Verdens største vannkraftverk

Foto: Le Grand Portage

De tre kløfters demning i Hubei, Kina er et av verdens største demninger og vannkraftverk. Det ligger langs verdens tredje lengste elv, Chang Jiang. Reservoaret dekker området som heter de tre kløfter, som ligger mellom byene Yichang og Fuling.

Byggingen av demningen ble ferdigstilt i 2006. Vannmagasinet er 660 km langt og lagrer i snitt 39,3 kubikkilometer vann. Kraftproduksjonen i tilknytning til vannmagasinet skal gi ca. 85 TWh.

Om lag 1.4 millioner mennesker måttet flytte til andre deler av Kina for å gi plass for demningen. I 2007 annonserte kinesisk medier at anslagsvis 4 millioner mennesker ville bli tvunget til å forlate sine hjem grunnet en «mulig miljøkatastrofe». Vannkvaliteten i Yangtze-elva faller hurtig; alger blomstrer og jorderosjon fører til at elveleier faller sammen og forårsaker jordras. Kinesiske forskere og embetsmenn uttalte av demningen kunne føre til en «enorm katastrofe ... om ikke noe ble gjort omgående».

Problemene til tross, denne dokumentaren er en fascinerende gjennomgang av vannkraft generelt og et enormt prosjekt:

Verdens største vannkraftverk

21:58 Energiproduksjon , Ingeniørkunst

Life on Mars

Det blir kanskje litt mye SpaceX for tiden, men gårsdagens hendelse var en milepæl for dette prosjektet. Ifølge fremdriftsplanen går første ferd i 2022 og kanskje ser vi byen ovenfor i løpet av noen tiår:



Mars | SpaceX

Life on Mars

22:33 Fremtidsscenarier , Gigantbygg , Ingeniørkunst

Kjører mer enn 100 km på en liter

XL1 er Volkswagens nye elhybrid, og den må nok regnes som et eksperiment. Bilden bruker bare 0,9 liter diesel på å tilbakelegge 100 km. Et strømlinjet design og spesialutviklede lettvektsmaterialer er noe av hemmeligheten.

Bilen skal produseres i kun 250 eksemplarer, hvilket nok bidrar til den temmelig stive prisen på rundt kr 750 000,- ­

Kilde: Illustrert Vitenskap

Kjører mer enn 100 km på en liter

20:20 Ingeniørkunst

Android-huset er på vei

Android@home er i korte trekk en utviklingsplattform for å gjøre Android-apparater som mobiltelefoner og tablets i stand til å kontrollere ting du har i hjemmet. Dette kan være alt fra lyspærer og termostat til musikkanlegg og vaskemaskin. Utviklingsplattformen blir helt åpen, slik at det er fritt frem for både privatpersoner og bedrifter å lage programvare - og produkter - for plattformen.

Google har ikke satt noen dato for når du kan forvente en Android@Home-løsning som nærmer seg ferdig, men der er grunn til å anta at Google kommer med noe mer konkret i løpet av overskuelig fremtid.

Selskapet Lightning Science har allerede vist frem en LED-lyspære som kan slås av og på via Android, og som skal være på markedet allerede før årsskiftet.

Kilde: Mobili.no

Android-huset er på vei

18:09 Ingeniørkunst

Interaktiv arkitektur

Via Spaces of Performance

Interaktiv arkitektur

20:47 Ingeniørkunst , Installasjoner

U2 360-degrees Space Station

Jan Gradvall skriver i Expressen U2s sceneshow, bygget opp rundt en konstruksjon som han sammenligner den franske kunstneren Louise Bourgeois spiders.

Scenen er konstruert slik at delene kan beveges for dermed å gi publikum på baksiden av stadioner den samme opplevelsen som de som står foran.

