Energian tuotanto, kenttägeneraattorit ja muut

ctg

Ylipäällikkö
#61
Scientists at the University of Rochester have taken a significant step forward in laser fusion research. Experiments using the OMEGA laser at the University's Laboratory of Laser Energetics (LLE) have created the conditions capable of producing a fusion yield that's five times higher than the current record laser-fusion energy yield, as long as the relative conditions produced at LLE are reproduced and scaled up at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in California.

The findings are the result of multiple experiments conducted by LLE scientists Sean Regan, Valeri Goncharov, and collaborators, whose paper was published in Physical Review Letters. Arijit Bose, a doctoral student in physics at Rochester working with Riccardo Betti, a professor of engineering and physics, interpreted those findings in a paper published as Rapid Communications in the journal Physical Review E (R).
http://www.spacedaily.com/reports/A_first_for_direct_drive_fusion_999.html
 

SJ

Ylipäällikkö
Lahjoittaja
#62
Tämähän kävisi hyvin myös koteihin pitkien sähkökatkojen varalle. Toimiskohan perus takassa niin että tuottais vielä lämpöäkin?
Kävi tuo minullakin mielessä. Itseasiassa taisin joskus tuoda esille ajatuksen, että pitäisi olla keino, jolla muuntaa polttopuun polttamisesta tuleva lämpö sähköksi. Silloin mietin, että olisiko syytä harkita höyrykoneiden uutta tulemista, mutta kun kerran tuollainen keksintö on saatavilla, niin mitäpä turhia.
 
#63
Saksalaiset sen keksivät – tuulivoimalan energia säilöön jättimäiseen kiukaaseen
Siemens ja Hampurin teknillinen yliopisto ovat kehittäneet uutta tekniikkaa tuulivoiman varastointiin, yhtiö tiedottaa.

Ratkaisussa tuulivoiman tuottama ylijäämäenergia säilötään kivilohkareista koostuvaan lämpövarastoon – eräänlaiseen jättimäiseen kiukaaseen.

Nykyisessä testilaitoksessa kivet kuumennetaan 600 celsiusasteen lämpöisiksi. Kiviä lämmittää varastoon puhallettava kuuma ilma, jota sähkölämmittimet lämmittävät.

Kun varasto halutaan purkaa, laitetaan se puhaltamaan kuumaa ilmaa ulos. Lämpö muutetaan sähköenergiaksi höyryturbiinin avulla.

Vielä keskeneräisen testivaraston kapasiteetiksi tulee 35 megawattituntia ja nimellistehoksi 1,5 megawattia. Kiviainesta varastossa tulee olemaan 2 000 kuutiometriä.

Lopulliselle tuotteelle tavoitellaan 50 % hyötysuhdetta, testilaitoksessa tämä tulee olemaan 25 %.

Siemensin mukaan yksi tekniikan suurista hyödyistä on kustannustehokkuus – sen ottaminen käyttöön on halpaa ja nopeaa verrattuna muihin energiavarastotekniikoihin.

Yhtiön mukaan tuote on valmis markkinoille parissa vuodessa.
Hävettää suomalaisena ettei tälläistä ole tullut ajatelleeksi... Mutta onko kivi kaikkein paras materiaali varastoimaan lämpöä? Onko kivilajeilla suuria eroja tässä asiassa? Entä esim. romuteräs? Metalli kuumenisi nopeammin mutta toisaalta myös luovuttaisi lämpöä nopeammin. Onkohan kammion seinämissä mitään eristeitä? Jos sielläkin on vain ympäröivä maa-aines eristeenä... Onko mitään sellaista edullista teollista eristettä olemassa mikä kestäisi 600C lämmön? Olisiko esim. metrin paksuinen tyhjiö, hiili- tai tuhkakerros yhtään parempi eriste kuin maa-aines?
 

