energia nuclear

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EL ACCIDENTE NUCLEAR DE FUKHUSIMA

El brutal terremoto que ha azotado Japón recientemente ha traído un corolario inesperado: Un accidente nuclear en la central de Fukushima en la isla principal de Japón y a 240 km al noreste de Tokio. Cuando se escriben estas notas (la situación cambia con tanta celeridad que lo que se escribe estará viejo cuando se lea) el reactor número 1 del complejo atómico (que consta de 6 grupos en funcionamiento y dos más en construcción) parece ser el más dañado. Aunque la reacción nuclear se detuvo como consecuencia del terremoto, el sistema de refrigeración del núcleo, cuya función es extraer el calor residual de la reacción nuclear, se ha visto severamente afectado.  El problema, aún ahora es ¿Cómo conseguir extraer el calor del núcleo del reactor para evitar que se funda completamente y libere una ingente cantidad  de radiactividad?.

Pero hay que aclarar que una buena cantidad de materiales radiactivos ya han sido liberados, y en el momento en que se escriben estas notas se ha publicado que hay tres personas hospitalizadas, que entre 70 y 160 están expuestos a niveles de radiación por encima de lo previsto y unas 200.000 personas, en un radio de 20 km han sido desalojadas de sus hogares.  Aunque la AIE de la energía ha calificado el suceso  como nivel 4 en su escala de sucesos nucleares, no es difícil adivinar que esta calificación será revisada al alza ya que el suceso es, en el momento presente, más grave que  el de la central nuclear de Three  Mile Island, Harrisburg (Pensilvania,  EE.UU) de 1979 que oficialmente tiene la calificación de nivel 5.

Hay un elemento de morbo adicional en nuestro país. La central accidentada es gemela de la planta de Santa María de Garoña (Burgos), la más antigua de las que aún funcionan en la península y sobre la pesa una orden de cierre decretada por el gobierno actual y que debe ser ejecutada por el que le suceda en las próximas elecciones. El líder de la oposición, hasta ahora, ha hecho gala de pretender la prolongación de la vida de la central nuclear. Ambas centrales son de agua en ebullición de patente General Electric  de potencia similar y de casi la misma antigüedad. Ambas se conectaron a la red eléctrica en 1971.

El origen de los problemas parece haber sido, tras la parada de la planta como consecuencia del movimiento sísmico, la pérdida del suministro eléctrico exterior con el que funciona el sistema de refrigeración de emergencia (el que extrae el calor residual del núcleo cuando se ha detenido la reacción nuclear). Para agravar las cosas se produjo una posterior pérdida del generador diesel  para alimentar eléctricamente dicho sistema, como consecuencia del Tsunami  que siguió al terremoto.  

Hay algunas preguntas que merecen respuesta. ¿Por qué de los 6 reactores del complejo el más severamente dañado es el grupo número 1? .Y otra no menos importante ¿A qué se debió la explosión que ha afectado a la contención exterior de la planta?.

Las respuestas a estas preguntas es, sorprendentemente, muy relevante para el futuro de la central nuclear de Garoña. Una de las muchas mentiras que se contó a la opinión pública europea tras el accidente de Chernobil, es que ese accidente no podría ocurrir aquí porque todas las centrales disponían de sistemas de contención que laminarían la fuga de material radiactivo que se produciría tras un accidente nuclear. Se hablaba de de que todas disponen de sólidos edificios de hormigón armado (contenciones secas) capaces de soportar el incremento de la presión y las posibles explosiones de origen químico que seguirían a  un accidente nuclear. Esto era evidentísimamente falso en Zorita (cerrada en 2006) ya que disponía de una cúpula de acero de apenas unos centímetros de espesor, y era también mentira en Fukushima y en Garoña porque disponen de un sistema de contención denominado Mark I que funciona por el mecanismo de relajación de presión.

En este sistema hay una doble contención. La primera es una envoltura hermética de acero (ver “Informe sobre las centrales nucleares españolas”de marzo de 1983 del CSN) dotada de una cámara de relajación de la presión que no es sino una vasija de acero llena hasta la mitad de agua. En el exterior hay una segunda contención de hormigón armado de 1 m de espesor. Esta segunda contención (que como se ha visto  no es una sólida contención de hormigón amado y que tampoco está dotada de una sólida cúpula semiesférica) es la que ha sido dañada (parece que definitivamente destruida) por una explosión que después trataremos de explicar.