Mark Fisher writes:

My first sketches for the U2 360º tour were made during the fifth (Australian) leg of the Vertigo tour, in November 2006. The first (USA) leg of the tour had been staged ‘in the round’ in arenas. When the tour moved to Europe, it was restaged as a conventional end stage stadium show. In the process, it lost much of the intimacy of the arena shows. As the tour travelled through Australia, Willie Williams and the band discussed the feasibility of playing stadia ‘in the round’. The band was looking for a way to regain some of the audience contact that they had lost, without compromising the scale of a big stadium show. Playing arenas ‘in the round’ is easy, because the arena roof provides rigging points for the loud speakers and lights required for the show. This leaves the sightlines between the audience and the stage unobstructed, and the band free to perform facing in any direction. To create a 360º show in a stadium it is necessary to find some way to support all the equipment above the band. The traditional way of doing this is to build a conventional touring roof over the stage and accept that the supporting towers will obstruct sightlines from a large number of seats.

Willie realised that one answer to the 360º challenge would be to build a structure that spanned the whole stadium floor off very skinny legs. He found inspiration in the shape of the LAX Theme restaurant. Opened in 1961, the building is a multistory structure with the circular restaurant cantilevered from a cylindrical service core and partly supported on four reinforced concrete legs. The arched forms of the legs are extended over the roof of the restaurant to form a decorative crown. The dominant form of the vaulting arches combines with the played down form of the service core to create the impression that the restaurant floats above the surrounding car parks, supported only by the legs. Willie imagined a similar structure, with the legs spanning clear across the full width of a football field so that both band and audience stood beneath the structure. He first discussed his idea with Hedwig de Meyer (President of StageCo) who was visiting the tour in Aukland, New Zealand, and later with Jake Berry. Neither of them demurred, and the first I heard of it was an email from Willie asking for some sketches.


The big difference between what Willie was proposing and the LAX building was that whereas the restaurant rotunda is supported on the service core, we wanted the space beneath the centre of the superstructure to be clear. This meant that all the loads in our superstructure had to be transferred down the legs to the ground. My first sketches established the scale and feasibility of the basic structure. They were well received by the band, which gave Willie and me a mandate to carry on exploring the idea.

In our early conversations, Willie and I discussed possible alternatives to on-stage video, including a proposal to treat the 360º audience as a giant screen for video projection. In 2007 I began playing with the idea of see-through planar screens hanging beneath the structure in the void over the stage. At first I imagined that these would be developed from the roll-up 360º video screens that we had built for the USA leg of the Vertigo tour in 2005. But around that time I was working with Chuck Hoberman on a kinetic sculpture for the Wynn Resort in Las Vegas, and also spending a lot of time in Beijing with Frederic Opsomer. Frederic had long been interested in the possibility of creating an LED video screen that would have variable density, so it was a short step to introduce him to Chuck’s work. By the end of the year I was sketching planar and 3d versions of Hoberman scissor geometries over the stage.

By the end of 2007 the scale of the over stage structure was clear, but the question of form remained. Willie and I both felt that the structure needed to be expressive, even decorative, and to avoid the rock ‘n’ roll cliché of trusses with lights. But in the absence of any clues from the band about a theme for the upcoming tour, it was not easy to find a direction. Over the winter, Willie and I discussed the design at length. In January 2008 I emailed him: “The big challenge with creating a rock show is that… the design parameters are either arbitrary, or functional. In the sense that a show can be about anything or nothing, they are arbitrary. In the sense that the logistical aspects of how to package and tour the show are significant parameters, they are functional. To move the design discussion of a rock show beyond functionality it is necessary to address the arbitrary, and this is not easy. Unlike an aeroplane, or a hospital operating room, a rock stage can be absolutely anything; in the end it all comes down to taste.”

In a conscious attempt to move away from the orthogonal language of touring structures, I aimed for something streamlined. By March 2008 the design had crystallized into a simple curving form that discretely expressed the structural forces beneath. My first 3d CAD model studied both the proportions and the logistics of the structure, and set both the overall dimensions and the sizes of the main components. It was based on large truss elements that could sit side by side on a flat-bed truck, overlaid with hard-shell cladding panels. The key to successfully touring such a large structure would be to get the build sequence correct from the beginning. At each venue the build would take place in two stages. I proposed that so far as it was possible, the first stage; the building of the main structure, would take place at ground level. The completed, clad structure would then be lifted into the air, successive leg sections being added during the lift until the completed structure could be dropped onto the feet. The second stage; the loading in of the production equipment (sound, lights and video screen) would then take place with the crew working at height from the protected catwalks inside the structure.