TBman

Ylipäällikkö
#64
Hävettää suomalaisena ettei tälläistä ole tullut ajatelleeksi... Mutta onko kivi kaikkein paras materiaali varastoimaan lämpöä? Onko kivilajeilla suuria eroja tässä asiassa? Entä esim. romuteräs? Metalli kuumenisi nopeammin mutta toisaalta myös luovuttaisi lämpöä nopeammin. Onkohan kammion seinämissä mitään eristeitä? Jos sielläkin on vain ympäröivä maa-aines eristeenä... Onko mitään sellaista edullista teollista eristettä olemassa mikä kestäisi 600C lämmön? Olisiko esim. metrin paksuinen tyhjiö, hiili- tai tuhkakerros yhtään parempi eriste kuin maa-aines?
Faasimuuntuva materiaali on paras lämpövarasti... klaupersuolaa, tms ainesta maahan kaivettuna ja sinne keruuputkisto asennettuna...
 

ctg

Ylipäällikkö
#65



Merilevällä on myös uskomaton kyky varastoida energiaa. Ja meidän tapauksessa se on helposti kerättävissä, koska merialueet on pieniä ja levää kertyy vuosittain hyvinkin paljon. Tässä tapauksessa uskon, että meillä kyky tuottaa merilevä perusteisia superkapasitaattori energiansäiliöitä varmuusvarastoiksi.


 
Viimeksi muokattu:

ctg

Ylipäällikkö
#66
While the exact cause of the recent fires experienced with Samsung’s Galaxy Note 7 smartphones have not yet been precisely determined, it appears that these incidents are in some way related to the batteries.

One known problem for both the lithium-ion (Li-ion) batteries used in today’s mobile phones as well as next-generation lithium metal batteries is that they are susceptible to the growth of finger-like deposits of lithium called dendrites inside the battery. These dendrites grow so long that they pierce the barrier between the two sides of the battery and cause a short circuit, possibly leading to a fire.

Now researchers at the University of Michigan—inspired by the potential of next-generation lithium metal batteries to store 10 times more charge than conventional Li-ion batteries—have peered into lithium metal batteries to observe the growth of dendrites. They leveraged a novel microscopy tool that enables them to watch how the lithium changes inside the battery during cycling to create conditions conducive to dendrite growth.

In research described in the journal ACS Central Science, the scientists were looking for a way to observe the extreme reactivity of liquid electrolytes and Li metal inside the battery.

While other research teams have used optical microscopy techniques, such as transmission electron microscopy (TEM), to observe these reactions inside the battery during operation, the Michigan researchers are the first to link the time evolving changes to the lithium with the corresponding changes in voltage.

Researchers now have a better understanding of how the reactions between the electrolyte and the metal electrodes affect the lithium morphology and electrochemistry during cycling.

To make these observations, the researchers turned to a microscopy technique known as operando high-resolution video capture and combined it with a numerical modeling technique to see the evolution of electrode morphology and correlate it directly to voltage.

Neil Dasgupta, University of Michigan assistant professor of mechanical engineering, believes the platform they have developed is fairly simple and can be used by researchers worldwide. "It can be reproduced in any lab with an optical microscope, simple electrochemical equipment, a machine shop and a $100 budget," he added in a press release.

You can see in the video below, Dasupta and his colleague in the research, Kevin Wood, describe the issue they are trying to tackle and how their research may help solve it.
http://spectrum.ieee.org/nanoclast/...que-reveals-how-batterykilling-dendrites-grow

 

ctg

Ylipäällikkö
#67
As the electric grid is increasingly powered by renewables, it will need energy storage for when the wind isn’t blowing and the sun isn’t shining. But the three top grid-scale energy storage technologies today—pumped hydropower, lithium-ion batteries and “flow” batteries—arguably, aren’t up to the challenge.

The U.S. Department of Energy’s technology incubator ARPA-E (Advanced Research Projects Agency-Energy) wants to change that. It’s going long on a number of high-risk, high-reward R&D projects that might change the entire grid storage equation. U.S. Energy Secretary Ernest Moniz has said he thinks grid-scale battery storage will be the key innovation that enables the grid to completely decarbonize by mid-century.
http://spectrum.ieee.org/energywise...-plan-to-build-a-battery-the-size-of-the-grid
 

ctg

Ylipäällikkö
#69
In a development beneficial for both industry and environment, UC Santa Barbara researchers have created a high-quality coating for organic electronics that promises to decrease processing time as well as energy requirements.

"It's faster, and it's nontoxic," said Kollbe Ahn, a research faculty member at UCSB's Marine Science Institute and corresponding author of a paper published in Nano Letters.

In the manufacture of polymer (also known as "organic") electronics - the technology behind flexible displays and solar cells - the material used to direct and move current is of supreme importance. Since defects reduce efficiency and functionality, special attention must be paid to quality, even down to the molecular level.

