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kristopher

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Member since: Fri Dec 19, 2003, 02:20 AM
Number of posts: 29,253

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A marriage made in sunlight: Invention merges solar with liquid battery

A marriage made in sunlight: Invention merges solar with liquid battery
September 22, 2016 by David Tenenbaum


This solar-charged battery, developed in the lab of Song Jin at the University of Wisconsin–Madison, directly stores energy from sunlight in a tank. Credit: David Tenenbaum


As solar cells produce a greater proportion of total electric power, a fundamental limitation remains: the dark of night when solar cells go to sleep. Lithium-ion batteries, the commonplace batteries used in everything from hybrid vehicles to laptop computers, are too expensive a solution to use on something as massive as the electric grid.

Song Jin, a professor of chemistry at the University of Wisconsin-Madison, has a better idea: integrating the solar cell with a large-capacity battery. He and his colleagues have made a single device that eliminates the usual intermediate step of making electricity and, instead, transfers the energy directly to the battery's electrolyte.

Jin chose a "redox flow battery," or RFB, which stores energy in a tank of liquid electrolyte.

In a report now online in Angewandte Chemie International Edition, Jin, graduate student Wenjie Li, and colleagues at the King Abdullah University of Science and Technology in Saudi Arabia have demonstrated a single device that converts light energy into chemical energy by directly charging the liquid electrolyte.

Discharging the battery to power...



Read more at: http://phys.org/news/2016-09-marriage-sunlight-merges-solar-liquid.html#jCp

We Could Power The Entire World By Harnessing Solar Energy From 1% Of The Sahara

SEP 22, 2016 @ 12:32 PM
We Could Power The Entire World By Harnessing Solar Energy From 1% Of The Sahara

Could the world feasibly switch to all-nuclear power generation? If so, would that be a good counter to global warming?originally appeared on Quora: the knowledge sharing network where compelling questions are answered by people with unique insights.

Answer by Mehran Moalem, PhD, UC Berkeley, Professor, Expert on Nuclear Materials and Nuclear Fuel Cycle, on Quora:

I have taught courses in Nuclear Engineering and a few seminar courses in alternative energies. I also worked for two years starting up six solar factories around the globe. In spite of my personal like for nuclear engineering, I have to admit it is hard to argue for it. Here is the simplified math behind it.

The total world energy usage (coal+oil+hydroelectric+nuclear+renewable) in 2015 was 13,000 Million Ton Oil Equivalent (13,000 MTOE) – see World Energy Consumption & Stats. This translates to 17.3 Terawatts continuous power during the year.

Now, if we cover an area of the Earth 335 kilometers by 335 kilometers with solar panels, even with moderate efficiencies achievable easily today, it will provide more than 17,4 TW power. This area is 43,000 square miles. The Great Saharan Desert in Africa is 3.6 million square miles and is prime for solar power (more than twelve hours per day). That means 1.2% of the Sahara desert is sufficient to cover all of the energy needs of the world in solar energy. There is no way coal, oil, wind, geothermal or nuclear can compete with this. The cost of the project will be about five trillion dollars, one time cost at today’s prices without any economy of scale savings. That is less than the bail out cost of banks by Obama in the last recession. Easier to imagine the cost is 1/4 of US national debt, and equal to 10% of world one year GDP. So this cost is rather small compared to other spending in the world. There is no future in other energy forms. In twenty to thirty years solar will replace everything. There will still be need for liquid fuels but likely it will be hydrogen produced by the electrolysis of water and that powered by solar. Then tankers and pipelines will haul that hydrogen around the world. One can also envision zirconium or titanium batteries that store large quantities of hydrogen.

By the way, note that the cost of a 1 GWe (Gigawatt electric) nuclear plant is about three billion dollars. the cost of 17.3 TW nuclear power will be fifty-two trillion dollars or ten times that of solar even if all the other issues with safety and uranium supply are resolved.