In April 2008 Hoberman and I sketched a number of alternative designs for articulating LED screens. By the end of the month Willie and I had settled on a truncated elliptical cone shape, and Chuck’s team came up with a several different ways of applying LED panels to the scissor mesh surface. They all derived from Frederic’s original concept for a screen that could change density from 100% solid to something closer to 50% transparent. At the same time Adrian Mudd began making presentation animations of the stage and screen, and Jeremy Lloyd and Atelier One reworked my original CAD model into a detailed design and engineering model. By the end of April we had a presentation ready for the band, and prices and truck estimates for both the steelwork and the cladding. Jake Berry took our numbers and fed them into his live Nation touring budget, but (the band being a little bit late with the album) we were unable to stage a show-and-tell, and so the whole project went to sleep over the summer.

Reasoning that playing a stadium ‘in the round’ would require twice as much PA as an end-on show, my original design was based on duplicating the PA used for the Rolling Stones’ ‘Bigger Bang’ stadium stage. In late June Clair Brothers came back to Stufish with a detailed design for the PA that almost doubled the number and weight of the PA over my original estimate (thus employing four times the amount of PA used on the Bigger Bang tour). Incorporating this much larger PA into the project required a major redesign of the superstructure.

We finally got a sign off from the band in September 2008, and work started on the detailed design of all the elements. A three day meeting at Hoberman’s office in New York early in October outlined the critical parameters for the articulating screen. Unlike any of the structures that Chuck had built before, the scissor mechanisms would have to break apart into pieces that fitted into scenery carts that would themselves fit onto airfreight pallets and into trucks. And it would have to be completely assembled in less than eight hours, sometimes on the morning of showday. Richard Hartman and Nick Evans joined the team to bring their touring experience to bear on what was obviously a complex collection of problems that needed solving in a very short time. Everyone understood that unless we were cutting metal by January, the frietzak (as the mesh basket had been christened in honour of its Belgian parentage) would not be completed and tested in time for the start of rehearsals on 1 June 2009.

The final design of the video screen divides it horizontally into four tiers, and vertically into 24 columns. Each column is made up of four panels, one for each tier, each panel being approximately 3m long x 1.5m tall when closed. Each tier of 24 panels packs into eight scenery carts. Each panel is attached to its neighbours on either three or four sides, the joints are moment connections either at the hinge points or at the mid-points of the scissor beams. The panels are suspended from a mother truss that houses the 36 chain hoists employed to expand and contract the Hoberman screen scissor mechanism. The chain hoists are programmed to follow a position table created by Buro Happold, holding their positions to within 5mm as the screen articulates. The mother truss also houses video power and distribution racks. The truss is suspended from the main octagon truss of the superstructure by eight winches, each carrying a load of four tonnes.

By the end of September most of the design strategy for the superstructure and screen had been worked out; the only outstanding issue was the cladding and thus the final appearance of the structure. The cost of building and transporting hard-shell cladding was prohibitive, and the need to find a different way of covering the superstructure opened a way for me to develop a more interesting proposal. Willie and I presented my first version of a push-out polyp tensile structure to the band at a meeting in New York in late October. It was not an easy sell. The new illustrations showed a structure that was not only less neutral than the hard-shell proposals, it was also something novel. The original proposal carried within it a memory of the LAX theme building but the new design had no formal antecedents. It was an expressive solution to the functional challenges of low packing volume and fast assembly.

The band bought the concept and we presented a detailed video animation to them at Olympic Studios in November. It illustrated how audience sightlines worked from all positions in the stadium, and also explained the articulation of the video screen and the stage architecture. By this time we had worked out the performance stage in detail. The elliptical stage would be surrounded by an elliptical ‘B’ stage runway accessed by arched bridges spanning over a mosh pit. The bridges were designed to move around the stage like the hands on a clock face so that the band could access them from any point on the stage or runway. The movement of the bridges presented an interesting technical challenge as they moved around an elliptical path.

