Hoover Dam, also sometimes known as Boulder Dam, is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Arizona and Nevada.
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Imagine what our economy would be like if almost half of our electricity came from renewable energy resources. No fuel price shocks, no foreign control, no worries about climate change—just clean, abundant, affordable electricity.
Before World War II, Americans actually lived that way, thanks to hydropower. The massive public works projects undertaken during the Great Depression built a fleet of huge facilities on some of the country’s biggest waterways. Job creation, electrification and inexpensive power modernized the rural South and helped to industrialize the West.
Then, the story goes, after the war ended and the atomic age began, hydropower growth slowed to a trickle. A myth that hydropower couldn’t expand any further gained currency. Well, get ready for some myth-busting.
Hydropower is the largest renewable resource in the U.S., providing about 8 percent of the nation’s electricity. Analysts say that capacity can double in 30 years, rivaling the growth predicted for the nuclear power industry and at a fraction of the cost. The Federal Energy Regulatory Commission is reviewing more than 30,000 megawatts’ worth of new projects, equal to a third of all existing hydropower capacity and big enough to power the New York metropolitan area.
Surprised? Many people are, because they still think of hydropower only on a scale of the giant Hoover Dam. The fact is, new technologies are creating ways to generate electricity in all kinds of waterways. For example, turbines that rotate slowly like underwater windmills can sit in rivers, aqueducts or other locations where water flows freely. Other units in oceans or tidal waters generate electricity as they bob up and down.
Even existing dams hold promise for energy production. Only about 3 percent of the country’s 80,000 dams generate electricity. Power-generating turbines could be added to many of these structures. The hydropower industry is encouraging the federal government, which owns many of these nonpowered dams, to begin assessing the potential.
Beyond that, engineers are finding ways to generate more electricity at existing hydroelectric dams by installing more efficient turbines and other technologies. The Grant County (Washington State) Public Utility District is almost halfway through a project to replace 10 turbines at its Wanapum Dam that will increase the facility’s capacity by more than 10 percent. The new turbines, developed through a public-private partnership, also offer a more “fish friendly” design.
Projects such as this one that maximize efficiency and reduce environmental impact are starting to attract support from environmentalists, who appreciate hydropower’s ability to provide reliable, affordable energy resources without greenhouse gas emissions.
The U.S. hydropower industry is pleased to see the Obama administration take a closer look, and we’re urging officials to invest in federal research and development that can propel new water power technologies to market. As the administration examines public works projects that can jump-start the economy, it should consider hydropower initiatives, just as its predecessors turned to hydro development during tough economic times 75 years ago.
The industry is also asking Congress to ensure that such development receives the same tax incentives given to other renewables. Hydropower should be part of state and federal policies, too. From renewable portfolio standards to comprehensive energy and climate strategies, hydropower offers a proved resource.
Note: This article was originally printed with the title, "Time to Think Hydro".
This article was originally published with the title Time to Think Hydro.
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31 Comments
Add CommentHydropower generated from existing infrastructure and augmented by new technology is great.
Reply | Report Abuse | Link to thisWhen it comes to building new dams, diverting rivers and creating great new lakes there are other issues that need to be addressed. Brand new great masses of water stress the mantle and could result in earthquakes, not proven but possible.
More importantly consider the effects on other species, loss of life from inundation of vast tracts of land, loss of already scarce habitat, isolation of small groups of animals, the list goes on..
Further consider silting and similar issues with dams, plus you are going to need an awful lot of concrete. Manufacturing concrete releases a lot of carbon dioxide, besides the impact of mining the limestone.
Lets start looking at the full picture, increase forest cover, generate more basic food from photosynthesis, increase biodiversity, and generate energy from solar, wind, flowing water, geothermal, tides, methane, the gravitational effect of the moon and any other of a myriad of other sources.
Hydro power is good but with changing climate, can we be sure of getting enough rain in the right places to sustain it?
Reply | Report Abuse | Link to thisI think wave power is better option for sustainability, even though its not directly available to all areas, the grid could be modified to cope...
SCIENTIFIC EARTHLING, you need to go back and actually read the article. Your second, third, fourth, and fifth paragraphs are just right out and out stupid. You cannot just read the headline and make an intelligent comment. I imagine these coal and oil idiots will make a comment almost word to word to your comment.
