Dam emissions, not so bad after all

In a warming world (if it actually is), there’ll be more rain therefore Hydro will be a more viable solution in more locations than otherwise

[youtube http://www.youtube.com/watch?v=SBQ-vW6rz_Y&w=560&h=349%5D
Dam emissions!

Not in the same way or amounts suyts…

Er, what purpose does evaluating the co2 and ch4 emissions over the life of a hydroelectric project serve? Electricity output; impact on homes, wildlife and habitat of damming; connection to grid; cost per unit; they’re the main factors to consider.
Can they move on from obsessing over the carbon arseprint of cattle, etc, and get their senses back?

suyts – yes and no.
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Oh, my……are they really that ……. … Yeh!! Cause the vegetation and organic matter wouldn’t decompose if the dam wasn’t built!!
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Decomposes differently at different rates and with different byproducts. For example, a log in a forest can take 50 years to decompose and much of the decomposition is immediately tied into the growth of other organisms such as moss, fungus, etc while the reservoir lake will decompose most of the plant matter in it within 10-15 years. Also, the type of decomposition that happens in open air is different than the decomposition in water – the air-decomposed log generates a LOT less methane than the log which is submerged.
Don’t take me the wrong way – worrying about the CO2 and CH4 contribution of reservoir lakes is silly, but the scientists in this study aren’t the idiotic morons your comment suggests. There is a very distinct difference between the emissions of decomposing matter in a suddenly-created lake and the emissions of decomposing plant matter in an open forest/jungle/grassland.

Slowest rate of arctic ice melt extent 15% since 2006
http://ocean.dmi.dk/arctic/icecover.uk.php
at this rate forget it warmistas haha.
BTW it seems that 80% of polar ice is in Antarctica so NH ice is pretty insignificant anyway. Is this true?

Having trouble believing that people actually get paid money to write this c***. How much CO2 does a dam emit?? FFS. This must surely be the high water mark for hysteria about a harmless, natural, plant-fertilizing trace gas essential for all life on earth.

I have to bet the farm here that the largest volume of emitted GHG you’re going to get from a reservoir is water vapor. It wasn’t mentioned in the article, but water vapor really is in the top tier of climate affecting gases. I get the feeling sometimes that people just like to talk about CO2 rather than science.

Good grief. To even mention that CO2 or methane is a problem regarding a hydro-electric dam….. I am speechless. Must be a different planet.
Just visited the Hoover-Dam. A Great achievement for mankind. Something to be celebrated.

Cwaeth Dan Santo:

Decomposes differently at different rates and with different byproducts.

Indeed. The rapid, highly exothermic decomposition that releases massive amount of CO2 and soot on a timescale of hours or days rarely happens under water. I think we’re onto some serious science here.

dp says: August 2, 2011 at 7:41 am
I have to bet the farm here that the largest volume of emitted GHG you’re going to get from a reservoir is water vapor. It wasn’t mentioned in the article, but water vapor really is in the top tier of climate affecting gases. I get the feeling sometimes that people just like to talk about CO2 rather than science.
Can you imagine them trying to cap and tax H2O? what a riot!? (probably a double entendre)

“When rivers are dammed… flooding creates lake-like conditions”.
I always thought it actually created a lake ?

It is really silly to worry about CO2 from dams or anything else for that matter.

I’m not sure why there would be any additional methane or CO2 coming from dams since the vegetation in question would eventually die off and rot, anyway?

Mike Bromley, indeed you did. 44% of their budget comes from Federal grants! The real problem does not seem to be CO2 but a higher education system which has run out of control. A Phd can be gained by putting ones name to a pointless piece of, as you say, claptrap like this. then you have your food ticket for life. A previous posting states that tides have not always been the same! The mind boggles. Another bunch have discovered that it is dryer in Texas than it was 12 years ago! I deeply resent paying taxes to keep these morons off the street when they would actually achieve more with a broom and a wheely cart on the street than they do now with their X-box and Nintendo computer models.
. The next victims of this recession should be the “scientists” who pump out pointless research on government money. Each and every “scientist” should be made to work for a minimum of 10 years in a commercial industry before being granted a PhD, and then only if they can demonstrate a level of achievement or innovation above and beyond the norm.

vboring says:
August 2, 2011 at 8:00 am
“They seem to ignore the CO2 emissions avoided by preventing floods…”
Exactly ! Can you imagine what happened whenever the Colorado river flooded before the Hoover Dam? Lake-like conditions again, and again, and again…..Whole areas was flooded, ruining peoples lives. But who care about people…..

