Sunday, April 26, 2009

Harnessing the Power of the Mighty Mississippi

Hydrokinetics can be defined as: “the branch of hydrodynamics that deals with the laws governing liquids or gases in motion.” [1] It is not a newly devised concept. Works discussing this topic date back ages, such as George Minchin’s 1892 work, Hydrostatics and Elementary Hydrokinetics.

Currently, there are numerous methods being used to harness the energy of moving fluids—including hydro-, wind-, and wave power. The use of in-river turbines, however, is a relatively young field and one that has been gaining some interest as of late. The first in-river hydrokinetic project just got off the ground within the last year. [3, 4]

The Mississippi River and its tributaries constitute one of the largest river systems in the world. As many as 31 US states and 2 Canadian provinces contribute watershed. Near the end of the river system, in New Orleans, the average flow rate of the Mississippi River is roughly 600,000 cubic feet per second—an equivalent of 166 semi-trailer truckloads of water each and every second. [2]

This massive volume of river water quietly roars by the Crescent City 24 hours per day 7 days per week, going unnoticed by many. In the last few years, though, numerous groups of people have tossed around the idea that the Mighty Mississippi may actually be capable of providing a very potent source of energy to be tapped. There are multiple proposed sites for hydrokinetic projects along the Mississippi River between St. Louis, MO, and New Orleans, LA. [5]

One of the proposed benefits to this alternative energy source is the lack of intermittency—the river is constantly flowing, albeit at varying flow rates. This is in contrast to the sometimes unpredictable stagnations in winds. There are ecological concerns, however, about what massive turbines could potentially do to local wildlife and fisheries in the river. Ultimately, however, not enough is known yet about this young field as to its viability as a clean, alternative source of energy.

[1] "hydrokinetics." Unabridged (v 1.1). Random House, Inc. 26 Apr 2009. Link.
[2] “Mississippi River Facts.” National Park Service, US Dept of the Interior. 23 Feb 2009. Link.
[3] “Hydropower – Industry Activities.” Federal Energy Regulatory Commission. 10 April 2009. Link.
[4] Thapaliya, R. “A MN city seeks approval to operate first in-river hydrokinetic project.” Hydropower Reform Coaltion. 27 June 2008. Link.
[5] Thapaliya, R. “In-river Hydrokinetics – Frequently Asked Questions.” Hydropower Reform Coalition. 21 August 2008. Link.


Toby said...

Very interesting. Yeah, a lot needs to be experimented and considered, but you are right, this is a great idea for harnessing energy of rivers.

Kelly Twomey said...

One of the huge ecological issues that the Mississippi River and the surrounding areas are being faced with right now is the exacerbation of the hypoxic zone of the Gulf of Mexico. This area at the base of the river is virtual incapable of supporting aquatic life and has been created largely by nutrient runoff from agricultural sources upstream (i.e. the Corn Belt). I wonder if there is anyway to collect or separate non-point sources of nitrogen (via. biological denitrification, duckweed, etc.) in tandem with power generation at one of these proposed turbine locations to reduce nutrient loading to the Mississippi River Basin.