The use of offshore winds as a source of energy was first applied by the early sailors and explorers who captured it in the sails of their ships, and used it to take them to new areas. According to Schobert (2005), it is offshore wind energy that facilitated the early forms of trade in ivory, spices and slaves. This comes from the fact that these early merchants and trader relied on the monsoon winds to propel them to Africa and back to Arabia and the Caribbean. Of late, the use of offshore wind energy has taken another dimension from facilitating trade and exploration to facilitating the safe and environmental friendly production electricity. This paper discuses offshore wind energy.
Offshore Wind Energy
Lynn (2011) has observed a growing trend of a shift from reliance on hydroelectric power to offshore wind energy among a good number of countries especially European nations where it has been used extensively. She noted that this trend could have been motivated by the increasing demand for power among the developed and developing nations. These nations have erected wind turbines in their ocean bodies to harness this freely available energy source.
Offshore wind energy in the view of Schobert (2005), is created when the offshore winds are turned into power through the use of wind turbines to generate electricity. Wind energy is assumed to be an indirect form of solar energy. This idea probably comes from the belief that one to two percent of the solar radiation that strikes the earth’s surface is converted to wind energy. Actually, wind energy has its source from the disproportionate heating of diverse parts of the earth’s surface. According to Lynn (2011), this unequal heating causes the cooler dense air to circulate to creates wind; a form of energy. Lynn (2011) further explains that even though a portion of the sun’s energy is usually absorbed directly by the air, most of it is first of all absorbed by the surface of the earth. After this absorption it is then transferred to the air by convectional means. From this, we get wind energy.
The Use an the future of Offshore Wind Energy
According to the European Wind Energy Association [EWEA] (2010), Europe has been the largest user of wind energy. It is currently estimated that a considerable portion of its future utilization of wind energy will come from its offshore wind energy sites. Currently, several Europeans countries are in their planning phases of constructing their large offshore wind farms. The economic viability of these offshore wind energy farms depends upon favorable wind condition compared to the onshore farms.
The onshore farms according to EWEA (2010) are challenged by a number of barriers to wind energy. These barriers include unwelcoming neighbors, animal and human rights activist and environmentalists who argue that the wind turbines pose threats. Other arguments are that the wind turbines cause pollution by producing noise, their presence interrupts the beautiful scenery, and they are the cause of death of some birds. Apart from the activists, another challenge is weather. The offshore wind energy source is not very effective during the calm weather.
However, EWEA (2010) notes that with the invention of the offshore farms, this challenge has been overcome. The offshore farms unlike other wind turbines are advantaged given that wind is ever present over the oceanic water bodies. Another benefit the offshore farms have over and above onshore farms is that their higher energy yields comfortably recompenses the extra costs of installation and maintenance of more wind turbines. According to EWEA (2010), the global wind generation market relies on the inconsistent government support subsidies. This support is much in the European nations given the fact that wind energy is their major source of power. The generation of offshore wind energy in the United States remains relatively low at nearly less than one percent of its energy production.
Wind players like the United Kingdom, Germany, Denmark and other European nations, view the long term opportunities and benefits of offshore wind energy as considerably huge. These nations have seen the opportunities in the ocean given that they possess enormous offshore potential. According to the estimates by EWEA (2010) the offshore potential is capable of satisfying Europe’s energy demands by at least seven times. The association estimates that the offshore wind energy deployment is likely to experience a dramatic increase in Europe in a couple of years to come. This expected expansion is mainly driven by the European Union and national policies that are geared at providing much greater penetration of renewable energy supplies.
According to EWEA (2010), the European Union under its European Commission, has set 2030 as a renewable energy target. This target tries to achieve a reliance on offshore wind energy of thirty to forty times by 2020. In addition, it also seeks to achieve a further dependence by one hundred times of the present installed offshore wind energy capacity by 2030. According to EWEA (2010), Europe has over one thousand two hundred and forty seven offshore-installed grid-connected wind turbines. This brings a total of three thousand two hundred and ninety four megawatts of installed capacity across the forty nine wind farms in Europe.
Best Sites for Offshore Wind Energy
Nations relying on offshore wind energy have to choose the areas with the best winds. For example, Lynn (2011) remarks that the narrow channels between islands and headlands, openings to lochs, and large harbors and bays experience high marine current flows. This makes them the best locations to harvest wind energy since they consistently experience high wind currents. Apart from narrow straits, areas where the water depth is slightly shallow and good tidal range exists, also offers the best places to harness wind energy. Additionally, areas that experience wind velocities of up to five knots and above are the best sites for offshore wind farms.