The tensile membrane cladding of the superstructure does not provide any weather-cover for the band beneath. To keep the band and backline equipment dry, I proposed to Willie that we resurrect the centre-draining inverted umbrella design used on the 1977 Pink Floyd USA tour. The umbrellas were invented by Frei Otto in 1971 for a garden exhibition in Germany. The nine umbrellas used on the Pink Floyd tour were engineered by Ian Liddel at Buro Happold. They stored below the stage and deployed through hatches in the floor, opening at different heights to create an overlapping umbrella field. We decided to use three 4.8m diameter umbrellas with a 600mm overlap. One umbrella is centred on Larry’s drum riser, the other two are located upstage of Adam and The Edge’s backline stacks. The umbrella under the drum riser revolves with the drum riser when Larry turns to face upstage.

The final design of the membrane and polyp positions was complete by the end of December, allowing David Dexter Associates to start work on the detailed form-finding. By the start of January StageCo were cutting steel for the primary structure and Innovative Designs were cutting aluminium for the frietzak screen. Willie and I presented a range of membrane/polyp colour schemes to the band in February. After a scary moment during which it seemed as if they were going to choose the safe option of grey and silver, they voted for a combination of two separate schemes, pairing an eau-de-nil skin with safety orange polyps and silver-grey legs.

The subdivision of the superstructure and technical equipment for the show into two classes of touring equipment, universal production and steelwork, was the same as for similar large stadium rock tours. We would build three complete sets of superstructure, red, green and blue, named after the steel teams that would look after them. These sets of steelwork would ‘leap-frog’ between cities, each one taking four days to build and two days to take down, with one day in the middle for production load-in and one day for the show. Everything else, the video screen and its automation package, the four-sided PA, the lighting rig, the performance stage and the entire barricade, would be toured as universal production, to be loaded in during the 36 hours preceding the show. In the end, the universal production totalled 57 trucks, a demonstration of the fact that playing a show 360º requires almost twice as much equipment as playing at one end of a stadium.

The test-build of the first of the three steel superstructures took place in Werchter, Belgium in May 2009. This was followed by the first assembly of the frietzak in Antwerp later the same month. By the end of the month the structure had been lifted to full height, set on its feet and the cigar, complete with lights, hoisted into place. The testing of the frietzak was delayed by the loss of a consignment of LEDs in a cargo plane crash in Japan, but on June 1st Willie and I witnessed a full test of the expanding screen with full video running. The frietzak was dismantled and trucked to Barcelona, where it was rigged beneath the steel superstructure for the first time on 8th June. On 16 June the band walked the stage for the first time, 40 weeks after they signed off on the project in September 2008.

During the time that had elapsed since the band signed off the design, the new album ‘No Line on the Horizon’ had been released, the show had been christened U2 360º, and a tour logo had been developed that was loosely on the superstructure design. The emotional direction of the tour, an optimistic salute to the future, was now clear. On the night of the dress rehearsal on 29 June, Bono christened the stage set the U2 Space Station. The show opened before a capacity crowd of 90,000 people at Camp Nou, Barcelona, on 30 June 2009.

Vital statistics:
The superstructure
Across stage width across bases - 64m (210ft)
Up/down stage width across bases - 48.5m (159ft)
Height of superstructure - 30m (100ft)
Height to lightening conductor (tip of pylon) - 51.8m (170ft)
Clear span across stage -57.5m (189ft)
Clear span up/down stage - 41.5m (136ft)
Height to underside octagon truss - 25m (82ft)
Tip to tip length of pylon - 43m (141ft)
Total unladen weight of superstructure - 190 tonnes

The video screen
The screen is made of 1,000,000 different pieces:
500,000 RGB pixels
320,000 Fastners
30,000 connecting cables
60,000 off-the-shelf items (connectors, bearings etc.)
90,000 custom-fabricated components
25 km of cable inside the structure
3 km of aluminum profiles
Weight of video screen frietzak - 32 tonnes
Weight of video screen mother truss - 20 tonnes
Video screen flown weight - 52 tonnes
Total video screen weight including distro, automation & winches – 74 tonnes

Production load
Total production load applied to superstructure
(PA, lights, video screen, cigar, winches & automation) - 176 tonnes
Thus the flown production load (which is normally loaded in during the 24 hours preceding the show) weighs almost as much as the superstructure that it is hanging from.