All that said, there is a niche application for nuclear power....
http://www.forbes.com/sites/quora/2016/09/22/we-could-power-the-entire-world-by-harnessing-solar-energy-from-1-of-the-sahara/#34d60b553e5b

Not a deep analysis, but an interesting recitation of a widely held conceptualization of how the transition might proceed. The problems aren't insurmountable, but I'd expect such a centralized model would have (too) high distribution costs and be too subject to disruption as an outcome of normal cussed human in-fighting.

Ohio utilities' attempt to guarantee income for coal and nuclear are part of a trend

Coal and nuclear, nuclear and coal: two sides of the same centralized generation coin

Report: ‘Around market’ moves by Ohio utilities are part of larger trend

Efforts by Ohio utilities to guarantee income for affiliated coal and nuclear operations are part of a broader trend, according to a new report by legal analysts.

Starting in 2014, FirstEnergy, American Electric Power (AEP) and other companies sought to impose added fees on all customers of their Ohio utilities, in order to guarantee sales for certain power plants owned by affiliates of those companies. After federal regulators said they would require strict scrutiny of any power purchase agreements under those plans, FirstEnergy and AEP changed their proposals.

Both companies also announced an interest in seeking re-regulation of electricity generation in Ohio. If successful, that effort would reverse a 1999 law that gave customers the right to choose their own electricity generation supplier. That law also forbade utilities from favoring their own generation affiliates.

The Ohio companies’ actions are among the more aggressive “around market” efforts in a nationwide trend noted by report authors Raymond Gifford and Matthew Larson of Wilkinson Barker Knauer in Denver, Colorado. Those efforts coincide with the exit of multiple coal and nuclear plants from the market.

“This has gone from somewhere simmering on the back burner to a very broad trend,” ...

http://midwestenergynews.com/2016/09/14/report-around-market-moves-by-ohio-utilities-are-part-of-larger-trend/

Industry study: Microgrids to become ‘fundamental building block’

Industry study: Microgrids to become ‘fundamental building block’

WRITTEN BY
David J. Unger
10 hours ago



PHOTO BY Sandia National Laboratories


...Used primarily to ensure reliability and access in military and other critical applications, microgrids have emerged in recent years as a niche interest for utilities and communities looking to bring more renewables online and increase resilience in the face of extreme weather. Despite the heightened profile, microgrids – islandable networks of generation and distribution – remain a small part of the U.S. energy system, making up a fraction of a percent of the nation’s total power generating capacity.

That is poised to change, according to a report released earlier this month by the National Electrical Manufacturing Association (NEMA), an industry group representing electrical, medical imaging, and radiation therapy manufacturers.

“ moving away from a passive to an active grid,” said Steve Griffith, an industry director at NEMA. “You can actually have distributed generation based on renewable resources – solar, wind and electrical storage devices – power that not only flows from the utility to the customer, but now from the customer back to the utility.”

Microgrids help manage these reverse power flows by addressing the technical challenges of variation in voltage and frequency. It’s why NEMA envisions a future where microgrids play a foundational role in the way the broader power system operates, working in tandem with the existing power structure.

“From 2025 onwards, fully controllable, independent microgrids interconnected with links will allow for full decoupling from the alternating current (AC) electric power system.” the report concludes. “They will also facilitate the segmentation of the distribution system, a new paradigm for electric grid management.”...
http://midwestenergynews.com/2016/09/21/industry-study-microgrids-to-become-fundamental-building-block/

If interested, you can find your way to the study through NEMA's press release. Enrolling is required to download.:
http://www.nema.org/news/Pages/Electrical-Manufacturers-Say-Microgrids-Essential-to-Americas-Future-Infrastructure.aspx

"Chances are, you haven't heard of Proterra"

The 'Tesla of buses' just made a big move to eliminate diesel buses forever
Danielle Muoio

Sep. 12, 2016, 5:24 PM


Chances are, you haven't heard of Proterra.

The Silicon Valley-based start-up has one focus: to eliminate the need for a diesel bus, forever. It's something the company has been working quietly on since 2004, and has made moderate progress since. It sold its first three, all-electric buses in 2009, ramping up sales marginally throughout the years since.

