POWER PYLONS OF THE FUTURE
Building cri cal infrastructure such as power lines - in and around communi es is always going to be challenging. But important decisions – on how we balance the need for new infrastructure with its costs and impact on the local environment – simply can’t be avoided.
Steve Holliday, CEO Na onal Grid
They have to be made if we are to meet customers’ needs and ensure the lights stay on. From: Powering Britain’s Future: Listening and ac ng, Interim Report October 2013
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100.000 PYLONS NEEDED BY 2020 - IN EUROPE ALONE
The transi on from fossil fuels to renewable energy calls for a worldwide large-scale expansion of the power transmission grid - the interconnec ng motorways of high voltage. In Europe alone, 28.000 km of 400 kV transmission line is needed by 2020 to fulfil
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the aim of providing 20 percent of Europe’s energy from renewable sources such as solar power, hydro power and wind power. This corresponds to the distance from London to Perth and back.
Extending the European transmission grid requires a new type of pylon. A Pylon that is easier to erect, less costly and be er looking than the old ones must be made available if we are to meet consumer demands - and ensure the lights stay on.
It also means that more than 100.000 new pylons will be needed. 5
BYSTRUP has been working on the power pylons of the future for more than a decade. This booklet tells the story of the latest product developments in power transmission in our pursuit of a worthy replacement for the conven onal la ce tower.
TIME FOR CHANGE
A SUPERIOR ALTERNATIVE TO THE LATTICE TOWER All over the world people nowadays find la ce towers intrusive and very o en oppose them fiercely. This makes life difficult for Transmission System Operators (TSO’s) trying to meet the huge demand for new lines that carry renewable energy from produc on sites to popula on centres. By Kenn Andersen, Construc on Manager, BYSTRUP.
A historic monument - the laƫce tower - sƟll dominates the scenery. Its construcƟon has proven its worth for more than a century. Even in the 21st century, laƫce towers are seen as the easy and predictable soluƟon…
How hard can it be to come up with a superior alterna ve to the la ce tower? The challenge is not to create a visual alterna ve. Anybody will understand that this is not the difficult part. The real challenge is to create a power pylon bea ng the la ce tower on any parameter.
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BYSTRUP is one of the very few professional companies in the world exclusively focused on designing, developing, planning and erec ng radically innova ve power pylons. We are experienced in what it takes to develop an idea from the ini al vision to a finished design which incorporates all the necessary technical specifica ons. We have set up a framework of guidelines for developing power pylons that combine aesthe cs, engineering and environmental awareness. For more info: www.powerpylons.com
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Small, eec ve, cost-compe ve, and elegant. These are the overall criteria any BYSTRUP pylon must meet.
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A POSITIVE IMAGE
FRONT RUNNER IN THE FIELD OF PYLONS The powerline is designed as a row of monopile structures with filigree la ce heads in stainless steel tubes.
The Pylon Family Three types of towers were developed:
By grouping the conductors in a triangular cross sec on, the electromagne c field is minimised. As a result, the Design Pylon is dis nc ve, simple and func onal.
Flying angle tower for maximum 5o devia on
Henning Øbro, Senior Execu ve Project Manager, Energinet.dk.
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In 2001, the Design Pylon wins the internaƟonal compeƟƟon organised by Danish TSO Energinet.dk and the Danish Ministry of Environment and Energy.
During the material selec on, several op ons were inves gated. The final choice was hot-dip galvanised steel for the sha and stainless steel for the la ce top.
As the name ‘Design Pylon’ suggests, the main focus of the compe on was originally on aesthe cs.
The pylon is reduced to a few elements calmly traversing the landscape.
The la ce head is constructed of stainless steel tubes joined by cast nodes: a simple and fast assembly method.
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Suspension tower
Angle tension tower for 5o to 45o devia on. A prototype of the suspension tower was constructed and mechanically tested to 105 percent of the maximum design loads. At present, 80 pylons have been erected, and have been very well received. For more informa on: www.energinet.dk
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Locals were involved in the whole process and have embraced the new pylons calling them ‘Magic Wands’. - Henning Øbro, Senior Execu ve Project Manager, Energinet.dk
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RENEWABLE-GRID-INITIATIVE (RGI) BEST PRACTICE IN GRID EXPANSION PROJECTS This change will have tremendous effects on the geography and me horizons for planning and implemen ng new electricity infrastructure.
New thinking is required to meet the challenges posed by increasing energy needs and climate change.
To fully integrate renewable energy from centralised and decentralised sources, Europe´s grid architecture needs to be adapted and expanded to allow transmission over long distances, across na onal borders, and from genera on to consump on and storage sites. Thousands of kilometres of new lines need to be built today and in coming decades. However, public opposi on is growing.