Often that can mean long processing times, or relatively inefficient processes. It can also mean the use of toxic substances. Alternatively, manufacturers can choose to speed up the process, which could cost energy or quality.

Fortunately, as it turns out, efficiency, performance and sustainability don't always have to be traded against each other in the manufacture of these electronics. Looking no further than the campus beach, the UCSB researchers have found inspiration in the mollusks that live there.

Mussels, which have perfected the art of clinging to virtually any surface in the intertidal zone, serve as the model for a molecularly smooth, self-assembled monolayer for high-mobility polymer field-effect transistors - in essence, a surface coating that can be used in the manufacture and processing of the conductive polymer that maintains its efficiency.

More specifically, according to Ahn, it was the mussel's adhesion mechanism that stirred the researchers' interest. "We're inspired by the proteins at the interface between the plaque and substrate," he said.

Before mussels attach themselves to the surfaces of rocks, pilings or other structures found in the inhospitable intertidal zone, they secrete proteins through the ventral grove of their feet, in an incremental fashion.

In a step that enhances bonding performance, a thin priming layer of protein molecules is first generated as a bridge between the substrate and other adhesive proteins in the plaques that tip the byssus threads of their feet to overcome the barrier of water and other impurities.

That type of zwitterionic molecule - with both positive and negative charges - inspired by the mussel's native proteins (polyampholytes), can self-assemble and form a sub-nano thin layer in water at ambient temperature in a few seconds. The defect-free monolayer provides a platform for conductive polymers in the appropriate direction on various dielectric surfaces.

Current methods to treat silicon surfaces (the most common dielectric surface), for the production of organic field-effect transistors, requires a batch processing method that is relatively impractical, said Ahn. Although heat can hasten this step, it involves the use of energy and increases the risk of defects.

With this bio-inspired coating mechanism, a continuous roll-to-roll dip coating method of producing organic electronic devices is possible, according to the researchers. It also avoids the use of toxic chemicals and their disposal, by replacing them with water.

"The environmental significance of this work is that these new bio-inspired primers allow for nanofabrication on silicone dioxide surfaces in the absence of organic solvents, high reaction temperatures and toxic reagents," said co-author Roscoe Lindstadt, a graduate student researcher in UCSB chemistry professor Bruce Lipshutz's lab.

"In order for practitioners to switch to newer, more environmentally benign protocols, they need to be competitive with existing ones, and thankfully device performance is improved by using this 'greener' method."
http://www.spacedaily.com/reports/Inspiration_from_the_ocean_999.html
 

ctg

Ylipäällikkö
#71
Koska kyse on elektrolyytistä tämän pitäisi teoriassa myös parantaa luontaismateriaalista kuin hampusta taikka merilevästä tehtyjä akkuja/super capasitors.

Various nanomaterials have been drafted into the quest to improve the charge capacity of anodes (negative electrodes) in lithium-ion batteries. Their role primarily has been to help silicon—which offers ten times the charge capacity of graphite—last more than just a few charge/discharge cycles. Everything from graphene to nanofibers have been enlisted into help silicon better survive the rigors of the expansion and then contraction that occurs when silicon anodes are charged and discharged.

Now scientists at Columbia University have developed a nanostructure for the silicon anode of Li-ion batteries that will help them overcome one of their most challenging moments: the very first charge/discharge cycle that occurs during manufacturing.

It is in the manufacturing process of Li-ion batteries where the batteries first lose their energy capacity. After a Li-ion battery is first produced, it is goes through its first charge/discharge cycle so that part of its liquid electrolyte is reduced to a solid and that coat the anode of the battery. This process irreversibly depletes the amount of energy a battery can store by 10 percent for regular anodes but as much as 20 to 30 percent for next-generation silicon-based anodes.

“Through our design, we've been able to gain back this loss, and we think our method has great potential to increase the operation time of batteries for portable electronics and electrical vehicles,” said Yuan Yang, an assistant professor at Columbia, in a press release.

In research described in the journal Nano Letters, Yang and colleagues fabricated a three-layer structure for the anode consisting of silicon, lithium, and a polymer coating called PMMA (Polymethyl methacrylate). PMMA remains stable even in ambient air, providing a longer lasting battery that is cheaper to manufacture.