Proterra started hitting its stride a bit in 2015 when it sold 62 buses across 12 different transit agencies. But with a nominal range of 146 miles, a mark below many electric cars, widespread adoption hasn't been feasible.

<snip>

The new bus body is made of a carbon fiber composite, allowing it to remain lightweight, but durable. Proterra, which makes its own batteries in its Silicon Valley office, improved energy storage and put most of the batteries "underneath the body of the bus so it helps us keep it very, very low center of gravity," Horton explained.

That innovation has resulted in a bus that fits 77 passengers and can pack 660 kWh of energy to drive 350 miles on a single charge. On a closed track, which doesn't mimick the difficulty of urban driving, a Proterra bus with just a 440 kWh battery achieved 600 miles on a single charge...

More at: http://www.businessinsider.com/proterra-unveils-electric-bus-with-350-mile-range-2016-9?r=UK&IR=T


Energy secretary: Administration working hard for coal power

Energy secretary: Administration working hard for coal power

Jonathan Mattise, Associated Press Updated 2:31 pm, Monday, September 12, 2016

MORGANTOWN, W.Va. (AP) — President Barack Obama's energy secretary said Monday that the administration isn't waging a "war on coal" and is working to maintain coal as an important part of a low-carbon energy future.

At the Mid-Atlantic Region Energy Innovation Forum at West Virginia University, U.S. Energy Secretary Ernest Moniz said Congress needs to pass tax credits that could help power plants burn coal more cleanly. The credits would send a signal to utilities and investors about coal's viability for future power plant investments, Moniz said.

Especially in southern West Virginia, mines are continuing to close and miners keep losing good-paying jobs, with few other employment options available. The administration is infusing money into communities where the coal industry has withered to develop different economic opportunities, Moniz said.

"Plain and simple, 'War on Coal' is not what this administration has as a policy or has done," Moniz told The Associated Press. "It starts with — make no bones about it — we and the world are heading to a low-carbon future."...
http://www.sfgate.com/news/article/Energy-secretary-Administration-working-hard-for-9217711.php

As Japan's sodium cooled fast reactor decommissioning nears reality, local politicians lash out

As Monju decommissioning nears reality, Fukui politicians lash out
BY ERIC JOHNSTON
SEP 15, 2016

OSAKA – News that the central government is finalizing plans to decommission the Monju fast-breeder reactor in Fukui Prefecture has sparked anger and fear among local politicians about what will happen to their economy, and could make Fukui’s cooperation in restarting other reactors more complicated.

In Tsuruga, where Monju is located, Mayor Takanobu Fuchikami said last week that decommissioning would hugely impact the local economy. Tsuruga receives government subsidies for hosting the plant and has a service industry that derives much of its income from officials, engineers, and others who visit the facility.

...

The Japan Atomic Energy Agency, which manages Monju, estimates decommissioning will cost more than ¥300 billion and take 30 years to complete. Currently, it costs about ¥20 billion a year to maintain the idled plant.

Additional costs, which are unknown, include the cost of shipping Monju’s spent fuel and radioactive waste to a mid-term storage facility. No such facility exists and there are no plans to build one anytime soon.
http://www.japantimes.co.jp/news/2016/09/15/national/monju-decommissioning-nears-reality-fukui-politicians-lash/#.V9w70jth2Rs



From The Asahi Shimbun
EDITORIAL: Monju has run its course and should now be scrapped
September 15, 2016 at 14:55 JST

The government is assessing what to do about the Monju prototype fast-breeder nuclear reactor, with one option being to decommission the trouble-prone facility.

It should decide swiftly to scrap the experimental reactor in Tsuruga, Fukui Prefecture.

Monju has remained mostly idle for the past two decades or so. Restarting it would be hugely expensive. Putting the necessary safety measures in place would require an outlay of hundreds of billions of yen. The obvious solution is staring the government in the face.

Monju was designed to underpin a nuclear fuel recycling program in which plutonium extracted from reprocessed spent nuclear fuel is burned in a fast-breeder reactor. The ability to generate more fissile material than is consumed was regarded as “dream” technology.

