In recent times, concerns have been raised about the growing number of wind farms in developing countries and their impacts on communities and the environment.
Many of these concerns have been fuelled by well-organised anti-wind groups.
By spreading disinformation about wind energy, these groups have successfully persuaded many people, including several prominent politicians, that wind energy does not have a legitimate role to play in addressing the challenges posed by climate change or energy demands.
The purpose of this article is to assess by questioning the merits of the main arguments used to justify opposition to wind farms, namely: the competitiveness and cost of wind energy; its efficiency and reliability; its ability to reduce greenhouse emissions; fire risk and noise pollution; impacts on biodiversity, landscape and heritage values; and effects on property prices. The evidence indicates that wind farms are a favorable option.
Wind energy is competitive with all other sources of renewable energy. The evidence indicates that if electricity generators were required to internalize the costs of pollution, it would also be competitive with coal- and gas-fired power stations. Economies of scale and technological improvements are likely to continue to improve the efficiency of wind energy, with projections suggesting that wind energy could be competitive with gas- and coal-fired power generation by 2020. Pakistan has made a good start in this direction by the readying the FFCEL 50MW wind farm at Jhimpir.
The displacement of conventional fossil fuel-based generation for wind energy does increase the cost of electricity. However, at current levels of wind penetration, the additional cost to most consumers is negligible. If wind penetration increased substantially, the additional cost to consumers would be more significant, but still only small to moderate depending on the size of the increase in wind energy. The evidence suggests that increasing the proportion of electricity that is obtained from renewable sources from 11 per cent to around 15.5 per cent is likely to result in an insignificant percentage increase in the average household electricity bill. If this occurred, a large proportion of the increase in renewable energy is likely to be sourced from wind.
Wind farms, like all other types of electricity generators, do not operate at 100 per cent capacity 100 per cent of the time. They usually generate between 20 and 40 per cent of their maximum capacity. However, the fact that wind farms operate at less than their maximum capacity is largely immaterial; the critical issue is whether they can supply electricity at a price that is competitive in the electricity market. The fact they do and that financiers continue to invest in wind energy is testament to their efficiency.
There is a considerable amount of variability in the supply of, and demand for, electricity in most electricity systems. The demand for electricity is constantly fluctuating in response to the needs of consumers. Similarly, generators can fail and other unexpected events can occur that cause fluctuations in electricity supply. These fluctuations present a challenge for system operators as supply and demand must be kept in balance in order to ensure the security and reliability of the system. To address this issue, system operators use a number of different measures, including supply forecasting, demand monitoring and what are known as ancillary services.
The current level of wind penetration is too small to cause any significant variability-related problems in the electricity grid. Any variability in the output from wind farms is handled in the same way as other fluctuations in supply and demand. If wind penetration increased substantially, issues could arise. However, research has shown that the electricity grid could readily accept a significant increase in the amount of wind energy if it is not accompanied by a substantial increase in other forms of intermittent generation. Most analysts agree that up to 20 per cent wind capacity penetration is possible without posing any serious technical or practical problems.
For every megawatt hour (MWh) of wind energy, one less MWh of output is needed from another source. As a significant amount of Pakistan’s electricity comes from fossil fuel-based generation, this means that the energy production that is displaced by wind farms is likely to be from coal or gas-fired power stations. By displacing coal and gas-fired generation, wind farms reduce greenhouse emissions. The evidence indicates that a modern 50 megawatt (MW) wind farm operating at 30 per cent capacity will reduce emissions by approximately 120,231 tonnes of CO2-e each year, which is equivalent to the annual emissions from 27,767 cars.
The risk of fire from wind farms is minuscule. In almost 20 years of wind farm operation in other countries, there appears to have been only two fires, neither of which resulted in a wildfire. Provided wind farms are constructed and managed in an appropriate manner, fires caused by wind turbines are likely to be very rare and pose little risk to surrounding property.
The noise pollution from wind turbines is negligible. In fact it is possible to stand underneath a wind turbine and have a normal conversation without raised voices. A modern 10 turbine wind farm would create a sound pressure level of 35 – 45 dBA at 350m, the equivalent of a quiet bedroom or the background noise in a rural area at night.
The available evidence indicates that provided wind farms are located in appropriate areas the risks to biodiversity are likely to be small. Overseas research indicates that the mortality rate for birds and bats from wind turbine collisions is low – typically less than five birds and five bats per turbine per year. If this rate is used as a rough guide, it would suggest that less than 2,550 birds and 2,550 bats currently die each year as a result of collisions with wind turbines. While care should be taken in the site and operation of wind farms, the risks to biodiversity should not be exaggerated and must be weighed against the potential for wind farms to contribute to reducing the severity of the impacts of climate change and energy demands.
When poorly situated, wind farms can have an adverse impact on landscape and heritage values. However, if appropriate planning procedures are followed, the risks to landscape and heritage values should be minimal. Also, any concerns about aesthetics should be considered in the context of climate change and broader community attitudes toward renewable energy.
All electricity systems including the electricity grid have to deal with considerable variability in both the demand for, and supply of, electricity. Each day, demand surges in the early morning as people awake and turn on home appliances and then again in the evening when people return from work. There are also significant day-to-day fluctuations in demand depending on the temperature and business requirements. These short-term variations in demand must be matched by changes in supply in order to keep the electrical system in balance. Unexpected supply-side events can also occur like the loss of generators and interconnectors that put pressure on the system. To ensure reliable access to electricity, the system must be able to respond to these fluctuations.
In conclusion, contrary to what certain anti-wind groups have suggested, the fact that wind is a variable source of energy does not mean that it currently has to be backed up by additional ‘spinning reserves’ from other more reliable sources of electricity to cover periods when there is little or no wind. Wind corridors in Pakistan are good and remain unexplored. The variability associated with wind energy is managed by the measures that are already in place to address fluctuations in the supply of, and demand for, electricity.
Landscape and heritage issues can also be a significant issue for certain wind farms. However, when appropriate planning procedures are followed, the heritage and landscape risks should be minimal. While some people may have a different opinion to wind farms, perhaps on the grounds of aesthetics, but their concerns should be weighed against the need to address the threats posed by climate change and the opinions of the broader community.