The battery industry has traditionally dealt with the problem of energy loss during the first charge/discharge cycles by adding more lithium-rich materials to the electrode. However, this was problematic because these materials are not stable in ambient air. In order to create conditions in which lithium-rich materials would not react to the moisture in the air, industry would create perfectly dry environments, which increased manufacturing costs.

The new tri-layered electrode structure developed by the Columbia researchers uses the PMMA to ensure that the lithium is not exposed to ambient air or moisture. The polymer layer is covered with an active material that can be artificial graphite or silicon nanoparticles. The polymer layer then dissolves in the electrolyte of the battery, which then exposes the lithium to the electrode.

“This way we were able to avoid any contact with air between unstable lithium and a lithiated electrode,” Yang explained. “So the trilayer-structured electrode can be operated in ambient air. This could be an attractive advance towards mass production of lithiated battery electrodes.”

The measured effects of this tri-layered structure for the manufacturing process are pretty striking. In state-of-the-art graphite electrodes the loss of capacity went down from 8 percent to 0.3 percent. The impact is even more dramatic in silicon-based anodes where the loss of capacity went from 13 percent to minus 15 percent, meaning that the electrode had more lithium than it actually needed. This extra bit of lithium comes in handy later in the batteries life after many charge/discharge cycles.

In continued research, Yang and his Columbia colleagues are looking to make the polymer layer even thinner and in so doing take up less room in the battery. The researchers are also looking at ways that they can scale up the technique.
http://spectrum.ieee.org/nanoclast/...e-makes-batteries-better-on-very-first-charge
 

ctg

Ylipäällikkö
#72
The Z-machine. Muutama vuosi sitten tästä ei voinut puhua kuin foliohattu päässä, koska top secret, mutta nyt.

Using magnetic field thermal insulation to keep plasmas hot enough to achieve thermonuclear fusion was first proposed by the Italian physicist Enrico Fermi in 1945, and independently a few years later by Russian physicist Andrei Sakharov.

An approach known as magneto-inertial fusion uses an implosion of material surrounding magnetized plasma to compress it and thereby generate temperatures in excess of the 20 million degrees required to initiate fusion. But historically, the concept has been plagued by insufficient temperature and stagnation pressure production, due to instabilities and thermal losses in the system.

Recently, however, researchers using the Z Machine at Sandia National Laboratories have demonstrated improved control over and understanding of implosions in a Z-pinch, a particular type of magneto-inertial device that relies on the Lorentz force to compress plasma to fusion-relevant densities and temperatures. The breakthrough was enabled by unforeseen and entirely unexpected physics.
http://www.spacedaily.com/reports/B...n_stability_opens_new_path_to_fusion_999.html

The researchers' approach to fusion relies on laser preheating of the fuel contained within a solid cylindrical metal liner, both of which are pre-magnetized by a magnetic field of 100,000 Gauss- a crucial distinction.

Applying a force of 20 million Amperes over 100 nanoseconds causes the liner to implode, compressing the plasma and raising temperatures to 30 million degrees and magnetic flux to 100 million Gauss. When the fusion yield is large enough, such an enormous magnetic field is able to trap the heat given off by the fusion reactions and "boot-strap" itself to higher temperatures, leading to ignition of the fuel.

According to existing theory, however, the imposed magnetic field should not have significantly impacted the growth of the instabilities that normally shred the liner and prevent high levels of compression during the implosion.

But, while fusion plasmas are subject to various forms of instability, referred to as modes, not all these instabilities are detrimental. The pre-magnetized system demonstrated unprecedented implosion stability due to the unpredicted growth of helical modes, rather than the usual azimuthally-correlated modes that are most damaging to implosion integrity.

The dominant helical modes replaced and grew more slowly than the so-called "sausage" modes found in most Z-pinches, allowing the plasma to be compressed to the thermonuclear fusion-producing temperature of 30 million degrees and one billion times atmospheric pressure. The origin of the helical modes themselves, however, remained a mystery.

Advanced simulations of the system solved the mystery by uncovering the origin of the helical instability growth that enabled high temperatures, magnetic fields, and plasma pressures from such high-convergence implosions.
 

ctg

Ylipäällikkö
#73
Lithium/rikki akkuteknologia on noin kaksi kertaa parempi perinteiseen lithium/koboltti yhdistelmään verrattuna.


Researchers have built a prototype lithium-sulphur battery that — when perfected — could have up to five times the energy density of current lithium-ion devices. Researchers in the UK and China drew inspiration from intestines to overcome problems in the battery construction.