Reply | Report Abuse | Link to thisHydropower is just one of our SMART renewable powers that this article is bring to our attention and I wish this administration great speed in bring hydropower back into use. If we had continued to develop renewable sources for electricity and continued to develop electric vehicles 75 years ago, we wouldn't be held hostage by oil and coal today.
Great article ScAm.
I don't really expect political advocacy in Scientific American articles, but that's all this is - a one-sided false promise of utopian energy independence. The author forgot to mention the environmental impacts of damming - devastated fisheries, flooded eco-systems and ruined flood plains and deltas. But who cares - we don't want facts ruining a good story.
Reply | Report Abuse | Link to thisHeres a grate idea. Put paddle wheels in the bowl of peoples crapper-trappers. Then feed them some beans. Then when they go crap and flush it, the water spins the paddle wheels to generate electricity. 300 million people in america and growing. Just think, If every crapper-trapper had one and it could produce 1 watt of jucie, that would equil 300 million watts of jucie a day. What a boost to the grid. haha Yes. I know. I'm nuts. haha. Heres a better one, Pay people to turn a turn-style thats geared up to turn a generator. This would create jobs, create energy, provide a wieght loss gym for fat people, and cure global warming, all at the same time. In any case, just remember one thing, The government doesn't really care about global warming or the energy crisis. They want money. Your votes never did count. The worlds wealthest decides who is going to be the next winner. Not the publics votes. Whom ever has the most money makes the rules. This thing about hydro-power, is as old as the hills are. They have known this for years and years and years. Some of mankinds first machines were powered by running water back in the 18th and 17th century. Then some neanderthal put fire under the water to run machines and now people act like hydro-power/steam is some kind of new idea or a re-invention of old technology. And this is supposed to make us happy and excited? Talk is cheap. I'll be impressed when some one deploys it into action.
Reply | Report Abuse | Link to thisLiving in the Pacific Northwest, I'm accustomed to getting a lot of electricity from cheap, relatively clean hydropower. This article, however, glosses over the negative sides of dam projects: decimated fish runs, drowned valleys, lost ways of life, altered water availability, opening relatively untouched areas to increases in traffic and development, etc. We wrestle with the effects every day in this part of the country. Wise, more efficient hydro, yes. An uncontrolled spurt of dam-building, no.
Reply | Report Abuse | Link to thisscientific earthling
Reply | Report Abuse | Link to thisI agree with James Davis. Most of your comments are not specific to the article; and too general to debate.
1. Loss of Life from inundation of vast tracts - hydropower can be built small or large; it can be built as run-of-river with a very small dam,e.g., at a lock & dam on the Ohio River. When large dams are built, many times the electrical power generation is an ancillary aspect because the dam is built for flood control, agricultural irrigation, or municipal drinking water supply. Naturally there are some trade-offs as with any large structure.
2. Loss of already scarce habitat - Most large dams, such as Hoover or Grand Coulee, were built in unihabited areas that were desert habitat. Considering the benefits of both Hoover & Grand Coulee for irrigation, power generation, drinking water, and recreation where water is a scarce commodity; I don't see your point on loss of habitat when dams are built in unihabited areas that are a desert environment.
3. Isolation of small groups of animals - Can you be any more generic. Please identify which group of animals; how they were affected by the dam, or did they just relocate on their own; and detail the benefits to the humans in the area in comparison to whichever group of animals you are talking about.
In general, I agree with this article. There are over 80,000 existing dams in the U.S. used for irrigation, flood control, municipal drinking water supplies, etc. ; and only 3% of these dams are used to supply electricity. Let's try to utilize more of the exisiting dam structures to generate electricity. In this way, we obtain electricity from a renewable resource with zero emissions while minimizing the number of large dam structures that must be built.
Hydro and Wind, its all we really need. I lived on a sailboat for many years and relied on wind generators! Very effective!
Reply | Report Abuse | Link to thisRT
www.anon-tools.cz.tc
James David.
Reply | Report Abuse | Link to thisI do read articles from start to finish.