Al contrario de lo que han dicho en muchas ocasiones los cínicos portavoces de la industria nuclear y del supuesto organismo de control (el CSN), la contención que funciona de forma eficaz no es la secundaria, ya destruida en el accidente, sino la primaria. En la página 64 del citado informe del CSN se puede leer que esta contención está diseñada para soportar presiones y temperaturas que resultarían de un fallo equivalente a una rotura circunferencial de la tubería principal de refrigeración y la consiguiente emisión de gases de la vasija del  núcleo. Estos gases son sobre todo vapor de agua, pero también isótopos volátiles y el hidrógeno que se forma en la propia reacción nuclear y además tras la reacción del metal que forma las vainas de combustible con agua al elevarse la temperatura del núcleo. Este hidrógeno es el problema.

La filosofía de relajación de la presión es que estos gases al burbujear forzosamente sobre el agua de la vasija de acero se enfrían (parte del vapor de agua vuelve a ser líquida) o se disuelven en agua. Este es el caso del yodo, uno de los radioisótopos más abundantes en los productos de fisión del uranio que presenta una notable solubilidad en agua. El problema es justamente el hidrógeno. Este gas ni se licua ni se disuelve y su proporción en la contención primaria aumenta. Es bien sabido que dicho gas produce, cuando se alcanzan ciertas proporciones, una reacción explosiva con el oxígeno del aire. Este parece ser el origen de la explosión que ha destruido la contención secundaria. La proporción hidrógeno/oxígeno ha resultado fatal. El oxígeno, poco presente en la contención primaria, está no obstante en el aire a presión reducida de la contención secundaria. El hidrógeno apareció en dicha contención por “venteo” de la contención interior para aliviar la presión en el interior de la misma.

No es difícil entender algunas de los fragmentos de noticias que se están produciendo. Se habla de aumento de la radiación exterior y esto se debe a los “venteos” de gases que arrastran materiales radiactivos del núcleo, sobre todo productos de fisión volátiles. Parecen coherentes las noticias que haban de niveles altos de Yodo y Cesio en el entorno. Y se ve con gran preocupación como continuar la  refrigeración del núcleo. Muy probablemente deberán producirse nuevos “venteos” de gases radiactivos para evitar que la sobrepresión sobre la contención primaria provoque una fuga masiva (como la de Chernobil)    de radioisótopos.  Es, sin lugar a dudas una decisión prudente ventear, pero  cada vez que se hace aumenta el impacto radiológico del accidente. Por eso lo de evacuar a 200.000 personas es una decisión valiente y acertada. Se ha primado su seguridad pese a la evidente alarma social que concita la medida.

Mientras escribo estas notas deseo fervientemente que los técnicos de Fikushima, que están sufriendo riesgos radiactivos por los que muy probablemente pagarán en el futuro, logren refrigerar la central nuclear. Es verdad que el tiempo corre a nuestro favor, que en el núcleo cada vez hay menos calor residual y que refrigerarlo debe ser cada vez más fácil…si la contención primaria no está demasiado dañada y si no surge un nuevo imprevisto.

Espero también firmemente que el suceso tenga la trascendencia que merece en nuestro país y que la central gemela de Fukushima, Garoña, cumpla el calendario de cierre establecido.  

Ladislao Martínez López

Cementiri nuclear d'Ascó

Adjunto un petit article que he rebut i em sembla interessant:


 

Cal tenir en compte que dels 9 reactors que hi ha a Espanya, Catalunya en té 3 i representen el 40% de la potència instal·lada.

Hom pot pensar que som molt generosos en fer tant electricitat per Espanya, però el cert és que consumim el 36% de l'energia elèctrica nuclear que es fa a Espanya, és a dir gairebé tota la que produïm.
 
De fet, el 60% de la producció elèctrica a Catalunya és d'origen nuclear. Contrasta amb la d'origen renovable (solar, eòlica, biomassa i termosolar) que només és de l'1,5% (sense comptar la hidroelèctrica, és clar).
 
La producció elèctrica depèn de la potència elèctrica instal·lada. Però aquesta no és una relació lineal. Les nuclears tenen una producció contínua, però les renovables (inclosa la hidroelèctrica) no. Les centrals tèrmiques s'utilitzen om a reguladors d'aquestes oscil·lacions. Per tant, les centrals tèrmiques que cremen combustibles fòssils no renovables i que contribueixen a l'escalfament global són la clau de volta del sistema energètic català.
 