Any news on the Three Gorges Dam in China? Not from the the CO2 it might release, just the effect of the increasing mass of water on the ground underneath.

“the authors revealed that these systems emit 48 million metric tons of carbon annually“ (my bold)
Blimey – what is happening to all that carbon? Are we harvesting it? Is it being burned in coal power stations?
/sarc

Bystander,
Once again you make bad assumptions. Nobody here is reflexively against any form of energy. What we oppose is the subsidizing of energy forms that cannot compete on their own.
This does not apply to hydro. Therefore the only people who are reflexively against it are your fellow eco warriors.

oeman50 says:
It also matters if the flooded land for the reservoir was logged or not before it was filled. Rotting wood at the bottom of a lake can generate a lot of methane. However, most states now require saleable timber to be logged before filling, but I know of some that were filled before this became a requirement.
At least one company has developed a remote controlled mini-sub to log trees in such lakes. Since this is commercially viable it looks like wood dosn’t rot that quickly in fresh water lakes.

What am I missing here? It was my belief that trees, and thus wood, submerged in water does not break down. Kariba Dam on the Zambezi was flooded around 1957 creating Lake Kariba. There were hundreds upon hundreds of acres of trees submerged and semi-submerged. They are dead of course, but the trees themselves are still there some fifty or so years later. Couldn’t have been a lot of CO2 generated from that source. Great for the bream and tiger fish that inhabit the lake and great for those of us who have been privileged to fish there.

http://www.theglobeandmail.com/report-on-business/small-business/start/company-logs-wood-from-panama-canal/article1817698/singlepage/#articlecontent
http://www.theglobeandmail.com/report-on-business/small-business/business-categories/sustainability/african-treasure-bc-firm-harvests-submerged-forest/article2101132/

Bob Kutz asked some good questions above. I don’t see that anyone’s answered yet so I’ll take a crack at it. In reverse order:
> Can anybody explain why a reservoir would produce substantially more CO2 than a non-dammed river?
Damming the river floods much of the surrounding hillside, killing all the grasses, trees and bushes that lived there as the reservoir fills. While those plants are replaced by water-plants (algae, etc), the total biomass is much smaller, at least according to these researchers. The net loss of biomass becomes a net gain of gas when the it rots. Assuming steady-state, this is a one-time hit, I think.
> Can anybody explain the logic why hydroelectric dams produce substantially more CO2 than non-hydro?
Hydroelectric dams are designed to keep more of the water moving than non-hydro dams. While both will kill the plants on the surrounding hillsides as the reservoir fills up, the non-hydro dams have a good chance of becoming anerobic at the bottom fairly quickly. If it happens fast enough, the dead trees, etc may never rot at all. Hydroelectric dams will tend to keep the bottom water moving more, keeping the water aerobic and allowing decomposition to progress.
The movement of water also affects the temperature distribution, keeping the bottom water from getting as cold as in a more still reservoir. (See above about the reason temperature affects decomposition.)
Hope that helps.

What almost everyone forgets regarding alternative energies, including hydro, is how much carbon dioxide was poduced and btus were burned to manufacture and erect these monuments to energy stupidity.
Hydro in particular uses an enormous amount of concrete. Concrete is about 1/3 cement. Cement making accounts for about 4% of all the CO2 put into the atmosphere by man. (Man only accounts for 3.27% of all CO2 put into atmosphere.)
Does anyone know what the Energy Returned On Energy Invested (EROIE) is for hydro?