I am writing against large dams. When you build a large dam as China did, the water level rises slowly, animals move to higher ground, often this land becomes an island and is then inundated, can you now see how these animals die. Remember there is much more life than these large animals there are trees, bushes shrubs,weeds, all forms of arthropods, our soils are full of worms. I don't suppose you care but they are necessary for us to survive.
Large dams always silt up, and their capacity reduces as silt is deposited. When it comes to cement, where do I begin? Mining the limestone, making klinker, grinding klinker. Been there!
Man is not the sole occupant of this planet. He exists because of the other life forms that went before and others that provide him food and clean up his wastes. Since his ascendancy he has eliminated species not just by killing but also by depriving them of habitat. What most of our species do not seem to realise is that we dependant on biodiversity for our survival.
Love your idea about electric cars, but who killed the electric car? People who don't look beyond tomorrow.
My opinion of coal. Stop its use NOW and stop Mercury pollution of our seas. Mine the methane held by coal as a stop gap source of energy.
We need oil for chemicals, don't burn it as fuel.
Hydroelectricity generated from water stored in large dams cause land degradation. Talk to a farmer affected by salinity and rising water tables.
Above all else control our population growth.
David M Clement.
Reply | Report Abuse | Link to thisYes I am speaking in general about the flip side of large hydroelectric projects. I have no problem at all with small hydro electric projects undertaken with care. Don't create a water flow that erodes the land and creates deep chasms that drain the water table.
I have been very specific about future dams, not asking for existing large dams to be shut down or demolished.
When I talk of life I include everything include microbes. You will find life exists everywhere on our planet. We need biodiversity to survive. The most insignificant species contributes to the stability of our biosystem.
I do not mean creation of Galapagos island scenarios. As water levels rise animals large and small move to higher ground, this does not necessarily mean the shores of the newly forming lake, but to high spots that are soon inundated. They were always living there.
Take a trip to Australia and check out our mighty Murray and Darling rivers, see the impact of Cubby Station's weir. Yes we have big hydro electric projects in Auz. The snowy river project seems successful and does not seem to impact the environment harshly.
What about the salmon, shad, eels, striped bass and other such migratory fish? What is wrong with nuclear power?
Reply | Report Abuse | Link to thisHydroelectric power dams are very LARGE producers of greenhouse gases according to some studies. The land that has been covered with water produces methane gas (far more potent than CO2) at a high rate for a long period due to the buried plant matter beneath the water. If there were no dam there, the plant matter would just turn into CO2, and much would be absorbed into the natural carbon sink - the forest that no longer exists.
Reply | Report Abuse | Link to thisSo hydroelectric dams are not green, though they are a renewable energy source.
Since most dams do not exist for power generation, there is certainly an untapped resource there. The methane will be produced regardless.
Many dams cannot be used, though because they are built to contain water - for drinking water reservoirs, to prevent flooding, or to divert water from structures. Some of them allow water to flow - these can be tapped. However, the many dams whose purpose is to prevent water from flowing are unuseable.
The author of the article may be jumping the gun and assuming that more dams are available for power generation.
I do like the idea of using free-flowing streams to generate power. This has been tried before and usually fails due to corrosive materials (salts) and aquatic life that grows on the turbines, clogging them or reducing water flow. The maintainance becomes exhorbitant, even if there are no moving parts as in the example of the magneto-hydrodynamic (MHD) power generators which generate power due to the flow of water molecules (which act as tiny magnets on their own). The power is reasonable for a time, but the flow of water is quickly reduced.
@U.S. Citizen: actually, water power got a huge boost in the 12th & 13th centuries. Manufacturing was driven by huge water-powered "factories" pumping out grain and paper on a scale never before seen. It was a medieval industrial revolution (yes, stolen right from James Burke).
Reply | Report Abuse | Link to this@scientific earthling: while I agree with you to a point, you're missing one important aspect: how much harm is being done by NOT using hydro power? How many species are affected due to climate change and pollution from fossil fuel usage? Biodiversity is important, but we're not going to get ourselves out of this mess without making some difficult choices. If the choice is I affect the habitats of a couple of local species of fish or I irreparably damage the oceans and potentially thousands of species, I'm gonna have to go with the former choice. There are NO perfect solutions, but as the article states we have the potential of making a huge impact on our energy consumption without making as huge an impact on the environment as we would've in the past. We know more about the impacts of damming since Hoover was built and incorporate minimizing those potential impacts into design. Also, the article specifically states taking advantage of already existing dams. If they did cause any environmental damage, it's already been done. Nothing we can do about that. But, if those can provide clean power...so much the better!