Europe is in the middle of a substan al transforma on of its energy system. In order to fight climate change, a strategy has been developed consis ng of three pillars: a reduc on of greenhouse gas emissions, more energy efficiency, and an increased share of renewable energy.
To overcome this opposi on, new alliances across society are needed. It is necessary to bring more transparency to the grid business, to further develop par cipatory procedures and to redefine roles which have been performed over the past decades. RGI has provided a forum, in which
By Antonella Ba aglini, Execu ve Director, Renewables-Grid-Ini a ve.
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Transmission System Operators (TSOs) and non-governmental organisa ons (NGOs) can prac ce their new roles. RGI was launched in July 2009 by a coali on of four members - two TSOs and two NGOs. For the first me, these two groups defined their common interest in the 100%-integra on of renewable electricity into the European grid and commi ed themselves to working together. Since then, RGI has grown to include 15 members from all over Europe. TSOs have learned that they need to overcome the ‘business as usual’ approach and respond to the new situa on in a flexible way. Civil society, on the other hand, recognises that it needs to inspire the transforma on, explain it and help build support among the general public. A major step for this coopera on was the publica on of the ‘European Grid Declara on on
Electricity Network Development and Nature Conserva on in Europe’ in November 2011. Building on commitments made in the ‘European Grid Declara on’, RGI ini ated an exchange of best prac ces in grid expansion projects across Europe in 2012. The coopera on between grid operators and civil society during the past four years has shown that unexpected success can be achieved if different stakeholder groups team up.
However, some challenges s ll remain unsolved. The diverging actors involved in grid planning s ll lack common ground on a variety of topics. Joint understanding of challenges need to be developed and agreed upon by TSOs, NGOs and further stakeholders. RGI will keep up its work to support this process. For more informa on: www.renewables-grid.eu
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The “European Grid Declaration on Electricity Network Development and Nature Conservation in Europe” was handed to former European Commissioner for Energy, now Vice-President of the European Commission, Günther H. Oettinger on November 10th, 2011 at the European Grid Conference in Brussels.
SAVE TROUBLE
AND WIN PUBLIC APPROVAL
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end of the line or where it goes underground a substa on and a terminal tower are established.
A new type of power pylon was developed: The Eagle Pylon designed by BYSTRUP.
Public acceptance The first public hearing, where different tower types and ideas were presented was held in June 2009. The mee ng gave the affected an opportunity to hear about the project and to ask ques ons regarding the overall project and the more local ma ers.
Due to local opposi on to la ce towers, the inten on was to create a new, calm, less intrusive and elegant power line.
By Christian Jensen, Executive Project Manager, Energinet.dk.
A single circuit line was to be replaced by a double circuit 400 kV power line desƟned to be the backbone of the Danish transmission grid connecƟng Germany to Norway and Sweden.
The pylon is a structure based on a cylindrical sha and rhomboid sec on cross-arms. This par cular shape makes the cross-arms appear slimmer. The Eagle Pylon family consists of suspension, flying-angle and tension pylons. All family members present a close resemblance to each other due to an iden cal overall design. At the
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In the second public hearing in March 2010, the final design was presented, and the public was asked to share their view on specific alterna ves. The feedback towards the new design was overall posi ve.
When construc on started in 2012 at Energinet.dk, we were surprised that the locals did not, as usual, call in massively to complain. Our phones stayed mostly silent and among the few incoming calls some were praise‌ At Energinet.dk, our apprecia on is that the new power line has been well accepted by most neighbours, experts, contractors as well as by our own employees.
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The locals have shown not only acceptance but even approval. Many locals seem proud of this novel design. For more informa on: www.energinet.dk
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The Eagle Pylon is developed for a new 166 km line through Jutland in Denmark.
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The Eagle Pylon has proven that, by rethinking the design and the general approach to overhead lines, it is possible to get posi ve feedback. - Christian Jensen, Executive Project Manager, Energinet.dk
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SAVE TIME
ONE DAY, ONE TEAM, ONE PYLON The construcƟon of Power Pylons has tradiƟonally been a Ɵme consuming process. However, with modern manufacturing processes and elements that can travel on the roads in few pieces, it is possible to erect a pylon a day.
7:00 AM
11:30 AM
A BYSTRUP Power Pylon consists of as few elements as possible to minimise transporta on, construc on me and cost. A monopile founda on is rammed into the earth. In many cases it immediately provides a full strength founda on ready for the pylon.
3:00 PM
A mobile crane li s the sec ons of the monopile sha and cross arms into place. Construc on of the pylon is completed in one day by a single team. The pylon elements are fabricated by automated processes in controlled factory condi ons. This simplifies on site opera ons and saves on construc on labour.