Així doncs, la potència elèctrica instal·lada a Catalunya de tipus nuclear representa el 27% del total. I això és perquè hi ha una sobredimensionada potència elèctrica de centrals tèrmiques no renovables, en concret un 44%, que serveix desistema amortidor. Les hidroelèctriques tenen el 20,5%. Cal una potència elèctrica més alta en renovables per suplir els moments d'inactivitat, però tot i així tant sols representa el 7,86%.
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Joy, clay and nudity: a weekend in the woods with LGBT faeries of color | World news “R evel in your faggotry!” This was the commandment given to us at the beginning of Xrysalis: Gathering of Queer People of Color, an event taking place last week in the Redwoods of Mendocino County, about 100 miles north of San Francisco. The weekend had some ground rules: no white or straight people were allowed to watch us partying, dancing or doing drag. We would be, if only briefly, entirely free from the white heterosexual gaze – a new experience for many of the 50 participants. Instead, Xrysalis was reserved for radical faeries of color. According to William Stewart, a member of the Groundswell Institute, which hosted the event, the radical faerie tradition can be traced to the Gay Liberation Front. The word “faerie” was a reclamation of being swishy, Stewart explained, and a form of rebellion against hypermasculinity. As a movement, radical faeries are supportive of communal sex, communal living, and communing with nature, positioning themselves at odds with the consumerist, monogamous marriage equality movement. Many people involved with Groundswell have been involved with “gatherings of radical faeries” at Wolf Creek, Oregon and Short Mountain, Tennessee – bacchanalian gatherings of hundreds of queers in nature. Others have lived in radical faerie houses in cities. pre bonded hairLocated on 200 acres, the venue looks like a kids’ campground – but there are tell-tale signs that something else is going on. Condoms and lube are available in the dining hall. Clothing is optional, and the bathrooms are gender-neutral (and will soon have group showers and a sauna). And it’s not unusual to see goats or alpacas being cared for by a farmhand wearing little more than nail polish and a jockstrap. It’s a beautiful sight, and the fresh goat milk is delicious. Participants relax by a lake. Photograph: Bonita Tindle Since covering the Orlando shooting, I’ve been thinking about how I often write about queer people of color in the context of abuse, murder, and the plague of HIV - yet rarely in moments of exploration or joy. Reveling in “faggotry”, hedonism or nature is not something many of the people attending the festival are used to being encouraged to do. As the artist Favianna Rodriguez once told me: “We are told by society that pleasure is the domain of white men” and that brown bodies simply need to “be productive”. For a few days, though, we queers of color shared, talked, sang and danced – just as co-organizers Grace Towers, blue buddha, Jimmy Hill and Ernesto Sopprani dreamed we could. And, with the help of dressing up in drag, soaking up nature, slathering our bodies in clay and skinny dipping, we got to question what it is like to be a queer person of color in a world that erases us. How do we process fears of violence? And what can we do to find joy regardless? These are some of our stories as we addressed these que(e)ries. Jimmy Hill

David (left) and Jimmy. Photograph: Bonita Tindle “It is very lonely to be in a group of people where none of them are reflecting yourself back,” Jimmy Hill explained, talking about going to his first gathering of radical faeries last year at Saratoga Springs. He is a dark-skinned, beautiful black man with a full beard and a fuller smile, and his life was changed by the event. However, “there was that one piece that was missing: other folks of color”. He did not feel seen by white faeries, and if any were interested in him, “it was purely physical, and they didn’t want to know the person behind the body”. Disturbed that they could be “free in a way that we’re not”, including “having access to spaces like this in nature”, he started to dream up Xrysalis. “If you live in all-white spaces, if you don’t reflect back what they are giving you, you become a threat to them. And a lot of black gay men, out here in California who have a lot of white friends, they are just trying to survive. And when you get in contact with another black person, or a group of black people, that in and of itself is calling attention to you and your blackness – and that is a threat to whiteness,” he said. Jimmy wanted to seek healing in nature. “From losing a generation to HIV to mass incarceration, we’re getting wiped out right in front of people’s eyes, and people aren’t doing anything about it other than posting something or playing Pokémon Go,” he worried. To gather community, he feels, is a solid counterpoint to those frustrations. Snowflake Towers remy hair extensionsSnowflake Towers. Photograph: Bonita Tindle When asked in a workshop about what she would do if she only had 48 hours to live, Snowflake Towers said: “I’d want the world to know that gay sex is sacred, and I’d spend it having a lot of gay sex. And you’d all be welcome to join in,” she added with a laugh. Snowflake believes that “faggots are magical creatures”. But in a drumming and chanting ceremony around the fire, Snowflake (who is of native Tzeltal Mayan ancestry on her father’s side and Yaqui on her mother’s) attempted to disabuse us of the idea that practicing “faggotry” in nature is any way tied to whiteness, or even to maleness. “Gender didn’t exist the way we see it now in western culture,” she explained. “Most tribes didn’t have a concept of one or the other, and you could change midway, because gender is a spectrum.” While drumming, Snowflake invited everyone to list their genealogy, in whatever language they come from. We are a diverse group of queers: Native and Afghani and Pakistani and black, who have come to “Turtle Island” (an indigenous term for North America) through migration and slavery and travel. “When people can find and start to decolonize and strip all that bullshit off of themselves, then can find out who they are and really revel in their faggotry,” she said.