From mkelly on August 2, 2011 at 1:10 pm:

In my home town there is a hydro power plant that uses wood from an African tree for the bearings on the shafts. The wood gets harder submerged over time. (…) Wood better than steel for bearings who’d a thunk it.

http://www.plantservices.com/articles/2005/469.html

Wood bearings in the new millennium
They have been supporting rotating shafts quite successfully for thousands of years and will continue to do so in the future.
By J.R. Steurnagle, Woodex Bearing Co., Inc.,
…
When the steering sweeps on ships gave way to vertical rudder shafts, wood was the bearing material of choice. Lignum vitae, an extremely dense, tropical hardwood, was soon found to be best for this and other submerged marine applications. So dense that it will not float, “lig” has a high natural oil content, making it self-lubricating and especially resistant to deterioration in water.
When kept wet, as in most shipboard applications, lig possesses tremendous strength and wear resistance. When steam propulsion arose, lignum vitae became the bearing for propeller shafts, and it was common to see bearings last scores of years–frequently as long as the ships themselves.
Lignum vitae naturally attracted landlubbers’ interest, and it became a popular bearing material for waterwheels. Many hydro turbines today still operate on lignum vitae bearings installed fifty or more years ago, despite having received little or no maintenance since their installation.
…

There’s a pdf on the construction and use of wood bearings. The originating source:
http://practicalaction.org/docs/technical_information_service/oil_soaked_wood_bearings.pdf
Problem is it’s not downloading well for me, and what came through was reported as damaged, unreadable. I found it at this alternate site, use download link:
http://sheltercentre.org/library/oil-soaked-wood-bearings-how-make-them-and-how-they-perform
M$ Word in pdf, opened just fine.
Important warning! As found out by knifemakers using “exotic woods” for handle materials, these naturally-oily woods can be very dangerous. Search for “exotic wood dust danger” for more official info, here’s a blog thread with precautionary advice and anecdotal reports. Severe allergic reactions can be triggered by dust or even mere skin contact with the wood. IIRC people have died from exposure, come to think of it since a person can die from a single peanut I would be surprised if no one had died.
Oh, and as a “The state of California has determined” warning, the dust is carcinogenic. Apparently technically all wood dust is carcinogenic as well.

Charles S. Opalek, PE says:
August 2, 2011 at 2:34 pm
Does anyone know what the Energy Returned On Energy Invested (EROIE) is for hydro?
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Charles I don’t have it with me at the moment, but I can probably get it at work. But my thoughts are that as time passes, it surpasses any other source of electricity. The pricing certainly beats anything else. Coal and Nuke included. While it does take a great bit of energy to place a generating dam, once in place, its relatively done as far as energy invested. Sure, there’s maintenance and monitoring, but the fuel is free and is delivered to the generator with no further investment. The life expectancy of a turbine in out of this world! There’s some over 50 y/o still in use! (If we updated them, we’d prob get more generation…….)

To all the “logs don’t rot in lakes” commentors,
1) Some logs, some lakes – it depends on the type of wood and the temperature, aeration, acidity and other factors of the water.
2) Logs don’t actually matter anyway. The majority of the biomass of a tree is in its leaves, not in the trunk. (This, of course, depends on the type of tree.) And thats even before factoring in the biomass of the grass, shrub and other sunken vegetation. No matter how many unrotted logs you’ve found, it’s exceptionally rare to find a deposit of unrotted leaves or grass unless the water is very cold, still and anaerobic.

Wil says:
August 2, 2011 at 2:23 pm
Dams do not decrease the flow rate of a river once the water is held in reserve. You see, once the water is there, its a question of the people manning the dam to speak who are not doing their jobs. You can not blame a dam for low flow after the river is back to its flow-rate.
In the case of the river always “flowing at a certain rate..” Well its probably just as likely that it happens like that too at times that it is in drought and the flow-rate is reduced. Dams do not stop water from flowing, people do. When people take water out of the system as in Colorado this is something to be concerned about. When people do not take flow rate and environmental concerns such as fish into consideration, this is a concern. You can solve these problems easilly and flow-rate is never reduced by dams. Its all depended on water flowing into the system.
So as you can see…. its more about the management of the dam after the fact then anything else. But by saying dams ruin the country-side is really not looking at the big picture. They add to the country-side by creating a lake that is permanent instead of flood-plains that flood periodically and can not really be used for anything of value.

