Environment & Energy
Related: About this forumRecast Russian warheads have prevented an .4PPM global rise in CO2
Last edited Fri Aug 30, 2013, 08:27 PM - Edit history (1)
and singlehandedly turned the climate change clock back by 2 months.Russia completes Megatons to Megawatts work
"In 1993, the US and Russian governments signed an agreement for the purchase over a 20-year period of 500 tonnes of Russian 'surplus' high-enriched uranium (HEU) from nuclear disarmament and military stockpiles. These were to be bought by the USA for use as fuel in civil nuclear reactors. Under the deal, the USA transferred to Russia a similar quantity of natural uranium to that used to downblend the HEU.
The plant in Zelenogorsk in Russia's Krasnoyarsk Region was one of four enrichment plants contracted by Tenex to downblend the HEU. It has processed about one-third of the total HEU downblended under a contract signed with Tenex in 1996. ECP has also undertaken the re-enrichment of tails for the downblending, using about half of its capacity.
Known as the HEU Agreement, and sometimes referred to as the 'Megatons to Megawatts' program, it was implemented through a 1994 contract between the US Enrichment Corporation and Techsnabexport (Tenex), which acted as executive agents for the US and Russian governments. After the HEU Agreement was signed the US Enrichment Corporation was later privatized, becoming USEC Inc. Since 2000 the program has been under the US National Nuclear Security Administration (NNSA).
Since the agreement was signed, 500 tonnes of Russian weapons-grade HEU - equivalent to 20,000 warheads - have now been downblended into 15,259 tonnes of LEU."
http://www.world-nuclear-news.org/ENF-Russia_completes_Megatons_to_Megawatts_work-2908134.html
kristopher
(29,798 posts)And renewables provide 16.7% of global final energy consumption, how many years has renewable energy's contribution "rolled back the clock"?
Forgot to point out how odd this post is in light of the fact that of the 4 problems that the very pronuclear power MIT identified with adding more nuclear one of the most problematic is the way the spread of civilian nuclear power adds to the problem of nuclear weapons proliferation. The other 3 problems, of course, were high and increasing cost, safety (Fukushima anyone?) and the lack of a way to effectively waste with nuclear waste.
muriel_volestrangler
(101,154 posts)and 'singlehandedly turned the climate change clock back by 4 years'?
I would guess you've based this on the assumption that mined uranium will run out at some time in the future, and that the full amount of LEU from the warheads will then be used. But 'have prevented' and 'turned' would, even then, be pushing it - 'will possibly have', perhaps?
wtmusic
(39,166 posts)About half of U.S. nuclear energy is generated from converted Russian warheads. It's cheaper than mining it, so there's no reason not to use it.
An amount of coal which is energy-equivalent to 15,259 tonnes of LEU would create 130 gigatons (billion short tons) of CO2; each 15 gigatons of atmospheric CO2 is responsible for another PPM; each year PPMs have been going up ~2.1.
Would it all be replaced by coal? No, but it's back of napkin so I underestimated other things. If anyone wants to quibble they will probably find the carbon savings to work out higher.
muriel_volestrangler
(101,154 posts)It didn't increase the capacity of the nuclear power stations.
However, I wonder where your figure of "an amount of coal which is energy-equivalent to 15,259 tonnes of LEU would create 130 gigatons (billion short tons) of CO2" comes from.
http://world-nuclear.org/info/Nuclear-Fuel-Cycle/Uranium-Resources/Military-Warheads-as-a-Source-of-Nuclear-Fuel/#.UiESt22tyBo
http://world-nuclear.org/info/Current-and-Future-Generation/World-Energy-Needs-and-Nuclear-Power/#.UiEUEG2tyBo
So, when it's all been used, it's equivalent to about 22% of world annual electricity production. If all the world's electricity was produced with coal, the yearly emissions would be 21Gt. So we're looking at something under 5 gigatons of Co2 saved, compared with burning coal for that electricity, not 130.
wtmusic
(39,166 posts)Re: calc you are correct, I was wrong (using energy amounts for pure U-235).
To go into it another way:
Energy density U-235 83,140,000 MJ/kg
for 4% LEU: 3,325,600
for bituminous coal: 24.4 MJ/kg
Energy ratio LEU/Coal: 136295/1
Coal to equal 15,259 tonnes: 2,079,725,405 tonnes * 1.12 = 2,329,292,454 * 2.543 (factor for CO2 production) = 5.92 gigatons CO2
So about .4 PPM, at the most a few months.