_life/env_oceans_final_report.pdf]. Further harm must not be visited on this resource by constructing more major hydro-power projects which will inevitably destroy additional vital delta wetland habitat.

Another assault on sea life occurs when the barriers created by dams -- such as those in Maine and in the western states of Oregon, Idaho and Washington [e.g., Grand Coulee Dam which blocks the natural flow of the Columbia River], prevent salmon and other species of anadromous fish [e.g., eels, shad, etc.] from migrating upstream during their annual spawning runs. If fish can not readily access their spawning grounds, spawning does not occur. Ergo, there are no fish. And species which survive on fish are decimated. The chronic affects of this blockage are highlighted by the declining and now paltry annual runs of salmon. Indeed, many environmentalists forecast that salmon runs in the western rivers will become "extinct" in the not-too-distant future. The consequence: salmon runs that are essentially non-existent, coupled with another permanent loss of protein that is essential for a growing population. Efforts to mitigate the effects of such blockage, such as capturing adult salmon and smolts, and barging them around the barrier, or building "fish ladders" so the fish can swim around the barrier, have been largely unsuccessful. The cost to make these efforts is also high.

We also see recent efforts to tear down aging dams in the Maine. The efficacy of maintaining large dams on the Columbia and Snake Rivers is also being re-considered. So, while dams are being torn down in the Atlantic/Northeast, and we consider removing them in the Pacific/Northwest, we should not find ourselves too reliant on massive hydro-electric projects to produce the electricity that a large population of plug-in vehicles will require. All of the stated environmental problems may be, and perhaps should be, avoided by using other sources of electrical generating capacity.

Mega-hydro projects, irrespective of their tremendous up-front capital costs, are quite costly in terms of their deleterious impacts on the environment and ecosystem. This source of energy creates almost as many problems as it contributes to benefits in the form of production of electricity. This is particularly so in the water parched regions of the Southwestern United States, where disputes over usage allocation has lead to regional bickering and local water wars.

Enter "small" or "micro-hydro" power. Micro-hydro is a much smaller version of larger hydro-electric power projects such as exists at Hoover Dam. In this process, the power project's infrastructure essentially shunts or diverts naturally flowing river water around cataracts [drops in the level of topography which creates rapids and waterfalls] through sluices into which turbines and generators are placed, rather than by creating barrier dams which substantially block the natural flow of river water thereby creating an impoundment. Adopting micro-hydro as a source of power to generate electricity is a far better course of action than building "scalable"or large dams. Micro-hydro plants ameliorate the large scale environmental disruptions that are caused by building and operating large dams, and they leave intact the natural flow, hence the natural ecosystem, of the affected river system. Micro-hydro has it's place in the energy equation, but it's full potential is constrained because of limited domestic venues [rivers] and limited diversion areas [cataracts]. Canada has vast resources to develop micro-hydro. Unfortunately, most of these potential sites are located in very remote and environmentally sensitive regions. Of equal importance, these potential sites will require transmission lines into poorly accessible areas, resulting in disruption of forest lands to build transmission lines along these natural waterways and increasing the project's up-front costs.

World-wide, micro-hydro projects sited near cataracts and falls located on rivers of the South American rain forest, such as the Iguacu, have the potential to produce tremendous quantities of electricity. However, disruption of the environment, including construction of transmission lines that will have to be placed in, and will run through, virgin rain forests, must be at the forefront of strategic considerations. And, such extra-jurisdiction projects will not provide the United States with energy security that can only be derived from domestic sources.

For all hydro-electric power projects, whether major or micro, it is worth noting the recent effects of heretofore unobserved weather patterns on regional precipitation levels. These strange weather patterns may be associated with, or implicated in, climate change and global warming. Perhaps it is too obvious to mention, but the volume of a waterway and its flow rate is always subject to and depends upon the quantity of precipitation that falls in a particular region over time. More succinctly put, the volume of a waterway is susceptible to droughts. Global warming has been charged as a suspected culprit in several recently experienced droughts. Witness the snow pack -- or more accurately the recent lack thereof -- in the Rocky Mountain region of the United States. A sharp drop in snow precipitation over the past decade in Utah, Montana, Colorado and Wyoming, has resulted in a co-extensive reduction in snow melt and runoff during the summer months. This phenomenon has caused a corresponding precipitous reduction in the volume of water running into the Colorado River drainage. Consequently, Lake Mead [which was created by the construction of Hoover Dam] is already down almost one hundred feet from maximum pool and it is presently at only 52% of its maximum capacity. If the mountain snow pack continues to melt at present rates, or that rate accelerates and the snow pack disappears [perhaps an ominous sign of global warming], that fact will profoundly effect our ability to generate electricity using hydro-power as the source of energy. Another prime example of such extreme lack of precipitation: the drought that plagued the southeastern United States in 2007, where impoundments in northern Georgia [Lake Lanier] virtually dried up. One more highlight: the level of Lake Okeechobee in Florida has dropped dramatically. Witness too the evaporation of the Aral Sea in Kazakhstan. Such situations will become more common place and more exacerbated should global warming proceed unabated. Thus, micro-hydro power is hostage to the same environmental variants as its larger counterpart [i.e., sufficient water flow, drought conditions, etc.].

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