NORDJYLLAND POWER STATION. The world s most efficient coal-fired CHP plant

NORDJYLLAND POWER STATION The world s most efficient coal-fired CHP plant

FROM OLD AALBORG TO NEW EUROPE Welcome to Nordjylland Power Station the world s most efficient coal-fired CHP plant. Nordjylland Power Station is owned by Vattenfall, today Europe s fourth-largest generator of electricity. However, the story of Nordjylland Power Station begins not in the far reaches of today s Europe, but in the humble, old city of Aalborg in northern Jutland. IT BEGAN IN THE DOCTOR S ALLEY The year is 1895. Christian IX is King of Denmark dubbed Europe s father-in-law because his two daughters and four sons all married into the principal royal families of Europe. But that is another story. Our story begins in Doktorens Gyde (Doctor s Alley) in central Aalborg, where some enterprising businesspeople establish a private power station. The light station, as the station is popularly called, chiefly supplies electricity to local tradespeople. With a 20 to 25% increase in customers a year, the power station is a success. However, the influx makes the downtown location impractical. So, the local authority considers building a power station outside the city, choosing a site close to the Liim Fiord between Aalborg and Vejgård. The new municipal power station, called Aalborg Kommunale Elværk, is ready for commissioning in 1909. It supplies electricity not only to Aalborg, but also to large parts of the surrounding region. Growth and vigorous development As demand for electricity steadily rises, the generating facilities are extended several times over the next decades. In its heyday the power station also enlarges its supply area to include much of the Himmerland and Vendsyssel regions. The Thy region is added in the early 1960s when the municipal utility is also converted into a partnership with the name of Nordkraft. But the inhabitants of Vendsyssel naturally want their own power company north of the Liim Fiord. This desire fosters the establishment of the Northern Jutland Electricity Supply (NEFO), which commissions its first plant in 1967. Both NEFO and Nordkraft enjoy strong growth and build new facilities over the following years, but the demand for energy and the urban community grow even faster. The power station built outside the city in 1909 is now situated in central Aalborg. Mergers and internationalisation As the European electricity markets are liberalised in the 1990s, mergers become a common tool for Danish power suppliers. Against this background, and to accomplish the task of building a new power station in northern Jutland, NEFO and Nordkraft merge into Nordjylland Power Station in 1995. In connection with the merger, the parties also agree to give up the downtown Aalborg location and instead turn their eyes to Vendsysselværket at Vester Hassing, which offers far better development opportunities. The wave of mergers continues, nationally and internationally. On 1 January 2000, the power stations in Jutland and on Funen merge into Elsam, which performs so favourably that other energy companies are attracted to the shares allocated to the Jutland-Funen distribution companies at the time of the merger. Thus, on 1 July 2006 Vattenfall acquires almost all of Elsam s wind turbines in Jutland and on Funen as well as two small-scale CHP plants in Hillerød and Elsinore and three big power stations, Amager Power Station, Fyn Power Station and Nordjylland Power Station. 3

A HEFTY GREEN GENERATOR With its 171-metre stack and a building topping 90 metres, Unit 3 is a striking feature in the landscape. As a matter of fact, the vastness of the structure and its high efficiency are salient features of this, the most environment-friendly coal-fired power station in the world. UNIT 3 DRIVES THE STATION Nordjylland Power Station generates electricity and district heat in two separate plants, Unit 2 and Unit 3. Known as the world s most efficient and environment-friendly coal-fired power station, Unit 3 is the primary unit. The original Unit 1 has been scrapped. In addition, Nordjylland Power Station has a diesel-fired gas turbine plant at its disposal, which can be used to restart coal-fired generating facilities in the event of nationwide power outages. Environmental and economic benefits Compared with older generating facilities, Unit 3 produces much more electricity and district heat on the same amount of fuel. And the more efficiently every kilo of coal is utilised, the less CO 2 is emitted, and the lower the production costs are. In that fashion, Nordjylland Power Station duly considers both the environment and our heating and electricity bills. Efficiency improvements Much has happened during the 22 years between the commissioning of Units 2 and 3. Using roughly the same quantity of coal, electricity production and, in particular, district heating capacity have improved radically. 171-metre stack Take two Statues of Liberty and put them on top of each other. That gives you approximately the same height as the Unit 3 stack. Cast day and night, the stack took 831 hours to complete, with a truck arriving every hour with concrete. Technical specifications Unit 2 Unit 3 Gas turbine Commissioned 1977 1998 1977 Electricity capacity (gross) 305 MW 411 MW 25 MW Max. district heat capacity 42 MJ/s 420 MJ/s Coal consumption at full load 105 t/h 118 t/h Steam pressure 198 bars 289 bars Steam temperature 535 C 582 C 4