But Monju has been mostly offline since a sodium coolant leak accident in 1995.

In 2012, it was revealed that safety maintenance checks had missed about 10,000 pieces of equipment. In response, the Nuclear Regulation Authority halted preparations to bring the reactor back online. It urged the science and technology minister last November to find a new operator for the reactor in place of the government-backed Japan Atomic Energy Agency.

The science and technology ministry...
http://www.asahi.com/ajw/articles/AJ201609150039.html




Accident at the Monju fast breeder reactor
SEPTEMBER 3, 2010
The Japanese Atomic Energy Agency (JAEA) disclosed details of an accident that happened on August 26, 2010 at the Monju fast breeder reactor (here is the original JAEA letter). As described in the press, the accident involved a 3-tonne "fuel-replacement device" falling into the reactor vessel when being removed after a scheduled fuel replacement operation. According to JAEA, the accident may result in a delay in bringing the reactor back into operation, since the device may have damaged the reactor vessel wall.

The Monju reactor was restarted on May 6, 2010, after a 15-year shutdown that followed a major sodium leak and fire. As IPFM reported at the time, the decision to restart the reactor was quite controversial, with citizen groups and newspapers opposing the move.
http://fissilematerials.org/blog/2010/09/accident_at_the_monju_fas.html


For a background of Japan's breeder program, see the IPFM report Fast Breeder Reactor Programs: History and Status.
http://fissilematerials.org/library/rr08.pdf

Japanese steel in French nuclear facilities found to have high impurity level

Japanese steel in French nuclear facilities found to have high impurity level
KYODO
SEP 14, 2016

Steel supplied by Kitakyushu manufacturer Japan Casting & Forging Corp. to nuclear facilities in France has been named in an investigation that found it had a high level of impurity, the nuclear watchdog said.

The Nuclear Regulation Authority said the standard for carbon content in metals — a gauge of impurity — is below 0.22 percent in France, while the figure is below 0.25 percent in Japan.

But in some products provided by Japan Casting & Forging Corp. for some nuclear facilities, carbon content in steel was over 0.3 percent.

The NRA said it had recently been briefed by French regulators and needed to carry out its own tests to determine the quality of the steel.

The higher the concentration of impurity in steel, the weaker the product....


http://www.japantimes.co.jp/news/2016/09/14/national/japanese-steel-french-nuclear-facilities-found-high-impurity-level/#.V9r_uDth2Rt


I'm sure they'll find that the original design specs were really nothing more than a suggestion, merely a bit of whimsical thought that flitted through the daydreams of the original designers...

ionizing radiation generates distinctive mutational signatures

Abstract
Ionizing radiation is a potent carcinogen, inducing cancer through DNA damage. The signatures of mutations arising in human tissues following in vivo exposure to ionizing radiation have not been documented. Here, we searched for signatures of ionizing radiation in 12 radiation-associated second malignancies of different tumour types. Two signatures of somatic mutation characterize ionizing radiation exposure irrespective of tumour type. Compared with 319 radiation-naive tumours, radiation-associated tumours carry a median extra 201 deletions genome-wide, sized 1–100 base pairs often with microhomology at the junction. Unlike deletions of radiation-naive tumours, these show no variation in density across the genome or correlation with sequence context, replication timing or chromatin structure. Furthermore, we observe a significant increase in balanced inversions in radiation-associated tumours. Both small deletions and inversions generate driver mutations. Thus, ionizing radiation generates distinctive mutational signatures that explain its carcinogenic potential.