3:15 PM
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4:30 PM
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SAVE MONEY
DEVELOPMENT OF A NEW FOUNDATION The foundaƟon is one of the more criƟcal structural components of the power pylon. Any overhead line founda on solu on must be robust enough to last the life me of the pylon, be capable of quick installa on, and minimise land use. Founda ons for offshore windmills are typically made with monopiles
driven into the seabed. Similarly, founda ons for pylons on land can be provided by a hollow steel tubular sec on hammered into the ground. A monopile founda on footprint is very small compared to a concrete plate founda on. The environmental impact -noise, possible site contamina on and temporary works - is subsequently smaller, and due to very limited excava on,
ground water problems are prac cally eliminated. For installa on, a steel monopile is delivered to the chosen site, where a crane uprights and places it in the driving posi on on the ground’s surface. The pile gripper holds the monopile in place whilst a crane li s a driving hammer onto the top of the monopile. The hammer then drives the monopile into the ground.
The foundation for a lattice tower takes approximately four weeks to produce.
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The hammer can achieve full founda on installa on in under an hour, depending on ground condions. Using this solu on, total installaon me including set-up of a full strength monopile founda on is approximately two to three days compared to the 28 days it would take for the concrete solu on to reach the requisite strength for pylon erec on.
A pneumatic hammer rams the monopile into the ground.
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Two prototypes of the Eagle Pylon were made. The first was of weathering steel with stainless steel cross arms. The second was of galvanised steel. The prototypes analysed visual impact and allowed mechanical tests to be performed.
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MATERIALS FOR THE FUTURE 80 YEAR LIFESPAN For a number of years, BYSTRUP has been building up a data bank on new materials, their characterisĆ&#x;cs and resistance in various environments. This knowledge, combined with advanced design, allows for a symbiosis between form and material that is of utmost importance in selec ng the op mal material for new pylons. Choosing materials with longer lifespans reduces the overall cost of a power line. It limits the environmental impact of produc on and of the disposal of materials.
When selec ng materials for a specific transmission line it is essen al to consider the local terrain and clima c condi ons. Materials used must be appropriate to their environment and allow for feasible construc on methods. At BYSTRUP we focus on materials with high corrosion resistance and low degrada on to prolong lifespan. These key a ributes are oered by the following materials: Hot-Dip Galvanised Steel Stainless Steel Weathering Steel Concrete Composite Material
Testing samples of materials enables a useful comparison of various coating systems and materials. It is important to study closely how they perform. This is one of the reasons for building mock-ups.
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From a sustainability point of view, metals in their purest form are preferable, especially those with a long lifespan as well as colours and textures that blend well into the natural environment. In collabora on with the client, the best applica on of the material is ensured for each case. Transporta on, maintenance, and energy cost savings can be maximised through the op mal material choice, whilst also providing the best possible aesthe c solu on.
DELIVERING TODAY MAKE IT HAPPEN
By Henrik Skouboe, CEO, BYSTRUP.
Developing power pylons for the future means creaƟng objects that balance aestheƟcs and technical opƟmisaƟon. During the design process, complex 3D geometries must be managed. The technical demands and handling of high-voltage clearances require thorough knowledge of rules, regula ons and standards.
For instance, we analysed the na onal code of prac ce regarding galloping in coopera on with Danish TSO, Energinet.dk, and through advanced simula ons we were able to document that the precau onary distance could be significantly reduced. This resulted in a more compact, lighter and less costly pylon.
We are capable of dimensioning all components and performing structural, as well as dynamic analysis of the en re pylon.
The development of the T-Pylon made us inves gate the use of SG iron for the nodes. SG iron has duc le quali es which make the material suitable in regard to fa gue assessments.
The design of an en rely new pylon provided us with the opportunity to op mise the opera on of the grid.
Efficient logis cs, simplicity and speed of construc on are determining factors in our aim to produce compe ve and cost-effec ve power pylons. Un l now, one of the great challenges of conven onal towers was the actual assembling and moun ng.
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These are a few examples of the many challenges we analyse and tackle. BYSTRUP aims to create highly qualified and less expensive solu ons.
The improvement made to the installa on of the cables on the pylons is an example of this. Our innova ve stringing tool is an element which a aches directly to the yoke plate of the insulator assembly and requires no further support. This means that the cable can be strung directly into place in a single procedure.
This new device replaces the conven onal stringing block which requires li ing apparatus and o en temporary superstructure to support it while the cables are transferred from the block to their clamps. The elimina on of this stage of the stringing process simplifies the procedure. As a result, the me-factor eďŹƒciency increases and the cost of establishing new power lines decreases.