US Citizen...ahahaha! I love your ideas.
Reply | Report Abuse | Link to thisI've been telling people for a long time that we need to install bikes and tred mills in all the prisons across the US to generate power. What else do inmates do aside from eat, sleep, and exercise? It would be perfect. We could even provide them incentive by reducing their prison sentence in relation to how much power they generate....gets prisoners out of the system, and generates clean energy. Twice the bang for your buck!
Pick your devil. They all have impacts and unknowns. As our knowledge expands we address the issues as they are realized. In my view, humanity needs to go low impact and it will be done in a realm of uncertainty or nothing would ever get done if full certainty was required. Every energy conversion techology has issues. It is useful to examine the impacts of a monolithic energy conversion strategy using various energy conversion technologies. That being all wind, all solar, all hydro, all nuclear, etc. It highlights some of the issues of things going forward. I ran all these numbers - it was interesting.
Reply | Report Abuse | Link to thisAnyone who just says "No" to anything is living in a dream world or has a counter interest. In my estimation the lowest impact energy conversion system is a hybrid of intermitent sources (fuelless), some base load and distributed grid storage - consumer arbitrage - smart meters with buy and sell triggers based on instantaneous price and some fridge sized appliance that can store say 50 KWhrs for a residence. Then there is much reduced prejudice with respect intermitancy.
My take on the number one priority should be to make the grid neutral on source and commencerately figure out some way to change the finacial motivation of the grid operators so they get paid, not based on return on capital, but rather on gdp/unit of energy. I have no clue how to pull that off or what exactly would be a suitable proxy metric that might be measuerable and implementable. But at least then the grid operators would be incented to advance conservation and efficiency as opposed to build more things and hence employ more capital which they would get paid on.
It would be helpful in advancing in this direction if economists would realize that an economic transaction has two essential entities: Energy & desire. It isn't an accident that the core inflation has energy and food removed. It isn't because they are volitale it is because they are the inputs that drive all economic activity. To pull thisoff all they need to do is change the conventional definition of money by adding one additional property to money: The ability to allocate/endorse an expenditure of energy.
t34ch34
Reply | Report Abuse | Link to thisI don't know where you get your data concerning methane emissions at hydro dams. There have been some very bad data put out by environmentalist groups that are biased against dams. The most recent data I have comes from the Goddard Institute for Space Studies (http://icp.giss.nasa.gov/education/methane/intro/cycle.html) which shows in their "Global Methane Study" that wetlands (environmentalists favorite) produce 22% of the worlds methane, rice paddies 12%, Coal & Oil Mining, and Natural Gas Production 19%, and the worlds oceans 3%.
So my question to you is: Where did you get your information? I've worked in the hydro industry for 30 years; and know that there is no internationally acceptable standard for measuring GHG emissions from large reservoirs. At present, depending upon the measurements and monitoring techniques used, and with no agreed upon standard, anyone can prove anything depending upon what assumptions they make (Reference "Greenhouse Gas Emissions from Reservoirs: Studying the Issue in Brazil", HRW magazine Dec 2008). I also know that Manitoba Hydro and Hydro Quebec are presently using automated systems developed by the Department of Fisheries and Oceans of Canada to determine how much methane is emitted from some of their large reservoirs. These are "custom made" devices because no measuring devices are presently in existence for this purpose.
In conclusion, where do you get your data that hydroelectric reservoirs are large producers of methane emissions? And what "acceptable" measurement techniques have you used?
And finally, if the oceans only produce 3% of the methane gas in the world; exactly what percentage could a large reservoir produce?
David M. Clement:
Reply | Report Abuse | Link to thisYou should have mentioned before you were involved in the hydro industry for 30 years, it creates bias. Me I have worked as an industrial chemist and engineer since 1970, so you know my biases.
I once supported hydro-electricity blindly, remember the proposed Franklin dam in Tasmania, Australia. I saw it as a non-polluting source of electricity. I was wrong. I learned always to look for the down side.
