http://www.juventudrebelde.cu/suplementos/en-red/2012-04-28/son-molinos-podrian-ser-gigantes/ Are those windmills? They could be giants! . Cuba’s wind energy program could take off with the help of eight new sites capable of producing a total of 280 MW. Such an investment would yield net savings, but the potential profit depends entirely on the experience gained from the four wind farms already in operation. Several Authors / April 28, 2012 - 20:45:28 CDT We must zealously evaluate the operational output of our four wind farms before we spread the use of this natural energy reserve and –given our financial limitations– pay good heed to the cost-benefit, going through every investment in this field with a fine-tooth comb. Such is the approach that must prevail in our studies to deploy, before 2020, eight new wind farms with a total power of 280 MW, a step involving a significant outlay but one likely to be recouped in less than ten years, according to Emergent Generators and Renewable Energy Sources (GEEFER) director Aleisly Valdés Viera, thanks to yearly savings worth more than 216,000 tons of fuel otherwise spent to produce electric power using conventional technologies. To get an idea of the leap forward this investment entails, suffice it to say that all four wind farms currently in use produce only 11.70 MW. In light of this economic outlook, to be supplemented with other profits, we must also put on the table the effectiveness of our investments and every assessment of the conditions required to secure the proper yield and sustainability of these projects, as well as the lessons learned from the implementation of these projects in several provinces. From Turiguanó to Los Canarreos This technology was first put into practice in Cuba in the late 1990s, when “two big windmills” changed the landscape in Ciego de Ávila province’s Isle of Turiguanó. Opened on April 21, 1999 to service around 2,248 people in several surrounding settlements with a small potential of 0.45 MW, this pilot park was Cuba’s first try at this kind of renewable energy. As stated in Cubasolar’s website, its two medium-voltage environmentally-friendly system of wind turbines are connected to the National Grid. The initiative kept spreading, and a program was launched in 2005 to set up more wind farms following a process of nationwide wind-speed measurements at various heights to pinpoint the best sites and studies of the relevant state of the art and worldwide trends in the use of wind power, all of which began to bear fruit with the experimental wind park Los Canarreos, in the Isle of Youth, fitted with six turbines made by the French company Vergnet. “A common feature of these wind-driven generators is that they can be taken apart, remarked local GEEFER director Juan Carlos Granela, so in case of a hurricane warning the towers holding the rotor blades can be taken down within the hour for safety’s sake. Its location right in the middle of the path followed by the trade winds and the fact that it has steady, high lands and a valley were the reason that the Isle of Youth was chosen for this purpose,” he added. “In five years –it was opened on February 24, 2007 with a capacity of 1.65 MW– Los Canarreos have meant savings of 1,428 tons of fuel and almost 139,481 dollars.” Operation and Maintenance boss Luis Morales hails the experience gained in the organization and planning of this kind of investment, the qualification of specialists, and the connection of a wind park to the power supply system as the project’s most valuable outcome. Four employees –two mechanics and two electricians– take care of the remote-controlled windmills and their regular service. “However,” says Morales, “since this is automated, software-operated equipment, they must get training on and be ready to carry out maintenance work”. Cubasolar experts point out how much they have learned in terms of prevention in face of difficult weather conditions and mitigation of their effects. “Even if we chose particularly storm-resistant technology, in 2008 Hurricane Gustav damaged two blades,” Morales recalls. “The main risk is the chance that they’re struck by lightning. Never mind that Vergnet fitted the power lines with surge protectors and lightning rods, when those mean bastards fall down they stop at nothing”. These mills ‘read’ the winds and start working at their lowest when they blow at 4 m/sec, while their sensors define their direction and align the blades automatically to make the most of energy. “In my experience all along these five years, generation is highest in autumn and winter and less efficient in July and August.” High on the list of benefits provided by Los Canarreos, according to the workers, is its capacity to feed the towns of La Reforma and Juan Delio Chacón, but this is not the best benchmark, because both are small settlements with no industries. It’s not La Mancha, but Gibara Nor is this a place the name of which people would rather forget, much as the landscape reminds of La Mancha. We are in the municipality of Gibara, near Holguin province’s northern coast, where two new wind parks were built –Gibara I in 2008 (5.1 MW) and Gibara II in 2010 (4.5 MW)– to turn the local strong winds into clean energy. Looking back over the life of both projects brings to mind the most extreme situation the staff and especially the first park’s facilities have ever been exposed to: the devastating effects of Hurricane Ike in 2008, amazingly “timing” in that it hit the premises barely a few months after the six wind turbines of Spanish technology had come into operation. Gibara’s Wind Power