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Our design approach does not simply focus on the result, but embraces technical challenges in the process leading to be er solu ons. We studied the construc on process closely and designed new tools to energise the pylons in the most eďŹƒcient way.
The cables of the Eagle Pylon are being strung in a few days.
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THE LANDSCAPE
AN AGENDA FOR THE ENVIRONMENT When planning a new power line or modifying an exis ng route, it is paramount to determine the characteris cs of the landscape: Open or closed? Narrow or wide? Uneven hills or a smooth plateau? Sloping or level?
“ By Anne Brunsgaard, Environmental Manager and Landscape Planning, BYSTRUP.
Compared to roads, railways and waterways, a high voltage line is visible from a far greater distance and stands out visually in a landscape.
It is essen al to acquire a spa al overview of the actual landscape and its various elements - on a local as well as regional scale. The analysis must take into considera on built-up areas and the aesthe cs of the landscape. This o en leads to various alterna ve proposals.
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It is not easy to accommodate the diverging interests of various stakeholders such as the owner of the land des ned to host the line, the neighbour looking at it every day, the environmental group defending the local fauna and flora, etc. Trying to make everybody happy o en results in unhappy compromises entailing shi ing heights of pylons and inconsistent visual ensembles. Our designs consist of a family of pylons with iden cal general appearance.
When all the pylons look similar to each other the line will appear as a stable and unbroken structure in the landscape.
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Our goal is to have very few dierent types within a pylon family - all of them with an iden cal overall appearance. It is essen al to view the pylon as part of a whole and not simply consider it as a separate element on its own. Only by doing so is it possible to create consistency in shape and form.
Our vision is to achieve harmony between what is man-made and the landscape.
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TIME FOR T
AND THE WINNER IS... place where the project is to be located and which it will respond to. In Pylons for the Future, there was no site – how were we to consider the designs? Secondly, there was the implicit asser on that there was something ‘wrong’ with the exis ng generic design – the la ce pylon.
By Bill Taylor, Architect and Partner, Taylor Snell LLP.
When I was asked to be the Architectural Assessor for the RIBA Pylon for the Future CompeƟƟon, I paused for thought. Firstly, this was an unusual compeon. Normally, teams are asked to put their minds to designing a building, or a piece of a city, or a bridge. There is nearly always a
Actually, I quite like the ‘standard’ la ce design myself. In their purest form they are structurally efficient, calm and elegant – especially at dusk when the almost transparent openness of the la ce can appear like a fine tracery against a clear silver sky. The problems come with the grotesque muta ons to their form that is o en necessary at each change of direc on of the conduc ng cables. Thirdly, was the winner we would chose ever to be built?
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Far too many architectural compe ons are nothing more than client pipe dreams, the energies and efforts of the teams being wasted on a project that never had a chance of being realised. Against these reserva ons was balanced the nagging ques on: is it possible to improve the technical performance and short-comings of the exis ng design? With Na onal Grid about to embark upon an enormous programme of new infrastructure investment in our country, in ever more demanding and sensi ve loca ons, now was a good me to ask! More than any architectural compe on, probably since the Sco Telephone Box, this was a chance for architects and engineers to consider the effect of their work on not just a single site, but on an en re na on’s landscape. No mean responsibility or task, the stakes were high – it was a ques on that needed to be answered.
250 submitted designs from around the world were whittled down to six finalists, and in the end the T-Pylon was declared winner of the competition.
Chris Huhne, Secretary of State and Nick Winser from Na onal Grid had both given their public backing to the project, their teams were in place and well organised and we were all set to go. I felt that if we could find a ‘worthy winner’, there was a strong chance that something could end up ge ng built and some answers might be found. The clients had an cipated the sensi vity of the subject well. Clearly this was a subject that was very close to the na on’s heart. As I soon discovered, an electricity pylon and the power lines it supports are highly technical pieces of engineering design. And whilst there might well be a ‘generic’ pylon type, there are almost countless variants upon this theme – the design must respond to changes in voltage, numbers of cables, alignment on plan and sec on, direc on, above ground, below ground etc. etc.
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It was really a ‘family’ of pylons that we were looking for – or rather, the design of a generic pylon type that could develop to become a coherent family. The compe on was open to all. One of the main challenges of the compe on therefore was to elicit crea ve and imagina ve designs that were also technically feasible, or at least, could be made to be technically feasible.
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It must be said that the compe on a racted both enormous public interest and a level of response from the design professions like no other architectural compe on that I can recall. Most compe tors interpreted the compe on to be about ‘appearance’ and aesthe cs – which in part it was. However, it became evident that the be er entries had ques oned the engineering principles and/or requirements as part of their design methodology. As we were looking to eventually choose a pylon with a view to ge ng it built, these were the ones that made the second stage.
