jiangsu rudong 150mw intertidal demonstration wind farm
longyuan zhenhua large marine construction ship
100 million and 10 million, these two figures are significant to each staff of china guodian corporation. by the end of oct. 2011, the total installed capacity of the corporation had surpassed 1 billion mw, among which the installed capacity of wind power was more than 10000mw and whose symbolic wind turbine was located in jiangsu rudong 150mw large offshore (intertidal) demonstration wind farm. guided by the strategy of “greatly developing new energies and leading enterprise transformation", the corporation has made prominent achievements in the development of offshore wind power.
compared with onshore wind power, offshore wind power is still at the stage of exploration. among the 10000mw installed capacity, offshore wind power only occupies a small proportion. however, since the competition of onshore wind power is more violent and the growth has slowed down, it is specially significant to develop offshore wind power. in recent years, guodian longyuan has been active in the practice of exploring the development of offshore wind power and accumulated valuable experience for the development of china guodian corporation and the whole industry.
to overcome many difficulties in order to complete projects according to schedules.
jiangsu rudong 150mw intertidal demonstration wind farm is the first offshore intertidal demonstration wind power project in domestic china. after its completion, the on-grid volume of electricity is about 375000mw/h each year, which can satisfy the normal power demand of 300,000 households. its development and construction plays an active guiding role in the aspects of wind farm concerning evaluation and site selection of wind resources, planning and design, construction, operation and maintenance. in addition, it can lay a solid foundation for the localization of the manufacture of china’s offshore wind power equipment.
by oct. 31, 2011, three operation surfaces had been put into the construction of turbine foundations in longyuan rudong 150mw intertidal demonstration project; the third operation surface of hoisting turbines had started site construction; the basic construction of 34 turbine units and the hoisting of 22 turbine units had been completed. the first 50mw installed capacity had been put into production.
longyuan (jiangsu) offshore wind power co., ltd introduced that they would continue to promote project schedule while ensuring their quality in the remaining two months so as to try to realize 100mw installed capacity by the end of this year. then the installed capacity of the offshore intertidal wind power of china longyuan power would rank first in china and the largest offshore intertidal wind farm in the world would be built. apart from that, they planed to finish the foundation construction of the remaining 3 turbine units and the hoisting of at least 8 turbine units so as to lay a good foundation for the production of the whole project next year.
the excellent performance is backed by the constant contribution and hard work of the young staff of china longyuan power.
it costs 20 days to build the foundation of a turbine unit and concrete foundation while 10 days to build that of multi-pipe pile. in order to improve the efficiency, the company decided to adopt the technology of single piling driving in large scale. as the first one to try tomato, the company didn’t have any advanced experience to be followed. the verticality error of the first two attempts to drive single pile surpassed greatly the industry standard which couldn’t meet the technological demand of the normal operation of turbine units.
at that time, some foreign experts believed that using the present technology, it was impossible to control the error rate below six thousandth. however, after repeated studies and several rounds of discussions carried out by the design institute and experts, the company believed that pile driving was sure to be a success so long as the foundation piles could be adjusted to be vertical under natural condition. therefore, questioned by experts, the company started its third single pile driving.
on aug. 13, the project construction team of longyuan offshore company succeeded in driving the single pile which was 50m long, 5m in diameter and weighed several hundred tons into a place 40m below the ground surface after spending over two hours swinging more than three thousand strikes of impact hammer. finally they restricted the error rate below two thousandth. thus, they had completed the single pile foundation driving that met industrial standard for the first time. it also indicated that the company had grasped the core technology of large-scale development of offshore wind power.
from then on, working day and night, longyuan (jiangsu) offshore company continued to promote project construction based on the law of tide and ebb.
tide and ebb are influenced by the moon and they take place twice a day. the next day it is usually delayed about one hour and one cycle consists of fifteen days. the construction staff shall adjust their timetable according to the level of tide and ebb because they have to transport via the vessel in the tide and settle it on the beach in the ebb. this work mode is vividly called as “follow the moon” by the staff of china longyuan power.
the work time has been separated into shorter periods and the effective time is very short and broken into pieces because of the huge body of the vessel, slow movement as well as the continuous change of tide and ebb. therefore, the work chains should link with each closely and each minute counts. it's possible that the project progress might be delayed one day merely because of one minute error and they have to wait for another level of tide and ebb. these factors determine that the staff on the ship cannot land frequently. so the construction vessel becomes their second home.