FROM COAL TO ELECTRICITY AND DISTRICT HEAT The duty of a power station like Nordjylland Power Station is to convert the energy of the fuel into electricity and district heat for consumers. Nordjylland Power Station is fired by coal, and up to as much as 91% of the energy content of the coal is utilised. That is a world record that remains unbeaten. COAL ON THE BOILER Conveyors transport coal from the coal site into the big silos (1). From here it is fed to four pulverisers or mills that crush the coal to fine dust. A mixture of air and coal dust is blown up to the 16 burners in Unit 3. Combustion takes place in the boiler furnace (2) at a temperature of 1600-1800 C. The walls of the 70-metre-high boiler consist of endless tubing, through which demineralised water flows and is heated to create overheated steam, which makes the big turbine blades rotate vigorously. Hence, the actual generating facility is an about 50-metre-long turbine group (3), where the energy in the coal in the form of steam is converted into electricity and district heat. Cogeneration of electricity and district heat From the high-pressure turbine, the steam is passed back to the boiler for reheating before it continues through the medium and low-pressure parts of the turbine. The electricityproducing generator (3A) is fitted to the turbine axle. Cogeneration of electricity and district heat ensures optimum fuel utilisation. After the medium pressure part of the turbine, steam is tapped and led through two district heat exchangers (4), where the water from the city grid is heated to 80-90 C. Most of the district heat passes through big pipes under the Liim Fiord to Aalborg. This dispels the commonly held belief that district heat is a waste product. Steam for heating the district heat water is tapped from the medium pressure part of the turbine at a time when the steam would still be able to generate electricity. To optimise operations, an additional 25,000 m 3 district heat accumulation tank (8) is connected to the system. This enables the power station to stop district heat production temporarily and use all the steam for electricity generation instead. End of cycle Finally, the steam not used for district heat production is pumped through a condenser (7), where it is condensed back into liquid form and returned to the boiler for another heating process. This is a closed cycle. The steam is cooled with water from the Liim Fiord. Once cleaned (see next page), the flue gas is emitted through the 171-metre-tall stack (6). 6 Kul 1 2 4 7 3 8 3A 7

COAL-FIRING WITH A CLEAN CONSCIENCE Coal is a fossil fuel formed as plant fibres decompose, a process lasting 80-100 million years. What is more, coal is the most plentiful fuel around the globe, with reserves sufficiently large to cover the world s consumption for the next 200 to 300 years. But coal requires significant environmental awareness at all stages from unloading via stockpiling to combustion in the boilers. WORLD CHAMPION IN EFFICIENCY Nordjylland Power Station burns about 800,000 tonnes of coal annually, primarily brought to the power station on coal barges. Before stockpiling, the coal is cleaned of foreign matter, and big pieces of coal are crushed. Conveyor belts carry the coal from the coal site to the silos at Units 2 and 3. Oil is basically used only for starting up the plants, so annual oil consumption hovers at a mere 9,000 tonnes. When commissioned in 1998, Unit 3 could call itself the world s most efficient coal-fired power station and the title still holds. This unchallenged position is rooted in the strong cooperation that suppliers enjoy with the power station engineers who designed the plant. Cogeneration of electricity and district heat also offers total fuel utilisation of as much as 91% of the energy burnt in the boiler. The high fuel utilisation efficiency means less waste and, therefore, less pollution. Creative reuse In 1992 Nordjylland Power Station was awarded the international McGraw-Hills Prize in recognition of the world s first SNOX plant. It cleans the flue gas of sulphur dioxide and nitrogen oxides and was built for Unit 2. A residual product from this cleaning process, almost pure sulphuric acid, is sold to the fertiliser industry, among others. Unit 3 is equipped not only with an electro filter for collecting flyash, but also with an efficient desulphurisation plant. Suspended limestone supplied by the Aalborg Portland cement factory is used for desulphurisation. The gypsum derived from this process is then returned to Portland for use in the factory s cement production. The flyash is also used in the cement and concrete industry. Hence, Nordjylland Power Station manifests its consistent focus on the environment in its creative reuse policy of utilising residual products from operations as raw materials in other industrial contexts. In brief: An industrial symbiosis with environmental and economic benefits. Read more about Vattenfall s environmental initiatives at www.vattenfall.dk. 8