The second stage involved teams developing their concepts in discussion with Na onal Grid and their engineering experts. New ideas and technologies were open to explora on, but so too were possibili es of new working prac ces from the NG engineering teams in response to these opportuni es. This was a very exac ng stage for the compe tors. The technical limita ons of some of the more compelling ideas soon came to the fore under closer and detailed scru ny. What visually appeared a most graceful response to the typical condi on, was in the next breath shown to be a fundamental limitaon to the atypical. As ever, some teams responded more posi vely to this process than others. Ul mately, the T-Pylon design from BYSTRUP emerged the clear winner. What set this proposal apart was its star ng point. The radically innova ve move here was the reassessment of the conductor/cable alignments, NOT the pylon shape – which was the result of this.
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By arranging the cables in a prisma c configura on, the heights of the pylons could be reduced by nearly 40%, the landtake and footprint of the power lines reduced, the EMF radia on levels reduced, the steel tonnage probably contained to no more than the la ce pylon. And, like nearly all good engineering, it was a very elegant, calm and natural visual solu on. It all seemed so obvious! Cost was not really a criteria in the compe on or the assessment. However, in T-Pylon, the generic approach is one that will hopefully prove to be inherently flexible and economic. In choosing T-Pylon, the panel felt that they had seen a concept that could develop into a family and that would be strong and robust enough to withstand the gruelling technical and commercial pressures that Na onal Grid would inevitably put it under in the development programme. BYSTRUP and Na onal Grid have, I understand, been making great progress since the compe on results were announced.
Chief Executive of National Grid Steve Holliday presents the T-Pylon to Prince Philip, Duke of Edinburgh, at the Royal Academy of Engineering.
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THE T-PYLON - A SUCCESS
INNOVATIVE DESIGN FOR NATIONAL GRID The T-Pylon is a structure with very few parts. We expect it to be constructed quickly and to require no maintenance. When I saw the design ini ally, I thought it would be quite a challenge to develop, par cularly the composite insulator units. Despite being referred to as the ‘diamond earrings’, they are actually quite large structures, 13 metres by 8 metres. By Peter Botsoe, Pylon Development Manager, National Grid.
NaƟonal Grid was looking for a modern 21st century pylon design that meets the aestheƟc requirements of today. We wanted an innovaƟve design concept that could be made in reality. In the T-Pylon we believe we have found it.
At first sight the design appears simple, especially considering its func on; however there were many challenges to address. When you look at the monopile design such as the T- Pylon, the first thing that strikes you is that all of the conductors are held from one a achment point; this is just unheard of. Tradi onally, the structure has three separate arms, each holding an individual conductor. We have had to look at this par cular connec on point and
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ensure its robustness and fa gue resistance. Complex analysis and physical loading tests have been carried out to simulate clima c condi ons such as high winds and ice loading. We have also inves gated how the structure performs dynamically under simulated vibra ons. We are very confident that the T-Pylon will be fit for its purpose and will be as safe as an exis ng la ce structure. In developing the T-Pylon with BYSTRUP from the ini al concept, we have worked through a lot of difficult challenges quickly. Together, Na onal Grid and BYSTRUP have scru nised constructability and maintainability issues ensuring that all health and safety requirements are met. For more info: www.na onalgridt-talk.com
Prototypes of the T-pylon have been produced to analyse the visual impact and for mecanical testing.
- Edward Davey, Secretary of State for Energy and Climate Change, UK.
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To see T-Pylon becoming a reality just 20 months a er winning the compe on, is a fantas c achievement for BYSTRUP and Na onal Grid.
Watch Na onal Grid´s film of the T-Pylon development process. 31
An example of polished stainless steel blending in with the surroundings.
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THE SKY PYLON The Sky Pylon is literally a cu ngedge design structure composed of flat geometrical surfaces.
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To make the Sky Pylon as small as possible, focus has been on height, width, materials and overall costs.
Friederike Faller, Senior Development Designer, BYSTRUP.
Clad in mirror-polished stainless steel, the structure reflects and blends in with the ever changing light from the sky and the surrounding landscape.
Analysis of the standard safety requirements in 2D and 3D projec ons, have lead us to reduce the distance between phases making it possible to create a pylon, where all phases are suspended - in the same horizontal plane. The ps of the pylon carry the earthwires.
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The core of the pylon is built of high tension steel. The reflec ng surfaces are made of plates of stainless steel bent into shape and mounted on the main structure. Stainless steel is available with a wide range of proper es, from standard cold rolled varie es that reflect the light in a beau fully subtle way, to highly polished ones that literally mirror the surroundings.
Stainless Steel will not corrode, get rusty or stained. It is a material that needs very little maintenance.