in order to ensure the project schedule, the construction staff of the company has to stay long on the vessel. their only hope is to accelerate project schedule on condition that safety and quality can be guaranteed so that the 150mw intertidal large demonstration project could be put into production as soon as possible while maintaining and expanding the leading position of the company in the industry of offshore wind power.
to march forward with pioneering spirit so as to accumulate experience.
china longyuan power only took 4 months to complete the hoisting of 22 turbine units since the initiation of the 150mw intertidal large demonstration wind farm on june 21. however, it was not done at one stroke. in fact, as the first one to try tomato, the company has experienced exploration and accumulation for a long time.
in june 2009, the construction of 32mw jiangsu rudong intertidal test wind farm started. this project is the first offshore wind power project developed by china longyuan power. at that time, it became the focus of the whole industry and its result was crucial for china to open the door of offshore wind power.
then the company had neither such large construction ship, nor any experience to be followed. the construction staff had to go to sea almost each day in the hope of grasping the hydrological features in the offshore area as soon as possible and find a set of good construction process.
day after day, they travelled between the land and the intertidal area. they came to the beach and investigated its surface. finally they settled the route of marine cables, construction plan and the shipment plan of the main equipment of wind turbines. in the end, the company grasped the first set of construction process of intertidal wind power and found the approach to the construction of offshore wind power which was suitable for the hydrological, geological and coastal features in the coastal regions of china. on sept. 28, 2010, the test wind farm project was completed, which was a zero breakthrough for the offshore intertidal wind farm across the world.
since it was put into production, the test sampling turbines has run smoothly. from the grid connection of the first turbine units on oct. 20, 2009 to the end of august 2011, the accumulated generation of electricity was approximately more than 83000mw/h. in its normal condition, the generation of the wind farm can reach 80000mw/h. its utilized hour was over 2500 hours and the utilized rate of equipment was beyond 93%.
in the construction of the 32mw intertidal test wind farm, the company explored and accumulated rich management experience of offshore wind power as well as trained a staff team which was united and brave to challenge difficulties so that the company had laid a solid foundation for large-scale development of offshore wind power in the future.
on oct. 8, 2010, the company succeeded in winning the tender of the chartered 200mw wind power project of jiangsu dafeng intertidal wind farm. therefore it continued to strive for a higher goal.
to build brand through technological innovation.
in aug. 2011, the company’s project of “key technology research of offshore(intertidal) wind farm project” filled the technological vacancy of the development in the field of offshore(intertidal) wind power. it was presented with “the first prize for scientific progress” and “organization prize for scientific progress” by china guodian corporation. in april 2011, jiangsu provincial development and reform commission fully recognized the innovative achievement made by china longyuan power in the development of offshore wind power in domestic china and presented longyuan(jiangsu) offshore wind power co., ltd. with the tile of “2010 advanced unit of energy work in jiangsu province”. prizes and titles won by the company constantly urge it to actively build the brand of offshore wind power and become the whole industry’s benchmark of developing offshore wind power.
the greatest challenge of exploring approaches to the development of offshore wind power is technology. in project development and construction, through continuous exploration and innovation, the company has overcome many technological difficulties, grasped the key technology of developing the wind power in intertidal zones, and found an approach to independent innovation.
the mudflats in intertidal zones are very soft. although the surface of the beach seems “hard”, yet a gentle step on it might let it liquefied into a "paste-like substance". heavy machinery cannot be freely used here. water depth is just a few meters and the conventional construction vessels cannot function well here. after over two years’ study and repeated test, the company established the plan of “transporting equipment via vessels and field shifting of construction vessel in the tide while residing and constructing on the beach in the ebb”. it succeeded in developing the shallow-draft flat-bottom barge which was designed specially for the construction of wind power in intertidal zones and could reside on the beach so that it made it possible to construct projects of wind power in intertidal zones which had been impossible in the past. therefore, it made a breakthrough in the development of wind power in intertidal zones in the world.