Mark Fisher Studio

360.u2.com

Expressen.se

U2 360-degrees Space Station

22:54 Ingeniørkunst

Ulike tiltak for geonengineering

Geoengineering, det vil si ideen om at man kan kontrollere Jordas klima med ulike tekniske virkemidler, har i det siste fått vind i seilene. At et økende antall forskere ser ut til å mene at den globale oppvarmingen er irreversibel i overskuelig framtid er en viktig årsak til dette.

En teknikk går ut på å gjøre skylaget mer reflekterende:

En gruppe forskere har publisert en 50 siders rapport som rangerer de mest aktuelle geoengineering-teknikkene i tidsskriftet Atmospheric Chemistry and Physics.

Forskernes utgangspunkt er at den økte mengden CO₂ som er sluppet ut siden industrialderen begynte rundt 1800, har sørget for at 1,6 Watt per kvadratmeter holder seg i Jordas atmosfære. Om dagens CO2-nivå dobles (hvilket NASAs James Hanson ikke holder for usannsynlig), vil dette tallet øke til 3,71 W. Deretter regnet forskergruppen ut hvor mye hver geoengineering-teknikk ville bidra til å redusere disse tallene. Resultatet ble listen som er publisert her.

Det viktigste man kan lese av listen er at det er langt mer effektivt å reflektere mer sollys tilbake til verdensrommet enn å binde opp mer CO₂.

2050 - Forskere rangerer geonengineering-tiltak

Ulike tiltak for geonengineering

18:18 Forskning , Fremtidsscenarier , Ingeniørkunst

Får vi nye initiativ for bølgekraft?

Norge har de aller beste forutsetninger for å produsere bølgekraft. En lang kyst og teknologimiljøer med omfattende erfaring i å utvikle maritime konstruksjoner burde være en bra kombinasjon

På 1980-tallet ble det bygget to demonstrasjonsanlegg på Toftestallen, på Turøy utenfor Bergen. Det ene anlegget ble bygget av Kværner i 1985. Dette anlegget baserte seg på at bølgebevelsene ble overført til en luftsøyle inne i et vertikalt rør - et såkalt Oscillating Wave Column (OWC) system. Luftstrømmen ble så brukt til å drive en Wells turbin, en metode som minner om den løsningen som er valgt for et anlegg på Pico, Azorene.


Kværners anlegg sto ved det blå merket på bildet, mens restene av Norwaves anlegg er lett synlig - Se større utsnitt

Kværners hadde en gjennomsnitlig effekt på 500 kW og var i drift fra 1985 til 1988 da anlegget ble ødelagt under en kraftig storm.

Det andre anlegget på Turøy, TAPCHAN (TAPered CHANnel), ble bygd i 1986 av firmaet Norwave. Konseptet var basert på at bølgene ble presset opp gjennom en kileformet renne, slik at vannet havnet i et bassent 3 meter over havflaten. Denne høydeforskjellen ble utnyttet ved å slippe vannet ut gjennom en turbin. Tanken var at dette anlegget skulle tjene som modell for tilsvarende anlegg i den tredje verden. Også dette anlegget hadde en effekt på 500kW og var i drift fra 1987 til 1991. Anlegget ble ødelagt i forbindelse med utvidelsesarbeider som ikke ble sluttført (BT.no).