Generation unit director José Luis Pifferrer still remembers that at first Ike’s impact was not as noticeable in the towers as it was in Gibara I’s control room and its substructure, a single-level building less with aluminum and glass windows and doors located less than a hundred meters from the sea. Of the six towers in this site, the closest one to the shore was built at a distance of 60 meters. Rolando Gómez Gómez, a young mechanical engineer, mentions that they have 11 employees on the payroll –five engineers, four middle-level technicians and two skilled workers– whose average is below 35 and all of whom made the most of the knowledge passed on to them by foreign specialists both before and during construction, although every worker was aware their skills would eventually be put to the test by other challenges, for instance, corrosion. Indeed, the effects of sea salt residues became obvious first on the metallic structures and the towers holding the wind turbines, and some time later on their electrical and electronic systems. “Our lifelong partnership with sea salt here in the park has forced us to redefine our maintenance protocols and come up with methods that not even the manufacturers have ever foreseen, starting with basic solutions like applying anticorrosive paint on the outside walls of the towers,” Pifferrer underscores. “We have made filters for the windows and access doors,” he adds, and the results are plain to see in the way we have curbed rusting.” Gibara II, a project that took due heed of the proper distance from the sea, stands as the best evidence of the staff’s know-how and can-do. Even the control room was placed 400 meters from the seashore and at a higher altitude above sea level, which makes it unreachable by any groundswell. The second floor houses the operating and control systems for the wind turbines –made in China– and the doors to each tower are higher from the ground than Gibara I’s. Worthy of mention among the contributions made by the staff is the development by the young Automation engineer Sandro Claro Díaz of what he tagged Integrated Operational System for Wind-Driven Power Generation, a software that registers statistical data on performance. “We realized right from the outset that we had nothing to record the huge volume of information produced by a wind park that can be used for future reference,” says Sandro. “This tool makes it possible now to have statistical control and an early-warning system for faults and what caused them.” But they also learned other lessons. As Pifferrer said, in the beginning they didn’t have all the required gear either, “so we had to devise many of our own maintenance tools and spare parts.” Some manufacturers hold that as a rule this technology has a useful life of 20 years, but at the end of the day the final figure is contingent on a variety of factors, including the behavior of the winds. The director of both Gibara parks thinks that even if we are still new to wind power generation everyone is convinced of its good prospects, which call for further emphasis on regular training and qualification opportunities and the provision of spaces to exchange views, taking into account that this is an expensive and fast-growing technology. On the road to 2020 A review of the use of wind power in Cuba reveals that the northern part of the island, from Villa Clara to Guantánamo, provides the best locations. Therefore, sites were screened on the basis of a national wind atlas and some feasibility studies to assess the possibility of deploying eight new parks before 2020 –six with a capacity of 30 MW and two with 50 MW– in various provinces. About these plans, GEEFER director Aleisly Valdés Viera also said that the first four experimental parks showed to be flawed enough to hamper production, technical availability and operational reliability and, consequently, more expensive to maintain and operate. Typical as they are of a process to assimilate a new technology, these shortcomings compel such corrective actions before the next stage as a sound technical and marketing process to contract for future parks better quality requirements, and a procedure to check their fulfillment, as well as ways to find all the relevant design information to verify the technical condition of every component and spare part and the right blueprints with specified maintenance guidelines. It’s no less imperative to extend the manufacturer’s supervision period, purchase the necessary fault-predicting means, and organize the all-embracing qualification of technicians, engineers, operators and supervisors. Valdés Viera also stresses the need for both intense technical training courses from the very outset with the help of the hired entities and the participation in the start-up process of the abovementioned members of the staff. Furthermore, all timetables must be strictly respected and every possible scenario and variable analyzed in order to recover the investment in due time. “If we expect to be successful,” he warns, “we must work hand in hand with our industry to decide what parts can be made here and plan for the proper transportation and hoisting equipment. “Not only would Cuba’s commitment to this alternative have economic fallout (the average generation cost of wind power is 3 cents per kW, whereas that of conventional generation is 27 cents), but every year these giant towers would save us from giving off to the atmosphere 184,000 tons of carbon dioxide and other greenhouse gases. And yet, we can only meet such a goal if we bear in mind the lessons learned from the four wind parks we have today.