To answer your question about methane from dams please go to:
http://internationalrivers.org/en/node/1398
Large shallow lakes emit the most methane.
Relhager said: "This article, however, glosses over the negative sides of dam projects: decimated fish runs, drowned valleys, lost ways of life, altered water availability, opening relatively untouched areas to increases in traffic and development, etc."
Reply | Report Abuse | Link to thisOK, fish runs are definitely affected negatively, although palliative measures are available. I wonder, though, in the long run if ocean awarming due to climate change -- enhanced by conventional energy production -- might not prove to be even more harmful to traditional fish stocks.
As for drowned valleys....ummm...that's what ALL existing rivers are right now. Surely you are not suggesting that rivers themselves are bad things. Lost ways of life can also come about because of a lack of irrigation water, as many farmers in the Central Valley of CA are discovering. Inability of poor people to keep up with rising food prices also constitutes a loss of something -- maybe life itself. Altered water availability? You mean ENHANCED water availability, don't you? Isn't that why, as you fear in your last point, that people will flock to these previously-barren lands?
I'm also a little baffled by constant references to the loss of CO2-fixing vegetation when valleys are flooded. Hasn't anyone heard of phytoplankton? I'd be willing to make an unscientific wager that the total biomass of, for example, Lake Mead is vastly greater today than it was as an arid desert valley system. And if methane is such a threat, shouldn't we drain all existing wetlands ASAP?
And how about the evaporative cooling and rain-making effects of large water impoundments -- aren't those good things in an age of global warming?
I can understand -- and even sympathize with -- the commendable philosophy of anti-dam people that we ought not to screw around with Mother Nature on the moral and ethical principle that this is not OUR planet to fiddle with. Fair enough. But opponents of dams and reservoirs should state their rationale simply and clearly instead of trying to dress it up in arguments that rest on dubious or even contradictory reasoning.
scientific earthling
Reply | Report Abuse | Link to thisMy opinions "may" be related to the fact that I "know" hydroelectric power, just as your opinions may be related to the fact that you "know" chemistry. This knowledge is not a "biased" knowledge. Knowledge is neutral. It's how you use the knowledge that determines if you are biased or not.
I know, from my experience with hydro plants, that hydro power is a renewable source of energy, emission free, and has very many "good" sites that do not require large reservoirs. That being said, there are a few hydro sites that should not have been developed. Like any energy production source, hydro sites have trade-offs that must be considered.
I would never support hydro power "blindly", but I do support hydro power because it is an excellent source of electrical power. The dams also have the ancillary benefit of providing irrigation water for farmers, drinking water for municipalities, and flood control to save lives. Not many other "renewable" energy sources have these benefits.
The source you reference on methane is, indeed, a "biased" source because it uses it's knowledge only in a manner that promotes it's agenda. It does not explain that its methods of measuring methane in large reservoirs is not an accepted standard (because no accepted standard exists), and uses erroneous assumptions to arrive at its conclusions.
Furthermore, you cannot refute the information that I quoted from the Goddard Space Institute concerning the fact that wetlands, rice paddies, and coal/gas mining are the major emitters of methane.
In conclusion, what's your point on methane emissions for reservoirs, scientific earthling. If the oceans only emit 3% of the world's methane, how large a hydro reservoir would you need to produce even a 0.1% methane emission? And considering that there are presently no "established" standards for measuring methane emissions from a large reservoir (confirmed by the present studies being conducted by Ontario Hydro & Quebec Hydro with the Canadian Fisheries) how did the internationalrivers.org arrive at their values.
David M. Clement.
Reply | Report Abuse | Link to thisHydro electricity is a renewable source of energy, for years I believed it was the best source of energy in the world. Now I am sceptical of every technology. When we trade-off do we know what we are trading off?
When it comes to irrigation, are you aware that in Australia irrigation has led to desertification. The Murrey is beyond repair, we shall not be producing the rice, wheat and other crops that have fed the world for so long. Please read Peter Andrews - Beyond the Brink to know what caused the desperate condition of our farmers. He has actually restored salty depleted lands, his methods will astound you.
Perhaps my source of methane info is biased, but they all are, everybody is pushing an agenda. My agenda is to delay the extinction of homo sapien, he has been around for such a short time, dinosaurs and other creatures existed for millions of years.