In the hydo reservoirs down the road there are entire forests of trees underwater from when they built the dams, one in 1905, one in 1930. When they lowered the water to fix the dams people were shocked that they were water skiing above a forest of trees only 3-5′ below the surface. Many had to be knocked down for safety reasons.
As far as AGW, I would theorize that the dam would be a net positive. The waterfalls used to put up a tremendous water vapor. Now the river slowly boils out water at the base of the dam. Likewise while there isn’t a forest or grasslands under the water any more, there is a whole biosphere of plant life that probably represents far more flora than the earlier forests did. It also provides clean energy.
The biggest CO2 producer for the dams probably be tourism as people boat, fish, swim, and catch a sunset. Next would be the licensing process that took 8 years and a 40,000 page document plus supporting studies.
The hydo projects don’t leave the rivers dry as happens some places, they are ‘Run of River’, what goes in goes out and water levels in the reservoir are maintained within inches, unless they fall below minimum flow to support the river downstream.

Viv Evans says:
“the authors revealed that these systems emit 48 million metric tons of carbon annually“ (my bold)
Blimey – what is happening to all that carbon? Are we harvesting it? Is it being burned in coal power stations?
It dosn’t help that these kind of people frequently say “carbon” when they actually mean “carbon dixoide” so they may actually mean 12Tg.

Finally! We finally have something we can use! Thank you Lord! Oh, thank you!… wait a minute… uhoooh… that means the Warmistas will want to build Arks, well at least one, and seed the atmosphere, and they probably wont let two Coolists on board… WE’RE DOOMED!!!! We just can’t win. Oh well, what’s on TV Martha?

On second inspection, however, the paper seems to indicate that they are concerned with ongoing emissions from hydro-electric. I can see the one time effect of converting a certain terrestrial biomass to an aquatic state and lowering the overall amount of CO2 sequestered (in trees for example), but the amount of CO2 and methane actually generated by the hydro-plant’s ongoing operation should be near nil, except for the before mentioned maintenance requirements.
Still not sure why this has any validity whatsoever.
Let’s say you could instantly convert a free flowing river to a hydo-capable impoundment with a mature biomass; the difference in CO2 content from state 1 to state 2 would be the only difference, as the hydro dam doesn’t actually produce CO2 or methane in it’s operation.
“Through an analysis of 85 globally-distributed hydroelectric reservoirs, the authors revealed that these systems emit 48 million metric tons of carbon annually, a downgrade from earlier estimates of 321 million metric tons. Further putting things in perspective, hydroelectric reservoirs are responsible for less than 16% of the total carbon dioxide and methane emissions from all types of human-made reservoirs combined.”
Now I don’t get where either the 48 or 321 metric tons comes from, once the existing vegetation becomes flooded and releases its CO2. That should be the end of it; beginning state minus end state equals total amount of emmission, not an annual figure, but a total figure divided over a period of one or two years and then done.
Their paper still doesn’t make much sense. Once the landscape is changed the CO2 state should remain at equilibrium, producing no additional CO2, hydro or not.

Obviously, we’re damned if we do and damned if we don’t, so the only thing that’s going to make the environmentalists happy is for us plebes to kindly report to the suicide booths. Our remains can go to make soylent green.

The sahara loses more heat at night than it gains during the day – the only reason it stays warm is wind. Why do deserts lose so much heat at night – simple, lack of water – the GHG that accounts for 99% of all warming

Perhaps reading the following post, “Carbon sequestration through hydroelectric generation: A variable never considered.” show first ever written about the problem. But there’s only one problem, it is written in Portuguese (but now with the Google translation !)

I believe the following paper is of relevance:
http://www.un.org/esa/sustdev/sdissues/energy/op/hydro_tremblaypaper.pdf
Highlights:
Temperate and boreal hydroelectric reservoirs produce far below the average of traditional thermal alternatives (8% max, Full Energy Chain, in gCO2 equiv./ kWh(e).h).
Dams in tropical regions vary significantly, from 1% to 200% of traditional thermal alternatives.
Much of the average emissions come from the initial decay of organic matter; It is expect that emissions will decline over time.
Hydro-electric generation is on average comparable in total average emissions with other renewables in tropical regions; There exists however a considerable variance. In temperate and boreal regions however, hydro-electric generation is by far the lowest in total average emissions /kwh )
Interesting that Nuclear also fares favorably compared to renewables (probably due to manufacturing processes).