Schobert (2005) has observed that countries like the United Kingdom, Japan, Ireland, the United States and Italy have been endowed with these offshore power favoring resources. The United States for example has the continuous currents moving close to the shore in its areas which have the highest demand for power. These currents include the Gulf Stream and the Florida Current and if this nation could embark on developing wind energy as an electricity source, then these currents are most likely to support this project.
Why Offshore Wind Energy?
Most of the world’s developed nations recognize wind energy as a proven technology appropriate in meeting the increasing electrical energy demands in the most suitable and clean way. Schobert (2005) argues that, offshore wind energy is normally located where there is an increased energy need and demand. EWEA also (2010) notes that with offshore wind energy, environmental concerns like visual impact and noise pollution have been greatly reduced given that they are located far away from human settlements in the seas and oceans. Despite its little negative impact on the environment, there exist some isolated considerations. For example, Schobert (2005) has observed that working offshore could bring about a localized disturbance of the ocean and seabed.
Schobert (2005) has further shown that some of the offshore farm’s foundations act as artificial reefs resulting into an increased fish population from the new supply of food. Somehow the noise from the turbines in the offshore farms travels underwater and disturbs sea life. But on the other hand this noise cannot be presumed to be a threat given that engines, ships and boats have been part of the sea for years.
EWEA (2010) contrary to the environmental concern, sees wind energy as an effective tool for mitigating climate change and as a key technology of de-carbonizing the European power sector. They further claim that wind energy had avoided 126Mt of Carbon dioxide pollution by 2010 and they estimate that by 2020 they will have avoided 342Mt and 646Mt by 2030. In addition deployment of wind energy has reduced Europe’s fuel costs and strengthened its industries by providing more employment opportunities.
According to Lynn (2011), a number of factors which have motivated the development of offshore wind energy industry. Funny enough, offshore wind energy installation is extensive and has higher initial energy costs than its onshore counterparts. So what could motivate the European nations to venture into the wind energy industry and use it as an alternative energy source? May be it is because they no longer want to rely on importing energy, or it could be cheaper. EWEA (2010) argues that the offshore wind industry has contributed significantly to Europe’s competitiveness, leadership and has greatly reduced its dependence on electric energy importation.
Europe has an uninterrupted access to the largest domestic energy resource available which is offshore wind energy. EWEA (2010) says that offshore wind power is very vital for Europe’s future as it provides the answer to its climate and energy dilemma. It creates an opportunity of exploiting the largest and abundant energy resource which does not emit greenhouse gas, reduces the reliance on costly fuel imports, and provides enormous quantities of indigenous affordable electric energy.
Despite the fact that the initial cost of constructing offshore wind farms is high, EWEA (2010) noted that it is cheaper than non-renewable technologies, and has low risks compared to them. The association has further argue in favor of the ‘not in my backyard principle’ in which case most people are not impressed with having the wind turbines in their area. Setting these wind turbines at sea reduces land constraints like planning challenges, visual impact, and the chances of causalities incase wind turbines falls or gets damaged. Other reasons for the preference of offshore wind energy are like the opportunity to implement new technology that it presents improved navigation and fishing issues, and the benefit of the economies of scale derived from the large wind farms.
Challenges Facing Offshore Wind Energy
Notwithstanding the benefits they present, offshore wind energy has a number of challenges. First of all Lynn (2011), cites the rough weather and the fact that the state of the seas may be much rougher than it is on land as a major setback. The rough weather can inhibit the installation of wind turbines, and prevent their frequent monitoring. Besides, installation of offshore wind energy devices is costly and difficult, and its connection costs are unusually greater. Furthermore, the construction costs and the challenges of bringing electricity obtained from offshore energy to the power grid makes off shore wind energy an expensive venture.
Lynn (2011) further argues against the economies of scale benefit since it can only be attained if the offshore wind farms are large enough to shoulder the high initial installation and maintenance costs. Furthermore, the investments and risks associated with offshore wind energy are great than any other renewable energy sourcing. To sum it all up, wind is not predictable this calls for the use of other additional sources of energy to make up for emerging shortfall.
In conclusion, offshore wind energy is a boost to the current energy reserves for the countries that have embraced it. Though it has high initial set up costs, it is an easily available source of energy that Europe is enjoying. Its use dates back from the seventeenth century and it is not going to die soon, given the 2030 and 2050 targets of the European nations.