The Role of Wind Power in the Achievement of the European Renewable Energy Targets
Undoubtedly, wind energy can play a major role in achieving the European renew- able energy targets. These roles are, according to the EEA Technical report No 6/2009, the following:
• Leaving aside some environmental, social, and economic considerations, Europe’s raw wind energy potential is huge. Turbine technology projections suggest that it may be equivalent to almost 20 times energy demand potential in 2020;
• Onshore wind energy potential is concentrated in agricultural and industrial
areas of Northwestern Europe. Likewise, the largest offshore potential can be found in the low-depth area in the North Sea, the Baltic Sea, and the Atlantic Ocean, with some local opportunities in areas of the Mediterranean and Black Seas. The deep offshore potential is even larger, but cost means that it is unlikely to contribute in any significant way to the energy mix within the near future;
• Environmental constraints appear to have limited impact on onshore wind
energy potential. When designated areas are excluded, onshore technical poten- tial decreased by just 13.7 % to 39,000 TWh. However, social constraints, par- ticular concerns regarding the visual impact of wind farms, may further limit the onshore wind energy development in the future;
• Environmental and social constraints applied to offshore wind potential have a larger impact. Using only 4 % of the offshore area within 10 km from the coast and accounting for the restrictions imposed by shipping lane, gas and oil platforms, military areas, etc., reduce the potential by more than 90 % (to 2,800 TWh in 2020 and 3,500 in 2030);
• When production costs are compared to the PRIMES baseline average electricity generation cost, the onshore potential for wind decreases to 9,600 TWh in 2020, whereas offshore wind potential decreases to 2,600 TWh.
Despite being a small proportion of the total technical potential, the economically competitive wind energy potential still amounts to more than three times projected demand in 2020. However, high penetration levels of wind power will require major changes to the grid system; that is, at higher penetration levels, additional extensions or upgrades both for the transmission and the distribution grid might be required to avoid congestion of the existing grid. Moreover, power flow needs to be continuously balanced between generation and consumption. The total requirement depends on the applied interconnection, geo- graphical dispersion, and forecasting techniques of wind power. Economically competitive potential figures do not include these aspects and the relevant costs. The fact that the competitive potential even in a relative short-time horizon is much bigger than the electricity demand means that the key need for policy makers should be on facilitating the integration of wind energy into the energy system via research and development. Field testing of integration strategies along with initiatives aimed at making demand more responsive to fluctuations in supply is needed. A higher penetration of electric vehicles could potentially be one such application.
The average power production costs to determine the competitive potential are dependent on the fossil fuel and carbon prices. These will vary depending on developments in the global economy as well as developments in scale and cost of greenhouse gas mitigation efforts. The assumptions used here as deemed rather conservative. Thus, the economically competitive wind potential can be higher than presented. On the other hand, applying a single average production cost disregards the regional price differences among different regions (i.e., availability of hydro in Northern Europe) and its impact on the electricity price.
Wind cannot be analyzed in isolation from the other parts of the electricity system, and all systems differ. The size and the inherent flexibility of the power The Role of Wind Power in the Achievement of the European Renewable Energy Targets Undoubtedly, wind energy can play a major role in achieving the European renew- able energy targets. These roles are, according to the EEA Technical report No 6/2009, the following:
• Leaving aside some environmental, social, and economic considerations, Europe’s raw wind energy potential is huge. Turbine technology projections suggest that it may be equivalent to almost 20 times energy demand potential in 2020;
• Onshore wind energy potential is concentrated in agricultural and industrial areas of Northwestern Europe. Likewise, the largest offshore potential can be found in the low-depth area in the North Sea, the Baltic Sea, and the Atlantic Ocean, with some local opportunities in areas of the Mediterranean and Black Seas. The deep offshore potential is even larger, but cost means that it is unlikely to contribute in any significant way to the energy mix within the near future;
• Environmental constraints appear to have limited impact on onshore wind energy potential. When designated areas are excluded, onshore technical potential decreased by just 13.7 % to 39,000 TWh. However, social constraints, particular concerns regarding the visual impact of wind farms, may further limit the onshore wind energy development in the future;
• Environmental and social constraints applied to offshore wind potential have a larger impact. Using only 4 % of the offshore area within 10 km from the coast and accounting for the restrictions imposed by shipping lane, gas and oil platforms, military areas, etc., reduce the potential by more than 90 % (to 2,800 TWh in 2020 and 3,500 in 2030);
• When production costs are compared to the PRIMES baseline average electricity generation cost, the onshore potential for wind decreases to 9,600 TWh in 2020, whereas offshore wind potential decreases to 2,600 TWh.
Despite being a small proportion of the total technical potential, the economically competitive wind energy potential still amounts to more than three times projected demand in 2020. However, high penetration levels of wind power will require major changes to the grid system; that is, at higher penetration levels, additional extensions or upgrades both for the transmission and the distribution grid might be required to avoid congestion of the existing grid. Moreover, power flow needs to be continuously balanced between generation and consumption. The total requirement depends on the applied interconnection, geo- graphical dispersion, and forecasting techniques of wind power. Economically competitive potential figures do not include these aspects and the relevant costs. The fact that the competitive potential even in a relative short-time horizon is much bigger than the electricity demand means that the key need for policy makers should be on facilitating the integration of wind energy into the energy system via research and development. Field testing of integration strategies along with initiatives aimed at making demand more responsive to fluctuations in supply is needed. A higher penetration of electric vehicles could potentially be one such application.