From the left: Rahul Mehrotra, Peter Rich, Sir Michael Hopkins, Glenn Murcutt, Erik Bystrup and Thomas Herzog in a panel discussion on sustainable architecture in Ferrara. The participants are all members off an international think tank on sustainable architecture.
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WORLD LEADING
SUSTAINABILITY MEANS ACTING RESPONSIBLY Everybody talks about sustainability, while the increasing consumpƟon could have severe consequences for our planet.
This cannot be done through coercion, prohibi on or new laws, but rather by offering quali es that improve everyday life and provide the courage to take responsibility for the future.
Adding the adjec ve ‘sustainable’ to everything will not solve the problem.
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For many years, BYSTRUP has worked with sustainability - or responsible design as we prefer to call it - in order to understand its basic principles. The answer to the problem is a combina on of material characteris cs, thorough knowledge and responsible recycling. To ensure a future which allows a living standard without pollu on and destruc on of ecosystems, we must make sure that things move in the right direc on. Sustainable living must become a natural part of everyday life.
By thinking globally and ac ng locally, it is possible to create a future worth looking forward to. This way of thinking is one of the main reasons why we always include sustainability in our projects: From solar hea ng of large exhibion buildings to naturally ven lated office buildings and the design and planning of new overhead transmission lines. We look for products that op mise lifespan and minimise surface treatments to ensure that only li le maintenance is required. A lifespan of up to 100 years with low maintenance can be achieved by choosing the right materials for 35
Founder Erik Bystrup is one of the judges at the International Symposium for Responsible Architecture in Ferrara, Italy.
the design. We are developing solu ons, based on recyclable materials. We view it as an important parameter for our common future that responsible accountability becomes an essen al part of our everyday life. For this reason, BYSTRUP par cipates in global collabora ons and green organisa ons. Our goal is that sustainability is no longer something you talk about it’s something you do!
MIRROR WALL
REFLECTING THE ENVIRONMENT The pylon is going to be placed at Heia in Troms as part of Statne ’s planned 420 kV line between Ofoten and Bals ord.
Håkon Borgen, jury chairman, Executive Vice President of Statnett.
The Mirror Wall from the Danish company BYSTRUP won the compeƟƟon to design StatneƩ’s first sculpture pylon.
The Jury’s Assessment: The sculpture pylon measuring 34.5 metres in height and 32.5 metres in width stands as an illustra on of the beau ful landscape at Heia. It is a tes mony to nature being a sensa on in itself at this par cular place. The Mirror Wall will not interfere with the vision of nature, but will serve as a reflec on to the many who come here to hike. Mirror Wall is constructed of a simple steel la ce structure. The framework is covered with panels of reflec ng stainless steel with hidden fi ngs to give the desired reflec on of the landscape.
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The Mirror Wall is new and different, yet in harmony with the environment and the scenic loca on. The Mirror Wall is an innova ve and exci ng proposi on which is both integrated into and stands apart from the landscape. The Mirror Wall is both new and different yet in harmony with the environment and the specific loca on. Old and new is synchronised in a single archaic form; the reflec ng square. For more informa on: www.statne .no
A piece of land art placed in the scenic landscape near Heia, Norway.
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FIND SOLUTIONS
TO MAKE OVERHEAD LINES ACCEPTED BY THE PUBLIC In this regard, there is really no prac cal alterna ve to overhead transmission lines in the foreseeable future – only alterna ves when it comes to how these lines will look.
By Marvin L. Zimmerman, Publisher, INMR.
Society has come to regard electricity as a basic necessity of life – even a birthright – much like clean air or water. Highways and railways have long been regarded as normal components of rural and urban landscapes. Yet most cultures seem unwilling to tolerate the presence of transmission towers in their communi es. Using buried cables is the obvious way around this problem. But, from both a financial and technical perspec ve, this solu on is difficult to implement.
One explana on for public resentment is that transmission towers have for too long been neglected – not that they have been allowed to deteriorate but rather in the sense that they have remained focused almost en rely around the basic but uninspired la ce structure design. While this has proven a very effec ve and durable construc on concept, it is in fact a remnant of a me when cost and func onality were the only parameters dicta ng line design. Now, o en showing their age and lacking any systema c evolu on in appearance, they dominate landscapes the world over with what many would describe as nothing short of ‘visual pollu on’.
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Compared to other infrastructure in our surroundings, there has been compara vely li le effort to adjust transmission structures to blend into the landscapes where they are placed. Li le wonder most people do not want them around. So, what about all the posi ves that electrical power structures represent – from the immense technical progress achieved to the fact that they are the only means to avoid climate change disaster by allowing renewable energy to be incorporated into the grid?