In your intestine, small hair-like structures called villi increase the surface area that your body uses to absorb nutrients from food. In the new lithium-sulphur battery, researchers used tiny zinc oxide wires to form a layer of material with a villi-like structure. These villi cover one electrode and can trap fragments of the active material when they break off, allowing them to continue participating in the electrochemical reaction that produces electricity.

Lithium-sulphur batteries aren’t new (in fact, they were used in 2008 in a solar-powered plane that broke several records), but this new technique may make them more practical. You can see a video about ordinary lithium-sulphur batteries below along with more on how this research improves the state of the art.

A typical lithium-ion battery contains graphite and lithium cobalt oxide. Positively charged lithium ions move back and forth from the cathode, through the electrolyte and into the anode. Since the carbon atoms in the graphite can only take (at most) one lithium ion, that sets the theoretical limit on how much energy you can draw from the battery.

Sulphur and lithium react differently, via a multi-electron transfer mechanism. That’s why sulphur can offer a much higher theoretical capacity. However, as the battery undergoes several charge-discharge cycles, bits of the sulphur break away causing the battery to gradually lose active material. The zinc oxide villi tend to trap these pieces which slows the degradation of the battery.

The villi improved the number of times the prototype battery can be charged and discharged, but it is still not able to match a conventional lithium-ion battery. On the other hand, the new battery doesn’t need recharging as often.
http://hackaday.com/2016/11/01/new-lithium-battery-technology-takes-guts/
 

ctg

Ylipäällikkö
#74
Grid-scale energy storage is the lesser-publicized half of the clean energy story. As solar and wind farms scale up, so does the grid’s need to put electricity on layaway for those nights and cloudy and windless days when solar and wind farms lie fallow. Storing electric power via flywheels, compressed air, superconductors, pumped water reservoirs, thermal storage, hydrogen gas, and even rocks on railcars are methods being researched—and in some cases, commercially prototyped today.

But ARPA-E, the U.S. Department of Energy’s technology incubator, retains a strong focus on the familiar electrochemical battery as a likely backbone of an increasingly solar and wind-powered electric grid of the future.

A report published by ARPA-E earlier this year outlines the $85 million in R&D funding it’s invested in battery-based grid storage since 2009. The report details the agency’s grid-scale battery plans, including projected system costs, which they say should eventually drop by at least an order of magnitude compared with 2010. That, say ARPA-E researchers, would allow them to become viable commercial players in the years ahead.

According to Eric Rohlfing, ARPA-E’s Deputy Director for Technology, some technologies they’ve invested in are headed that way. But he notes that the agency backs portfolios of projects, and is not in the business of picking single winners in any category. “One of the things that we like to say we do at ARPA-E is we provide technological options,” Rohlfing says. “As much as we love many of these projects, for me to look into a crystal ball and say, ‘This particular chemistry, this particular flow battery will be the answer,’ I think is premature.”
http://spectrum.ieee.org/energywise/green-tech/fuel-cells/challenging-the-lithiumion-boom
 

ctg

Ylipäällikkö
#75


Jayan Thomas, an associate professor at the University of Central Florida’s (UCF’s) NanoScience Technology Center, has devoted a fair amount of his recent research to developing nanoprinting techniques to produce high-density supercapacitors. Thomas and his colleagues at UCF have been following that up with research in the area of supercapacitors aimed at creating nanowire-enabled cables that can both conduct and store energy.

Now Thomas has kept on this supercapacitor theme, but this time has taken some inspiration from the pop culture—namely the movie Back to the Future Part II—to create garments that can serve as solar-powered batteries that would never need to be plugged in.

“That movie was the motivation,” said Thomas in a press release. “If you can develop self-charging clothes or textiles, you can realize those cinematic fantasies—that’s the cool thing.”

In research published in the journal Nature Communications, Thomas and his UCF colleagues developed a ribbon-like device that can harvest light, convert it into electricity, and then store that electricity
http://spectrum.ieee.org/nanoclast/...tion-for-clothing-with-a-solarpowered-battery

The work is remarkably reminescent of research presented back in September. Researchers created a woven material comprising two power-generating components: fiber solar cells and a triboelectric generator that produces energy through static electricity. However, that device did not have any energy storage element.