Norske teknologimiljøer har utviklet en rekke prosjekter, noen av dem svært lovende. Utviklingen synes imidlertid å ha stoppet opp, og vi er i ferd med å bli hentet inn av andre land. Vi skal ikke lenger en utenfor kysten av Cornwall for å finne eksempler på det. Her har briteneetablert testsenteret Wave Hub, der det Fred Olsen-eid selskapet Fobox er involvert:

- Vi vil gjerne fortsette utviklingen av vår teknologi i Norge, men kan av forretningsmessige årsaker slik forholdene er nå, ikke unngå å legge virksomheten til Storbritannia, sier prosjektleder Tore Gulli i Fobox.

Foxboxs pongtongbaserte «bølgekraftplattform» regnes som et av de aller mest lovende bølgekraftteknologiene, og de er ett av fire selskaper som på invitasjon fra britene deltar på Wave Hub.

Pelamin Wave Power er også et selskap som synes å ha kommet langt med sin teknologi:



Kraftløs bølgekraft - Teknologi og Verkstedindustri�

Får vi nye initiativ for bølgekraft?

18:17 Energiproduksjon , Ingeniørkunst

New York - London på 54 minutter, med tog!

Et tog drevet fremover av magnetfelt kan i teorien gjøre unna distansen New York til London på 54 minutter, ifølge dette programmet fra Discovery Channel.

Forutsetningen for at dette skal være mulig er imidlertid nærmest science fiction. Topphastighten må være rundt 3000 km/t, det må bygges en undersjøisk (flytende) tunnell som er nærmere 2000 km lang.

Ifølge denne dokumentaren skal dette kunne la seg gjøre.

Se også de relaterte videoene for dokumentaren i sin helhet.

New York - London på 54 minutter, med tog!

13:13 Ingeniørkunst , Transport

Kraftlinje med design

- Vi har ikkje berre fått folk til å akseptera kraftlina, dei likar henne og seier dei heller vil ha kraftlina enn eit tomrom, seier Bjørn Ekelund, planleggingsarkitekt hos det svenske arkitekt- og konsulentfirmaet SWECO, til Bergens Tidende.

SWECO sitt forslag til kraftlinje er ikke realisert, foreløpig finnes abre en modell og fotomontasjer. En kan trolig også innvende at konstruksjonen eger seg dårlig i et klima hvor det kan være fare for isdannelse. Designet synes imidlertid å vekke begeistring, også hod de som i utgangspunktet er negative til nye kraftlinjer.

- Det vanlege er at folk opplever at kraftliner tar plass, at dei er stygge og farlege. I Luleå opplever vi at folk likar forslaget til ny kraftline. /../ Vi har sett på kva mogelegheit arkitektar har til å påverka opplevinga av installasjonar som dette, og vi ser at utforminga er heilt avgjerande for korleis folk opplever situasjonen, sier Bjørn Ekelund.

-Det vil bli bruk for fleire kraftliner i åra som kjem. Difor er det viktig å diskutera både omfanget og utsjånaden på desse. Vi trur vi har starta ein debatt i rett tid, og ser at fleire svenske kraftselskap er i ferd med å tenkja nye tankar på dette området. Snart vil vi også sjå resultat av dette. I framtida kan vi få kraftliner som er utforma slik at konfliktnivået i utbyggingssaker vert redusert

Kraftline som begeistrar - bt.no

Kraftlinje med design

20:17 Industridesign , Ingeniørkunst

400 km/t, to meter over havet

Såkaltet "wing-in-ground"-fly kan fly lange avstander bare få meter over havoverflaten, ifølge Newscientist. Flyene utnytter et fenomen som kalles "bakke-effekten", som skapes når turbulens fra vingene brytes av bakken. Dette øker oppdriften drastisk og gjør at flyet kan bevege seg langt raskere fremover.

Tongji University planlegger å utvikle et 50-seters WIG innen 2013, og prototyper som kan frakte 200 til 400 tonn innen 2016-2017.

I den kalde krigen utviklet det russiske militæret et WIG-fly (se bildet). Det såkalte Ekranoplan. Dette var rundt 100 meter langt og kunne frakte 540 tonn i 400 km/t.

TU.no - Flyr to meter over havet - Teknisk Ukeblad

400 km/t, to meter over havet

17:52 Ingeniørkunst