Mutational signatures of ionizing radiation in second malignancies
Sam Behjati, Gunes GundemPeter J. Campbell
Nature Communications 7, Article number: 12605 (2016)
doi:10.1038/ncomms12605
Open Access http://www.nature.com/articles/ncomms12605

Discussion
Overall we identified two genomic imprints of ionizing radiation, an excess of deletions and of an exceedingly rare type of rearrangement, balanced inversions. The validity of our study may be limited by the overall number of tumours we examined and the small number of each tumour type. Yet it would seem unlikely that the enrichment in radiation-associated tumours of deletions and of balanced inversions occurred by chance. This view is supported by our statistical analyses as well as the fact that the signatures were tumour-type independent. Both signatures were present across four different tumour types and could be validated in a cohort of radiation-exposed prostate cancer lesions, despite differences in the biological context of radiation-exposed prostate tumours and radiation-associated second malignancies (Supplementary Note 2). Particularly striking is patient PD11331 whose primary prostate lesion was irradiated after metastases had formed. The primary lesion, but not the metastases, exhibited the genomic features of ionizing radiation.

The relatively low number of mutations that we directly linked to ionizing radiation may seem surprising for such a well-known carcinogen. It is certainly considerably less than seen for cancers associated with tobacco, sunlight or aristolochic acid exposure10. This probably reflects the fact that although the attributable risk of such cancers is high, the absolute risk is relatively low. For example, >90% of angiosarcomas occurring after radiotherapy for primary breast cancer are attributable to radiation, but only one in a thousand women receiving such radiotherapy will develop angiosarcomas37, with a latency of many years. This suggests that although ionizing radiation clearly pushes bystander cells in the radiotherapy field towards cancer, the absolute burden of radiation-induced mutations per cell would not be high and additional driver mutations would be required.

ionizing radiation generates distinctive mutational signatures

Abstract
Ionizing radiation is a potent carcinogen, inducing cancer through DNA damage. The signatures of mutations arising in human tissues following in vivo exposure to ionizing radiation have not been documented. Here, we searched for signatures of ionizing radiation in 12 radiation-associated second malignancies of different tumour types. Two signatures of somatic mutation characterize ionizing radiation exposure irrespective of tumour type. Compared with 319 radiation-naive tumours, radiation-associated tumours carry a median extra 201 deletions genome-wide, sized 1–100 base pairs often with microhomology at the junction. Unlike deletions of radiation-naive tumours, these show no variation in density across the genome or correlation with sequence context, replication timing or chromatin structure. Furthermore, we observe a significant increase in balanced inversions in radiation-associated tumours. Both small deletions and inversions generate driver mutations. Thus, ionizing radiation generates distinctive mutational signatures that explain its carcinogenic potential.


Mutational signatures of ionizing radiation in second malignancies
Sam Behjati, Gunes GundemPeter J. Campbell
Nature Communications 7, Article number: 12605 (2016)
doi:10.1038/ncomms12605
Open Access http://www.nature.com/articles/ncomms12605

Discussion
Overall we identified two genomic imprints of ionizing radiation, an excess of deletions and of an exceedingly rare type of rearrangement, balanced inversions. The validity of our study may be limited by the overall number of tumours we examined and the small number of each tumour type. Yet it would seem unlikely that the enrichment in radiation-associated tumours of deletions and of balanced inversions occurred by chance. This view is supported by our statistical analyses as well as the fact that the signatures were tumour-type independent. Both signatures were present across four different tumour types and could be validated in a cohort of radiation-exposed prostate cancer lesions, despite differences in the biological context of radiation-exposed prostate tumours and radiation-associated second malignancies (Supplementary Note 2). Particularly striking is patient PD11331 whose primary prostate lesion was irradiated after metastases had formed. The primary lesion, but not the metastases, exhibited the genomic features of ionizing radiation.

The relatively low number of mutations that we directly linked to ionizing radiation may seem surprising for such a well-known carcinogen. It is certainly considerably less than seen for cancers associated with tobacco, sunlight or aristolochic acid exposure10. This probably reflects the fact that although the attributable risk of such cancers is high, the absolute risk is relatively low. For example, >90% of angiosarcomas occurring after radiotherapy for primary breast cancer are attributable to radiation, but only one in a thousand women receiving such radiotherapy will develop angiosarcomas37, with a latency of many years. This suggests that although ionizing radiation clearly pushes bystander cells in the radiotherapy field towards cancer, the absolute burden of radiation-induced mutations per cell would not be high and additional driver mutations would be required.


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