18 IEEE power & energy magazine september/october 2010 R on the winds of change impact of renewables on electricity markets Hugh Rudnick and Luiz A. Barroso Digital Object Identifier 10.1109/MPE.2010.937465 RENEWABLE ENERGY TECHNOL- ogies are being welcomed in many countries worldwide because of their minor or nonimpact on the environment, as compared to the adverse impact of traditional fossil fuel generation alter- natives. Although renewable energy in the form of hydroelectricity has been present since the dawn of electricity, the emphasis is presently on noncon- ventional renewables, such as wind and solar technologies. The threat of climate warming, and the emission-reduction commitments that countries have vol- untarily assumed to fight, has been a strong force. Although these technolo- gies are maturing rapidly, they are still not at the technological and economical state to compete with traditional ones such as natural gas, coal thermal genera- tion, or large hydro. Countries have thus acted proactively to help overcome dif- ferent barriers and force renewables by creating direct support mechanisms to help them develop, thus facilitating the emission reduction objective. Europe has been the main driver in these efforts. Its 20-20-20 plan for 2020 was defined in 2007 as an integrated approach to transform Europe into a highly energy- efficient, low-carbon economy. The 2020 objective of reducing greenhouse gas emissions by at least 20% below 1990 levels coupled with 20% of energy consumption from renewable resources plus a 20% reduction in primary energy use by improving energy efficiency. The European Commission recently pro- posed that the European Union should consider unilaterally moving to a 30% reduction in CO 2 by 2020. As the articles in this issue of IEEE Power & Energy Magazine report, re- ducing the emission impact of fossil fuels is being achieved by the incorpora- tion of renewable energy but not neces- sarily without other impacts. In fact, little attention has been placed on the impact renewables have in other market and societal dimensions, such as costs and prices, network infrastructure, system operation, supply adequacy and security of supply, use of land, and other natural resources. The aim of this issue is thus to identify and quantify those impacts, as seen in different regions of the world. Other insti- tutions are conducting a similar analysis: the In- tergovernmental Panel on Climate Change (IPCC) is presently doing a special report, “Energy Sources and Climate Change Miti- gation,” bringing together experts worldwide for this exercise. Renewables have a larger impact on the use of land, landscape, and other physical resourc- es when compared to conventional fossil fuel technologies, although it is very technologically dependent. Solar energy, for example, requires a much larger area than a coal or a gas power plant to pro- duce a given amount of energy. A wind power plant uses more space per energy produced, although that space can still be used for other functions, like farming. In general, bioenergy is the most land-con- suming technology closely followed by large hydro generation. In terms of water use, renewables, in general, compare favorably with fossil fuel generation, re- quiring significantly smaller amounts of water for cooling purposes. Nevertheless, two IPCC experts, Os- waldo Lucon and Jayant Sathaye, who wrote this issue’s “In My View” col- umn, argue that any utilization of en- ergy causes impacts and that there are always by-products, wastes, and effects from the use of natural resources. Further, they indicate that in the case of renewables, most of these effects are less harmful to the environment and mankind, and where they exist, they can be mitigat- ed. They further empha- size that the outstanding advantage of renewables, which largely surpasses their impacts on use of natural resources, is that they have little or no di- rect local and global at- mospheric emissions. Besides their impact on natural resources, we wanted to assess the im- pacts of renewables on technical and economic dimensions in electri- cal markets worldwide. Economically, renewables do not come without additional expenditure; they have an impact on both costs and final prices, as subsidies or quotas necessar- ily impact markets, tariffs, and their im- plementation impact price volatility and sometimes distort economic balances. guest editorial Renewables have a larger impact on the use of land, landscape, and also on other physical resources when compared to conventional fossil fuel technologies.