Jamel Sellitti Jamel with his crown. Photograph: Bonita Tindle One morning, about 30 of us gathered in the sun for yoga, beneath a rainbow flag. Despite how it is marketed, it is ridiculous to think of doing yoga en masse as something for white people, given that it originated in ancient India. Led by a beautiful Afghani man named Nakh Ter, the class was a display of beautiful brown skin stretching beneath the sun – some muscled, some hirsute, some tattooed, some scarred. Sellitti wore a crown of blue flowers on his head – as the US army veteran did for the whole weekend, and as he also does in his largely black San Francisco neighborhood of Bay View. The crowns “represent my emancipation from society”, he said, explaining: There were three gay people in my hometown, all of them white. Growing up, hanging out with these people, I would go to clubs and bars and see them get picked up by other white people very easily. I often was like, why is that not me? I felt like my life was in their hands, in a sense, meaning they dressed me up and made me be how they thought I should be. Jamel arrived with his three black best friends. Having this squad, coming to a space just for people of color, and wearing flowers all are acts of resistance to assert who he is on his own terms. Musing on violence (he’s from Florida and had been to Pulse), he believes Americans are violent to people of color because they’re “scared of us. They’re not scared of us in the sense that we’re black or brown or not white. I think they’re scared of us because they see potential in us, and I think because of that, they feel threatened.” Ms Thrash Her Ms Thrash Her. Photograph: Bonita Tindle perruques cheveux naturelsAfter Jamel gifted me a flower crown, I thought about how much I love seeing black men wear flowers. As a black writer who receives a lot of pushback for writing with anger, I am aware that it’s dangerous to be seen as the “angry black man”. But I’m equally aware that it’s difficult to be vulnerable in a world that wants me to be hard. I then visited Groundswell’s onsite “Drag Lab”, which is full of wigs, clothes and shoes for any visitor to use. I used to be very uncomfortable with the idea of drag, and never thought I’d do it myself. And when I first announced I was gay, it was important to me to be seen as a “man”, and to expand what that word that could entail. But the older I get, the less I find being a “man” or embodying “masculinity” work as concepts which serve me (or the world) very well. And while I’ve grown used to wearing boots with rainbow stockings (my go-to outfit for Pride and Burning Man), I decided to go a bit further in my “Ms Thrash Her” persona, adding a black lace skirt, purple wig, and church lady hat to my wardrobe. When I posted a picture of my outfit, the artist Frank J Miles captioned it “Make America America again” – which warmed my queer heart after writing about Donald Trump. blue buddha “I found love for the first time at age 50, and it was five months ago”, said blue buddha, one of Xrysalis’s co-organizers, as he led a workshop about relationships. “And it was with that man over there.” Blue points to David, who is also a big, handsome, black man with a full gray beard. “Growing up, to me, gay was white skin,” he later tells me. His sexuality “never felt right until I found ‘queer’.” As a psychotherapist, blue helped design the gathering, thinking of watching police shooting videos was doing to the black psyche. “A lot of anxiety has ramped up,” he says. “It’s like a low-grade PTSD, because there is the anxiety that something bad is going to happen, and it keeps getting closer every time we hear about it.” “It gets whitesplained away, governmentsplained away, bullshitsplained away,” he says. “But it’s like a shell game with our emotions. We’re living in this fear – and we need a break to heal,” he says passionately. I confess to him my guilt at going to Burning Man, when I think I should be out covering the movement or marching myself. But he says it’s important for people of color to renew themselves in places like this because “getting into nature does amazing things for people”, “it’s important to know that we are not alone”, and we need “to know that we can lead a different life, that a different life is possible”. Jay Renee Cambridge