THE HUMAN FACTOR Seen against the immense dimensions and production volumes of Nordjylland Power Station, the number of employees is relatively small. On the other hand, each employee has a varied and challenging working day. Nordjylland Power Station is therefore a workplace committed to responsible and enterprising employees. KEY EMPLOYEES IN CORE BUSINESSES Nordjylland Power Station s core business, i.e. generation of electricity and district heat, is handled by a permanent staff of talented marine engineers, masters and bachelors in engineering, semi-skilled workers, laboratory technicians, craftsmen and administrative personnel. Great emphasis is attached to hiring the right employees for the various responsibilities and offering ongoing training and development. Competent and ambitious employees are an absolute must in securing Nordjylland Power Station a strong position in the increasingly competitive energy market. Ever-changing production conditions, on the other hand, have necessitated greater flexibility in secondary fields of work. Nordjylland Power Station has achieved this flexibility by outsourcing and contracting out a range of services. Working groups with co-determination Nordjylland Power Station is organised around working groups that involve each employee in several tasks and projects at the same time. This organisation, coupled with shorter communication routes between management and employees, has streamlined the individual procedures and routines. The working groups typically comprise between 9 and 14 employees. Today these groups function as close-knit units that quickly and independently deal with day-to-day operation, repair and maintenance tasks. Organising the work this way moves responsibility and management closer to the individual employee. It gives the individual employee a wider range of administrative duties, but also offers more contacts and better knowledge of other specialist areas. Some of the results are a more varied working day and greater financial awareness. Environment includes health and safety Nordjylland Power Station has achieved OHSAS 18001 occupational health and safety certification and ISO 14001 environmental certification, proving that its management systems meet the requirements of these international standards. The certifications have increased our awareness of the local community, and we have set objectives for continuing to improve environment, health and safety conditions. 11

NEW STRENGTH TO DANISH ENERGY Vattenfall is a relatively new player in the Danish market for heat and electricity generation. In addition to Nordjylland Power Station, we own and operate Amager Power Station, Fyn Power Station as well as small-scale CHP plants in Hillerød and Elsinore and a host of wind turbines in Jutland and on Funen. In spite of our short period of operation in Denmark, we have already invested DKK 2.6 billion in a broad spectrum of innovative projects, including multifuel plants at Amager Power Station and denox plants and a straw-fired plant at Fyn Power Station. In all their diversity, these projects also share a common feature: The improved environmental impact on Danish heat and electricity generation. A MAJOR EUROPEAN PLAYER Vattenfall is Europe s fourth-largest generator of electricity, operating in Sweden, Finland, Germany, Poland and now also Denmark. We are active at all stages of the electricity value chain. That means generation, transmission, distribution and sale. Vattenfall also generates, distributes and sells heat and energy-related services. The Vattenfall group employs more than 35,000 people, and the parent company, Vattenfall AB, is wholly owned by the Swedish state. Vattenfall in Denmark is part of Business Group Vattenfall Nordic, which counts about 9,000 employees in Sweden, Finland and Denmark. The number of employees working in Denmark is about 650. The Danish organisation was established in mid-2006 when Vattenfall acquired both employees and generating facilities from DONG. Two regional offices have been set up in Denmark, one in Copenhagen and one in Fredericia. A visionary company Vattenfall s vision is to enhance our customers competitiveness, environment and quality of life through efficient energy solutions and world-class service. This vision is met through five strategic ambitions for our initiatives: Vattenfall wants to: ensure continued profitable growth be the benchmark of the industry be Number One for the customer be Number One for the environment be the employer of choice To realise our ambitions and vision, Vattenfall invests in new generating facilities, modernisations and efficiency improvements at existing plants, improved environmental performance, effective maintenance and enhanced safety. Vattenfall additionally invests in competencies and new knowledge. Everything for the benefit of our common future. 12

STABLE SUPPLY AND EXCITING WORKPLACE Nordjylland Power Station the world s most efficient coal-fired CHP plant I fully agree! From the outset, Vattenfall s decision to acquire Nordjylland Power Station has been both exciting and right for us. Not only did we succeed in ensuring a stable and solid supply of heat and electricity to northern Jutland households the acquisition also enabled us to maintain a good and exciting workplace. And that s essential when you choose to sell one of your assets to a relatively unknown undertaking. much speculation, and I guess no one fully knows how the sector will look in a few years time. One thing is certain, though: In Aalborg we are extremely satisfied that Vattenfall became responsible for forging the path to a safe future for Nordjylland Power Station and I m confident that the employees at the power station share my thoughts. Today Vattenfall is no longer unknown to us, however, and we keenly look forward to seeing how the group s planned massive investments in Denmark are going to affect northern Jutland. The outlook for the energy sector is currently the subject of Henning G. Jensen Mayor City of Aalborg 15

Vattenfall A/S Generation Nordic, Thermal Power Nordjylland Power Station Nefovej 50 9310 Vodskov Tel. +45 88 27 50 00