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Should these structures not also reflect the fact that electricity is not simply a modern necessity but also the only hope for a sustainable human presence? Expanding the power grid is no longer only a dream but really the only way forward.
Therefore, electricity supply companies must re-think how they design overhead lines and move beyond the aesthe c and design limita ons that tradi onal la ce towers impose.
The Design Pylon was used on a 400 kV line running through rural farmland.
BYSTRUP first began work in the field of overhead line design in 2001 when the oďŹƒce won a compe on for a new 400 kV power pylon for the local grid operator, Energinet.dk. The resul ng structure came to be referred to as the Design Pylon since appearance was the principal criterion being evaluated. A total of 80 such structures were eventually erected on the Jutland peninsula. According to Erik Bystrup, the principal designer, working with such a technical installa on was not easy, especially without much prior experience. In fact, he notes that several aspects would have
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been done differently given subsequent developments and informa on. Says Bystrup, “The Design Pylon, we feel, was an important start but certainly not the last step in the evolu on toward power structures of the future.” His observa on is all too evident when visi ng the Bystrup offices in Copenhagen, where a broad assortment of 1:50 scale models of different structures, are on display. Some have not been developed much beyond ini al sketches while others are almost ready for produc on, awai ng only a final technical and aesthe c review.
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Essen al in the design process for each, explains Bystrup, was answering the basic ques on: “What do we really expect from a power line structure? Is it only a technical necessity, an object of design excellence or a piece of land art? The best answer, he remarks, lies somewhere in the middle of all three requirements. One of the
challenges of any line planner is to op mize the design to meet requirements for mechanical and electrical performance as well as durability.
structure design and conductor configura on was closely examined as this structure was being developed as part of a three level design process.
Clearly, such a technically demanding item needs to be much more than something that is only pleasing to the eye. Moreover, since technical challenges o en vary with voltage, a new design approach may need to be made whenever voltage levels change.
Alterna ves were then thoroughly examined before a final decision was made to erect the design regarded as op mal for that par cular landscape.
Similarly, it is also important to take the configura on of conductors into account. Conductors have a significant visual presence as a transmission line moves across the landscape. This makes them as important to consider in the design of their support structures. Indeed, conductor layout was examined in the Eagle Pylon Project – a twin circuit 400 kV structure recently developed for Energinet.dk. A total of 480 of these structures are erected in Denmark. The rela onship between
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Another important aspect of transmission structure design is choice of construc on materials. Bystrup and his team have begun working with polished stainless steel that reflects the surroundings and makes structures less visible. One concrete outcome was the mirror polished Sky Pylon that was developed as a design alternave to the Eagle Pylon ul mately selected for the Danish line. Apart from mirrored stainless steel, another group of materials being examined by Bystrup are fibre composites whose intrinsic insula ng proper es open radical new possibili es in power structure design.
Such a structure can even be designed without tradi onal insulator strings since the structure itself effec vely acts as the insulator. This means structures that further minimize visual impact. The right use of fibre composites can even help compress structures and minimize a line’s height, subject to mee ng ground clearance and electric field requirements. Each of the tower designs discussed above illustrate that there are not only challenges but also many real opportuni es when it comes to expanding the power grid without strident opposi on by the affected communi es. But to realize these opportuni es, line designers will have to go beyond their ‘comfort zone’ of relying only on the standard la ce tower concept of the past. For more informa on: www.inmr.com
The Eagle Pylon placed in the Danish landscape.
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THE ENERGIEWENDE
By Gerald Reid, Founding Partner, Alexa Capital.
The Energiewende is a term Germany uses to describe the greatest changes going on in its energy markets in over fiŌy years. It is mo vated by a deep-rooted environmental movement within the country as well as increasing concerns about energy security and par cularly the dependence on Russia for gas.
There are five major parts to the Energiewende: 1. The push to renewables. In 2000, Germany produced 6.4% of its power from renewables. In the first half of 2014, this was 28.5% and the country had 84GW of renewable power capacity up from 4.1GW in 1990. This however is only the beginning. The German government intends to generate 50% of its power needs from renewables by 2030. 2. Decoupling of energy and economic growth. Most of today’s u lity regula on assumes economic growth requires energy growth. However, there is now unarguably clear evidence of a decoupling of the rela onship between economic growth and expansion of our energy genera on infrastructure, and this fits in with the German government goal of reducing energy consump on by 20% by 2020.