In this latest research, a power generation layer is joined to an energy-storage layer. The ribbon integrates a perovskite solar cell with a supercapacitor via a copper ribbon which functions as a shared electrode for direct charge transfer.
“A major application could be with our military,” Thomas said. “When you think about our soldiers in Iraq or Afghanistan, they’re walking in the sun. Some of them are carrying more than 30 pounds of batteries on their bodies. It is hard for the military to deliver batteries to these soldiers in this hostile environment. A garment like this can harvest and store energy at the same time if sunlight is available.”

In a telephone interview with IEEE Spectrum, Thomas did concede that at this point, the supercapacitor was not capable of storing enough energy to replace the batteries entirely, but could be used to make a hybrid battery that would certainly reduce the load a soldier carries.

Thomas added: “By combining a few sets of ribbons (2-3 ribbons) in parallel and connecting these sets (3-4) in a series, it’s possible to provide enough power to operate a radio for 10 minutes. Currently these devices are not optimized for providing the highest energy and power density. However, we are working on improving the energy density so that it can work as a hybrid battery-supercapacitor device.”
 

ctg

Ylipäällikkö
#76

How to dispose of nuclear waste is one of the great technical challenges of the 21st century. The trouble is, it usually turns out not to be so much a question of disposal as long-term storage. Disposal, therefore is more often a matter of keeping waste safe, but being able to get at it later when needed. One unexpected example of this is the Bristol team's work on a major source of nuclear waste from Britain's aging Magnox reactors, which are now being decommissioned after over half a century of service.

These first generation reactors used graphite blocks as moderators to slow down neutrons to keep the nuclear fission process running, but decades of exposure have left the UK with 104,720 tons of graphite blocks that are now classed as nuclear waste because the radiation in the reactors changes some of the inert carbon in the blocks into radioactive carbon-14. Carbon-14 is a low-yield beta particle emitter that can't penetrate even a few centimeters of air, but it's still too dangerous to allow into the environment. Instead of burying it, the Bristol team's solution is to remove most of the c-14 from the graphite blocks and turn it into electricity-generating diamonds. The nuclear diamond battery is based on the fact that when a man-made diamond is exposed to radiation, it produces a small electric current. According to the researchers, this makes it possible to build a battery that has no moving parts, gives off no emissions, and is maintenance-free.

The Bristol researchers found that the carbon-14 wasn't uniformly distributed in the Magnox blocks, but is concentrated in the side closest to the uranium fuel rods. To produce the batteries, the blocks are heated to drive out the carbon-14 from the radioactive end, leaving the blocks much less radioactive than before. c-14 gas is then collected and using low pressures and high temperatures is turned into man-made diamonds. Once formed, the beta particles emitted by the c-14 interact with the diamond's crystal lattice, throwing off electrons and generating electricity. The diamonds themselves are radioactive, so they are given a second non-radioactive diamond coating to act as a radiation shield.
http://www.bristol.ac.uk/news/2016/november/diamond-power.html
 
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miheikki

Ylipäällikkö
Lahjoittaja
#77
Kävi tuo minullakin mielessä. Itseasiassa taisin joskus tuoda esille ajatuksen, että pitäisi olla keino, jolla muuntaa polttopuun polttamisesta tuleva lämpö sähköksi. Silloin mietin, että olisiko syytä harkita höyrykoneiden uutta tulemista, mutta kun kerran tuollainen keksintö on saatavilla, niin mitäpä turhia.
MIkro CHP https://en.wikipedia.org/wiki/Micro_combined_heat_and_power

https://www.theseus.fi/bitstream/handle/10024/20523/mikro-chp-raportti_nro8.pdf?sequence=3


Ongelmana näissä liika lämmöntuotto kesällä.
 

ctg

Ylipäällikkö
#78
For several decades now, scientists from around the world have been pursuing a ridiculously ambitious goal: They hope to develop a nuclear fusion reactor that would generate energy in the same manner as the sun and other stars, but down here on Earth.

Incorporated into terrestrial power plants, this "star in a jar" technology would essentially provide Earth with limitless clean energy, forever. And according to new reports out of Europe this week, we just took another big step toward making it happen.