Methane is just one of several naturally occurring gasses that shape our climate, I have no special concern with it, without it live would not exist. I am concerned by balance. I am concerned that we have wiped out 25% of the vegetative cover of our planet, I am concerned that this reduces 25% of the basic food generated on our planet. I am concerned that energy used to create food is now heating the planet. I am concerned that the temperature range dampening effect & rain inducing effect of forests is being destroyed.
Most of all I am concerned by a loss of biodiversity, absolutely necessary for the survival of our species. I am aware that the earth will heal after our extinction, but it will not be the same without life forms that appreciate its genius.
There has been no mention yet of the lives lost when dams burst or cause Earthquakes, these vastly exceed the number caused by coal burning, oil, or nuclear power generation.
Reply | Report Abuse | Link to this@drfrank
Reply | Report Abuse | Link to thisSo many things are wrong with nuclear power.
* The amount of water needed to cool down the tanks
* No where to safely put the radioactive waste.
* Huge overturn costs
There are so many more..
http://www.sciam.com/article.cfm?id=can-nuclear-power-compete
I do think that it is possible to make hydro sustainable. I think it's a great idea to use already existing dams and converting them to be used as an energy resource.
BUT
There have been many problems with hydro in the past. I live in Canada and there has been many problems with hydro Quebec. The James bay project in particular caused certain problems; they flooded a giant area and it disturbed many species. As for the huge three gorges dam in china that goes across the Yangtze river also caused problems for the same reason. They flooded a huge space. Many people rendered homeless, some animals became endangered, and the Yangtze river dolphin is now consequently extinct. These dams block access to migratory fish.
http://www.spiked-online.com/index.php?/site/article/3709/
My thoughts: I think hydro has a great potential but flooding massive areas is not sustainable at all. Harnessing the power of moving water is great, we just need to be careful with how we do it. Wave seems like a more promising concept to me.
I also think that we need to look at all these projects individually. We can't box hydro as good or bad. In some places hydro will work with out having negative side effects. Other ecosystems would not be able to sustain a hydro dam.
@ syhprum
you bring up a good point about dams having the potential of having disastrous effects.
Dams should be built with "what if it breaks" in mind. As should everything.
There seems too many dams in China, which do impair our ecosystem. Someones also claim dams create as much CO2 as mine.
Reply | Report Abuse | Link to thisBack from vacation.
Reply | Report Abuse | Link to thisMy main point was that Hydroelectric power is not 100% emission free. There have been many articles on the issue. You are correct that there are no acceptable standards, however that does not dismiss the hazards.
Whether you argue about the exact amount of CO2 produced is irrelevant, it exists. It is an increase in methane output in areas where organic matter is flooded and carbon sinks are eliminated (forrests, etc...). I don't care whether all of the current and future dams add up to only .01% of what the oceans produce, it is an increase. Perhaps the earth is only able to handle what the oceans produce... this tiny amount produced by dams may be the tipping point.
Please, don't scoff at this concept. Nobody knows the answer. Not you. Not me. And the concerns of many people hinges exactly on this issue. Are we exceeding the limits of what the earth can support.
So... Any future hydroelectric power dams must be built more carefully. I am not even sure that big dams need to be built. Big dams are built on the assumption that bigger is better. What about smaller step dams that don't produce flooding?
A Hoover-type dam could be replaced by one hundred smaller dams that use newer, more efficient technology. If one or more fail, reserve capacity in other dams could make up for losses and maintenance. Drops of 5 to 10 feet might be enough to produce sufficient potential to run newer turbines. They could allow a river or stream to maintain its ecosystem. Salmon are capable of jumping the distance.
Think smaller, not bigger.
No one has addressed the issues with in-river systems... They are testing some newer units in the East River in New York City. We are anxious to learn the results.
Hydro power has a huge negative impact. Many of the best rivers and valleys are flooded and lost forever. It is much the same as mountain top removal method of coal mining. Both produce cheap energy for us right now but all future generations, for thousands of years will pay for our cheap energy. We destroyed much of the Grand Canyon so that a few hundred people in the 1930's could have temporary dam building jobs.