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3. Digitalisa on of energy. Decades worth of efficiency technology development is now showing significant cost savings across transport, industrial, business and home markets. Consumers are engaging with energy in a way they have never done before, thanks in part to advances driven by the relentless pace of the 1+ billion global smartphone market plus pervasive internet connec vity. Smart grid networks are enabling ac ve pricing of electricity based on supply & demand, real- me. 4. Democra sa on of energy. Power genera on technology advances are delivering compe ve efficiency for distributed small-scale genera on. Germany which over the past two decades has moved from 150 centralized power sta ons to nearly 2 million decentralized power sta ons, has built a society with a leading energy consciousness around new
energy and efficiency with consumer ownership of nearly 50% of renewable capacity.
Donau lattice pylon, remnants of our high carbon past. New energy calls for new grid design.
5. Dealing with intermi ency. Renewable power is o en cri cised that it cannot provide baseload power opera ng 24/7. The sun does not shine at night and the wind does not blow all day long. Intermi ency requires not only a smarter grid than we currently have, but also more high-voltage grid connec ons, parcularly interconnectors between different countries. What does this all mean….we are in for big changes ahead. On the one side, the business models of u li es and their suppliers will con nue to be under pressure. On the other hand, crea ve destrucon will ensure that new ideas and business model will succeed.
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It is going to be an exci ng place to be, especially in an industry where the names, the ways of doing things, the design, and the technologies have not changed much in a century!
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THE COMPOSITE PYLON SIGNIFICANTLY SMALLER
transmission line industry: A pylon rising from the ground as a unibody insulator with two crossarms, each carrying 400 kV. The pylon is made of composite materials that have been in use for 25-30 years in the insula on industry - hence the name Composite Pylon. By Brian Endahl, Senior Development Manager, BYSTRUP.
The design of a future power line should not focus solely on the bits and pieces, but account for all aspects financial, technical, aestheƟc and environmental. A er years of developing power pylons, it is evident that a fresh mindset, as well as a novel approach to materials is needed. We have developed a new pylon that defines a new era for the
The Composite Pylon: - Compact design - Simple and fast foundaƟon - Erected in a day - Standard composite materials - A unibody insulator - Cost compeƟƟve
It is a glass fibre and polymer structure with its surface covered by silicone sheds between electrical phases. By op mising the length of the span related to the height of the pylon, we are able to reduce the distances between the conductors significantly. The pylon can be assembled on site and erected in a single day. This concept makes the Composite Pylon significantly smaller than a la ce tower- a cost compe ve and highly appreciated pylon.
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The Composite Pylon is lower than the regular lattice tower and carries the same amount of power.
Sebas an Dollerup, Head of Power Lines, Energinet.dk.
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The Composite Pylon completely rethinks the design of overhead lines, making it the power pylon for the future.
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BEFORE AND AFTER
IMPROVING AN EXISTING LINE Existing line: Two lines each carrying 1x400 kV.
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Proposed improvement: One line carrying 2x400 kV. The Composite Pylon is able to carry 2x400 kV in a single line. In many cases, this allows for a single composite line to replace two conventional lines.
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BYSTRUP´s competition proposal for a 1x400 kV line in Iceland, a cable stayed composite pylon.
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COMPOSITE INSULATORS THE FUTURE FOR POWER PYLONS
The loadbearing insulator tubes are made of electrical grade fiberglass, reinforced with epoxy resin using a wet filament winding technique. Con nuous fibers are impregnated in a bath of epoxy resin and then wound at a controlled pre-stress onto the mandrel. By Anders Holmberg, Research and Development ABB AB, Composites.
Composite insulators were first introduced more than 30 years ago, and the use of hollow composite insulators on high voltage apparatuses is now well accepted. Composite insulators are proven in the field and are direct replacements for porcelain insulators used in high voltage applica ons. Increased safety, light weight, superior pollu on, and insula on performance are some of the reasons why customers choose composite insulators.
The composite insulators are tailored according to the requirements of each specific applica on to manage the loads to which the insulators are subjected during their service lives. The housings with the weather sheds are made with high quality, high temperature vulcanised (HTV) silicone rubber to ensure the highest possible durability of sheds, as well as outstanding tracking and erosion resistance. Insulators of the conical type oer great advantages in many applica ons. Cost-eďŹƒcient design with lower weight, reduced wind and ice loads, and less visual impact are just some of benefits.
Composite Insulator in the making.
Precise and defined winding of the fiber onto the mandrel ensures uniform laminates of the highest quality.
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Due to recent developments for Ultra High Voltage applica ons, ABB Composites now can provide very large conical hollow composite insulators which make concepts such as the Composite Pylon realisable.
Supported by The Danish Trade Council.
Selected to parƟcipate in the VITUS program for companies with large internaƟonal growth potenƟal.
Supported by InnovaƟonsFonden - Denmark.
Supported by Denmark’s Export Credit Agency, EKF.
www.powerpylons.com
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WWW.POWERPYLONS.COM