The average power production costs to determine the competitive potential are dependent on the fossil fuel and carbon prices. These will vary depending on developments in the global economy as well as developments in scale and cost of greenhouse gas mitigation efforts. The assumptions used here as deemed rather conservative. Thus, the economically competitive wind potential can be higher than presented. On the other hand, applying a single average production cost disregards the regional price differences among different regions (i.e., availability of hydro in Northern Europe) and its impact on the electricity price.
Wind cannot be analyzed in isolation from the other parts of the electricity system, and all systems differ. The size and the inherent flexibility of the power system are crucial for determining whether the system can accommodate a large amount of wind power. The role of a variable power source like wind energy needs to be considered as one aspect of a variable supply and demand in the electricity system.
The variability of the wind energy resource should only be considered in the context of the power system, rather than in the context of an individual wind farm or turbine. The wind does not blow continuously, yet there is little overall impact if the wind stops blowing in one particular place, as it will always blow somewhere else. Thus, wind can be harnessed to provide reliable electricity even though the wind is not available 100 % of the time at one particular site. In terms of overall power supply, it is largely unimportant what happens when the wind stops blowing at a single wind turbine or wind farm site (Table 5.1).
Because the wind resource is variable, this is sometimes used to argue that wind energy per se is not reliable as an energy source. In this regard, it is important to highlight that no power plant or energy source supply type is totally reli- able—all system assets could fail at some point. In fact, large power plants that go off-line do so instantaneously, whether by accident, by nature, or by planned shutdowns, causing loss of power and an immediate contingency requirement. For thermal generating power plants, the loss due to unplanned outages represents on average 6 % of their energy generation. When a fossil or nuclear power plant trips off the system unexpectedly, it happens instantly and with capacities of up to 1,000 MW. Power systems have always had to deal with these sudden output variations as well as variable demand. The procedures put in place to tackle these issues can be applied to deal with variations in wind power production as well, and indeed, they already are used for this in some countries. By contrast, wind energy does not suddenly trip off the system. Variations in wind energy are smoother,
because there are hundreds or thousands of units rather than a few large power plants, making it easier for the system operator to predict and manage changes in supply as they appear within the overall system. The system will not notice when a 2-MW wind turbine shuts down. It will have to respond to the shutdown of a 500- MW coal-fired power plant or a 1,000-MW nuclear plant instantly.
According to EWEA sources, the capacity of the European power systems to absorb significant amounts of wind power is determined more by economics and regulatory frameworks than by technical or practical constraints. Larger-scale penetration of wind power faces barriers not because of the wind’s variability, but because of inadequate infrastructure and interconnection coupled with electric- ity markets where competition is neither effective nor fair, with new technologies threatening traditional ways of thinking and doing. Already today, it is generally considered that wind energy can meet up to 20 % of electricity demand on a large electricity network without posing any serious technical or practical problems.
EWEA maintains the target it set in 2003 of 180 GW by 2020, including 35 GW offshore in its reference scenario. That would require the installation of 123.5 GW of wind power capacity, including 34 GW offshore, in the period from 2008 to 2020; 16.4 GW of capacity is expected to be replaced in the period. The 180 GW would produce 477 TWh of electricity in 2020, equal to between 11.6 and 14.3 % of EU electricity consumption, depending on the development in demand for power. A total of 28 % of the wind energy would be produced offshore in 2020.
Between 2011 and 2020, the annual onshore market for wind turbines is expected to grow steadily from around 7 GW per year to around 10 GW per year. The off- shore market is expected to increase from 1.2 GW in 2011 to reach 6.8 GW in 2020. Throughout the period considered, the onshore wind power market exceeds the off- shore market in the EU.
A precondition for reaching the EWEA target of 180 GW is that the upcoming EU Renewable Energy Directive establishes stable and predictable frameworks in the EU member states for investors. Much also depends on the EC’s Communication on Offshore Wind Energy and a subsequent adoption of a European policy for off- shore wind power in the EU.
In order to integrate wind power successfully, a number of issues have to be addressed in the following areas:
• System design and operation (reserve capacities and balance management, short-term forecasting of wind power, demand-side management, storage, and contribution of wind power to system adequacy);
• Grid connection of wind power (grid codes and power quality);
• Network infrastructure issues (congestion management, extensions and rein- forcements, specific issues of offshore, interconnection, and smart grids);
• Electricity market design issues to facilitate wind power integration (power market rules).
The major issues surrounding wind power integration are related to changed approaches in the design and operation of the power system, connection requirements for wind power plants1 to maintain a stable and reliable supply, and extension and upgrade of the electrical transmission and distribution network infrastructure. Equally, institutional and power market barriers to increased wind power penetration need to be addressed and overcome.
It is important to stress the following: Wind power is capable of supplying a share of European electricity demand comparable to, or exceeding, the levels currently being met by conventional technologies such as fossil fuels, nuclear, and large hydropower plants. Such penetration levels, however, would require cooperation among decision makers and stakeholders in the electricity sector in order to make the necessary changes to the European grid infrastructure, which was developed with traditional centralized power in mind. Stakeholders in this process should include the following:
• Wind energy sector: Wind turbine and component manufacturers, project developers, wind farm operators, engineering and consulting companies, research and development institutes, and national associations;
• Power sector: Transmission and distribution system operators and owners,
power producers, energy suppliers, power engineering companies, research and development institutes, and sector associations;
• Regulatory authorities: National and European energy regulation authorities;
• Public authorities and bodies: Energy agencies, ministries, national and regional authorities, European institutions, the Agency for the Cooperation of Energy Regulators, and the European Network of Transmission System Operators for Electricity;
• Users: Industrial and private electricity consumers and energy service providers.