David and Jay. Photograph: Bonita Tindle On a hot Saturday afternoon, the retreat gathered at a beautiful private pond where, apart from the few who sat in a carpeted, Bedouin-style tent overlooking the water sipping lemonade, most people stripped and jumped in the water. “It was an amazing experience, just seeing all the beautiful shades of brown and everyone embracing their own skin,” Jay Renee Cambridge told me. Jay is a transgender veteran of the US air force who was disciplined during Don’t Ask, Don’t Tell. “I came knowing no one, and left with family,” said Jay, who drove almost 700 miles from Las Vegas to attend the gathering after simply Googling “trans retreat”. Xrysalis marked Jay’s “first time stripping all the way, and just jumping in the pond, and it felt great. It was really liberating, being able to express my true authentic self.” This was a change from when, “about a year ago, I was a little self conscious even after top surgery”. Back then, before taking his shirt off, Jay wondered, “Will people judge me because of my scars? Are they going to ask, ‘What are those scars from?’ But now, they’re a part of me and I just embrace every part of that.” perruques cheveuxAfter diving into the pond naked, Jay was touched to hear people say, “Thank you. It was courageous and inspiring to see you, and it gave me the courage to strip down, too.” I concurred. Clothed and walking around in the world, I usually hate my body: the size of my belly and my butt; the lack of hair on my head; and the abundance of hair on my back and backside. But here, I felt less self-conscious than ever. It was not like being at Fire Island or a gay pride march, where buff, hypermasculine white men are centered and everyone else compares themselves to them. Here, whiteness was absent; there were bodies with lots of body hair and none, bodies with big asses and big boobs and both (and neither), with genitals of all varieties, with no one around to pathologize them. The scene grew even more magical when huge buckets of clay appeared and everyone started to cover one another’s body in it. It felt wonderfully indulgent to feel the clay cool before it slowly started to bake in the sun. I watched it caking on the thigh of Brontez, a beautiful black man lying next to me in the sun; the variations of brown cracks on his skin looked as stunning as the surface of a planet photographed from a satellite. “Your skin looks like the surface of Venus,” I told him. “Hottentot?” he said with a laugh. Grace Towers

Steven Thrasher with Grace Towers Photograph: Bonita Tindle The last night of Xrysalis, there is an outdoor drag show which looks little like what you’d see on RuPaul’s Drag Race. For one, the queens are not trying to look like blonde, skinny white women. Some are more bearded than Conchita Wurst, and the outline of a penis can appear as prominent bulge rather than being tucked away. These faeries of color can also scream “Yaaaaas!” to their hearts’ delight without worrying about white gay people stealing it. lace front wigsGrace Towers, a first-generation Mexican queen whose people come from Guadalajara, embodies a “hypermasculine, hyperfeminine” presence. She goes through several costume changes, wearing a full, dark beard against a long wig and a housewife’s frock. “It’s so amazing so many of you showed up,” the co-organizer says. “I’ve never been to a place just for queer and trans people of color before. How many of you have?” Only one person raises their hand, hesitantly – explaining it was an event for people of color, of whom many were queer.

After acts of drag, music and poetry, Grace performs the final number with one last costume change. She wears a sexy dress, but her beard is covered by what looks like the face mask of a medieval knight’s helmet. She thrashes so physically to the violent song that by the time it is done, she is panting. After applauding, the audience is so stunned that the only sound which can be heard between her gasping breaths is of the crackling fire. “My heart is so fucking full right now,” she says. “And I’m so tired of missing people who could be here, of having moments of silence for those who can’t be here. Instead of being silent, I invite you to scream.” On the count of the three, the fire-lit faces of 50 queer people of color let out the kind of primal screams that leave your throat feeling raw the next day. cosplay wigsTo me, they are screams for the dancers at Orlando, Islan Nettles, Philando Castile and Sandra Bland. Yells for all the ways black and queer people feel unseen and unable to breathe in America. And they are screams for the joy and exuberance of finding one another. Then, after the screams, we dance under the bright moonlight, finally free for a moment, until the wee hours of the morning.