In a study published in the latest edition of the journal Nature Communications, researchers confirmed that Germany's Wendelstein 7-X (W7-X) fusion energy device is on track and working as planned. The space-age system, known as a stellerator, generated its first batch of hydrogen plasma when it was first fired up earlier this year. The new tests basically give scientists the green light to proceed to the next stage of the process.
http://www.space.com/34960-star-in-a-jar-fusion-reactor-works.html
 

ctg

Ylipäällikkö
#79
Emerging markets are leapfrogging the developed world thanks to cheap panels.


A transformation is happening in global energy markets that’s worth noting as 2016 comes to an end: Solar power, for the first time, is becoming the cheapest form of new electricity.

This has happened in isolated projects in the past: an especially competitive auction in the Middle East, for example, resulting in record-cheap solar costs. But now unsubsidized solar is beginning to outcompete coal and natural gas on a larger scale, and notably, new solar projects in emerging markets are costing less to build than wind projects, according to fresh data from Bloomberg New Energy Finance.

The chart below shows the average cost of new wind and solar from 58 emerging-market economies, including China, India, and Brazil. While solar was bound to fall below wind eventually, given its steeper price declines, few predicted it would happen this soon.
https://www.bloomberg.com/news/arti...-turning-point-solar-that-s-cheaper-than-wind
 

ctg

Ylipäällikkö
#80
It would be a lot easier to expand our use of solar and wind energy if we had better ways to store the large quantities of electricity we’d need to cover gaps in the flow of that energy.

Even in sunny Los Angeles, a typical house roofed with enough photovoltaic panels to meet its average needs would still face daily shortfalls of up to about 80 percent of the demand in January and daily surpluses of up to 65 percent in May. You can take such a house off the grid only by installing a voluminous and expensive assembly of lithium-ion batteries. But even a small national grid—one handling 10 to 30 gigawatts—could rely entirely on intermittent sources only if it had gigawatt-scale storage capable of working for many hours.

Since 2007, more than half of humanity has lived in urban areas, and by 2050 more than 6.3 billion people will live [PDF] in cities, accounting for two-thirds of the global population, with a rising share in megacities of more than 10 million people. Most of those people will live in high-rises, so there will be only a limited possibility of local generation, but they’ll need an unceasing supply of electricity to power their homes, services, industries, and transportation.

Think about an Asian megacity hit by a typhoon for a day or two. Even if long-distance lines could supply more than half of the city’s temporarily lowered demand, it would still need many gigawatt-hours from storage to tide it over until intermittent generation could be restored (or use fossil fuel backup—the very thing we’re trying to get away from). Li-ion batteries, today’s storage workhorses in both stationary and mobile applications, are quite inadequate to meet those needs. The largest announced storage system, comprising more than 18,000 Li-ion batteries, is being built in Long Beach for Southern California Edison by AES Corp. When it’s completed, in 2021, it will be capable of running at 100 megawatts for 4 hours. But that energy total of 400 megawatt-hours is still two orders of magnitude lower than what a large Asian city would need if deprived of its intermittent supply. For example, just 2 GW for two days comes to 96 gigawatt-hours.

We have to scale up storage, but how? Sodium-sulfur batteries have higher energy density than Li-ion ones, but hot liquid metal is a most inconvenient electrolyte. Flow batteries, which store energy directly in the electrolyte, are still in an early stage of deployment. Supercapacitors can’t provide electricity over a long enough time. And compressed air and flywheels, the perennial favorites of popular journalism, have made it into only a dozen or so small and midsize installations. We could use solar electricity to electrolyze water and store the hydrogen, but still, a hydrogen-based economy is not imminent.

And so when going big we must still rely on a technology introduced in the 1890s: pumped storage. You build one reservoir high up, link it with pipes to another one lower down and use cheaper, nighttime electricity to pump water uphill so that it can turn turbines during times of peak demand. Pumped storage accounts for more than 99 percent of the world’s storage capacity, but inevitably, it entails energy loss on the order of 25 percent. Many installations have short-term capacities in excess of 1 GW—the largest one is about 3 GW—and more than one would be needed for a megacity completely dependent on solar and wind generation.

But most megacities are nowhere near the steep escarpments or deep-cut mountain valleys you’d need for pumped storage. Many, including Shanghai, Kolkata, and Karachi, are on coastal plains. They could rely on pumped storage only if it were provided through long-distance transmission. The need for more compact, more flexible, larger-scale, less costly electricity storage is self-evident. But the miracle has been slow in coming.
http://spectrum.ieee.org/energy/ren...-get-biglike-enormousfor-solar-power-to-shine