Reply | Report Abuse | Link to thisNot always nes. to build big dams to generate power. In many cases tunnels may do the job. And there surely is a big potential in alredy existing dams.
Reply | Report Abuse | Link to thisJon Ottar
Reply | Report Abuse | Link to thisHe was talking mostly about existing dams and run of river generators. It's this last kind that has great potential both for rivers and tidal with minimal impacts. While they have been having problem with them, it's because the engineers don't understand the underwater environment. I've done them for 30 yrs without a problem but I live on the water so understand it well.
Nor is marine fouling a problem as it's well understood. Mostly they just don't understand the huge torque involved.
Wave power is tiny and only viable where waves are regularly 6' and higher. Not many places match that and even then produce little. Vs the river/tidal resources which are vast, enough to power at least 1/4 of the US.
Nor is the methane a big deal as it's not big and quickly changes into CO2. A much bigger deal is the tundra melting releasing megatons of methane and CO2 if we don't use hydro.
There are place to use dams and places not to but river/tidal units can let many be removed without losing power, in fact increase it. But as the glaciers melt away no longer soring water we'll need more dams in the mountains to catch the sown/rain to replace them or many places are going to be screwed.
Hydropower is a very good way of generating one of our energy needs, but we are always looking at the bigger picture, where we have to block off a major river,
Reply | Report Abuse | Link to thisMany smaller systems would be much better at getting what we need, a larger number of smaller turbines would be admittedly slightly more expensive to put into place, but would give a much more stable entity if ever there were any major dissasters, if a small number of the smaller units were off line for repair or damage we would still have a supply with which to work with, take out a large system and we would be without vital power, especially if there was any fuel rationing
where one would benefit like hospitals and many others would go without, not good in a colder winter for the elderly who reley on electricity.
Locally our river used to have 15 mills in only a mile and a half stretch, the water way was not obstructed and the water was used many times along its path which was always open for fish, eels etc to migrate.
A huge system has some definate drawbacks, it would eventually silt up, needing a full drain out and shut down for servicing, lke a system in Italy which is drained and cleared every 12 years.
The Hoover dam is already well under parr because of silting and many others will suffer the same, there life expectancy is relatively short like that of nuclear, wind is a load of hot air and some of the most expensive ornaments once the wind stops blowing, rivers are a much better optionbut many, not the few,
Major entities would also be more open to terrorist attacks.
I forgot to say that smaller units would not require huge areas of land to be evacuated, this alone can cost more than the whole, and nature would still be allowed to flourish,
Reply | Report Abuse | Link to thisCheck out a story I found about a local valley where in the Uk in the 30's a most beatifull valley was destrioyed for a water system which doesn't even have a hydro system fitted, what a waste
www.mardal.green.talktalk.net
Hydro-poqwer generation can be done on a larger scale in USA by utilising as many dams out of the 80,000 existing dams .In fact like in Tasmania of Australia,more hydro-power generation can be done by taking up cloud seeding operations to augment both annual snowfall and rainfall by 10% to 205 depending upon the meterological,geographical and topographical features of the region For more details on cloud seeding see the following web sites and their links;
Reply | Report Abuse | Link to thishttp://tshivajirao.blogspot.com/2010/09/cloud-seeding-simplified.html
http://tshivajirao.blogspot.com/2008/02/weather-modification-cloud-seeding-is.html
http://www.gitam.edu/cos/env/English-Book-FirstPages.pdf
http://www.varunyantra.org/faq.html
http://jcsepa.mri-jma.go.jp/outreach/20070131/Presentations/P3_Yao.pdf
http://www.abc.net.au/catalyst/stories/2714955.htm
prof.T.ShivajiRao,M.S.Rice,Houston.1962]Ph.D[Hony]
Expert on cloud seeding project,Government of A.P.state,Hyderabad.India[2004 -2009]
Whats this - a paid ad for hydropower lobby ?!
Reply | Report Abuse | Link to thisI see many of you left comments complimenting author and article (like JamesDavis), but what you missed is the fact that author of this article is Linda Church Ciocci, Executive Director, National Hydropower Association !!!
I will bet my life on same tale from assumed, for argument sake, "ex.dir. of national coal & oil association" for example, if given chance and if such association exist....