the foundation of wind turbines is the key technological difficulty in the construction of intertidal zones. summarizing the experience of onshore wind power construction and learning advanced construction technologies from other countries, the company first adopted the large-scale single pile driving technology and perfected the plan of multi-pile construction. the foundation of wind turbines which is characterized by steel structure, multi-angle, large diameter and single pile was adopted in the construction of rudong 150mw offshore intertidal demonstration wind farm. meanwhile, the company succeeded in driving several single-pipe piles which weighed 400 tons and whose verticality was controlled within the designed standard so that it had improved the construction efficiency of offshore wind power. in multi-pile construction, because the radius of geological exploration point was shorter than the allocation radius of the actual location of construction equipment, the water depth of some pile points was so deep that it had impacted construction schedule. we grasped the movement location of the equipment in time and fix the target. as a result, we avoided the economic loss resulted from the landscape difference below water surface and ensured the quality and safety of foundation construction.
a lot of special equipment is required in the wind power construction of intertidal zones, which influences the cost of wind power in intertidal areas as well as restricts large-scale construction of wind power in intertidal zones. jointly ventured by china longyuan power and shanghai zhenhua heavy industries co., ltd, jiangsu longyuanzhenhua ocean engineering co., ltd. is a professional company dedicated to the construction of offshore wind power. it has purchased s-800 large-sized impact hammer from the dutch ihc. it has made a success in the test of single pile driving and procured over 20 professional vessels including cable layer, anchor handling vessel, hoisting vessel and transport vessel. on may 18, 2011, the first 800-ton revolving derrick barge of offshore wind power was put into use. this barge is specially designed according to the hydrological features of the coastal regions in china. equipped with 800-ton revolving marine crane and s-800 hydraulic pile-driving hammer, it can be widely applied to the constructions in china’s intertidal zones and shallow seas, including marine constructions, such as single pile driving of wind power project and the installation of wind power equipment. at present, it is the professional vessel used in intertidal zones which is most powerful in lifting and pile driving in domestic china. therefore, not only it can reduce the construction cost of offshore wind power by about 25%, but also the company can put 3 marine operation surfaces into work at the same time by using the presently-owned construction equipment.
now the company has possessed several construction patents of offshore wind power, such as “construction equipment of wind power in offshore intertidal zones”, “steel-pipe pile driving equipment”, and “steel-pipe pile driving process”. even the experts who once questioned it have held their thumbs and praised highly their pioneering spirit. depending on its own technological innovation, the company has set up its brand of offshore wind power and pointed out the direction for the whole industry’s development of offshore wind power.
work solidly to make new expansions.
offshore wind power characteristics as follows: it has rich resources, more utilized hours, no land occupation, no water consumption and is fit for large-scale exploration. therefore, in recent years, eu and the us have started to shift the focus of their wind power exploration to offshore wind power. many large wind power development enterprises and equipment manufacturers are actively exploring their approaches to wind power development. by the end of 2010, 43 offshore wind farms had been set up across the world. the total installed capacity had reached 3670mw and the newly installed capacity of last year had singly reached 1440mw.
china is rich in offshore wind power resources and the recoverable volume in the offshore shallow seas is approximately 2 billion mw. in recent years, china has been actively promoting the development of offshore wind power. although its initiation is late than that of european countries, its speed is very fast. at present, it possesses good foundation and conditions both in policy and technology. the state has put forward the target of developing offshore wind power according to which 5000mw installed capacity will be realized by 2015 and 30000mw by 2010.
besides, factors, such as insufficient transmission lines and uneven development in different regions, have become the large bottleneck that restricts the development of onshore wind power. because of the booming economy and strong power digestion ability in china’s coastal areas, there is no problem of assimilative capacity. therefore, it offers convenient conditions for the exploration of offshore wind power. in the future, offshore wind power will become an important field of china’s wind power industry.
it can be seen obviously that the company is dedicated to his strategy of “braving the wind in the sea” rather than follows the trend in european countries and the us. it is an important strategic deployment for the company to develop offshore wind power so that it can accelerate its development, expand its market space in the future, seize commanding height in competition and continue to maintain its leading position in the industry.
on oct. 10, china longyuan power held the preliminary symposium on offshore wind power which was to accelerate its development of offshore wind power in full scale. it also symbolized that the company’s strategy of “greatly developing offshore wind power” had been promoted from jiangsu to china’s provinces rich in wind power resources.
in the future, based on its principle of “working actively and stably, planning comprehensively, developing in good order and reducing cost”as well as accumulating exploration and construction experience, maximizing the cost of offshore wind power and investment risk, the company will gradually develop wind resources in offshore areas so as to provide endless drive to the sustained development of the company.