Long-Term Analysis of the Spanish Environmental Policies using the Life Cycle Assessment Method and Energy Optimisation Modelling
During last decades the environmental protection awareness has been growing considerably in the European Union. Specially, climate change concern has become one of the foremost problems to fight with. In 2003, the European Commission approved Directive 2003/87/EC establishing a scheme for greenhouse gas (GHG) emission allowance trading. The main objective of this Directive was to promote the reduction of GHG emissions in a cost-effective and economically efficient manner to meet the Kyoto Protocol targets. After that, the European Commission approved Directive 2009/29/EC extending the scope of the previous one and establishing a reduction of 20% in the GHG emissions in 2020 respect to the 1990 level. Analogously, Directive 2001/81/EC set national ceilings for acidification, eutrophication and tropospheric ozone gases. Cement production and electricity generation sectors are two of the main sources of pollutants in the European Union. This work has focused on the environmental consequences and the compliance of the emissions-related Directives in these sectors in Spain. The current work applies the Life Cycle Assessment (LCA) method, an environmental management tool that evaluates the potential environmental impacts of a product or process throughout its entire life cycle, to the cement manufacture in Spain. As a result, main hotspots such as the combustion of fossil and alternative fuels at the kiln have been identified and assessed in detail. Moreover, various technology improvements such as Best Available Techniques (BAT), and material and fossil fuels substitution scenarios have been implemented. Results have revealed that changing the fossil fuels by alternative fuels derived from waste entails significant reductions in most of the impact categories except for eutrophication. In the same manner, to reduce the clinker content in cement diminishes most of the impacts. This measure shows more problems than fuel substitution because it requires substituting the clinker by secondary materials such as blast furnace slag, fly ashes and pozzolanas, at the same time that mechanical and chemical properties of the cement must be preserved. Going further, an exploratory analysis has been made including the CO2 capture technology in the Spanish cement-making. Results have shown the effects of the post-combustion CO2 capture. It has been observed that this technology is very expensive and most of the impact categories such as human toxicity, eutrophication, freshwater ecotoxicity, acidification, photochemical ozone formation and land use change grow by several times. The main problem is the extremely high amount of heat required - the energy penalty - so natural gas and biomass cogeneration (CHP) plants have been proposed as alternatives to substitute the coal-fired CHP plant. Consequently, more research is needed to reduce costs and emissions. Along with the environmental assessment of the cement manufacture, a modelling analysis has been carried out in order to assess these Directives. TIMES-Spain energy optimisation model has been used. Previously, several calibrations, technology updates and other policies implementations have been made. In addition, measures analysed in the LCA study have been implemented in TIMES-Spain. Considering several scenarios related to CO2 emissions, cement demands and investment costs, the effect of the Directives has been analysed from 2010 to the end of horizon, 2050. It has been concluded that Directive 2009/29/EC involves great reductions in CO2 emissions respect to a case without Directive, reaching almost 50% in 2050. The application of Directive 2001/81/EC is not significant from the point of view of the cement-making because NOx and SO2 emissions are already low respect to the total amounts. The high share of the cement sector CO2 emissions respect to the total has shown the difficulties of the cement industry respect to other industries in terms of emissions reduction efforts. Also, it has been observed that CO2 capture technology does not appear except when high cement demands and stringent sectorial CO2 limits are imposed. It has been recommended to reduce the CO2 emissions limits to the cement manufacturing sector in Spain assuming that 2013-2020 allowances allocation does not force the cement producers to make new investments since the expected cement demands are too low. Besides, the application of the emissions-related Directives in the electricity production sector has been assessed. Several calibrations and developments have been implemented in TIMES-Spain. Emissions and fossil fuel prices scenarios have been included. Externalities of the electricity production have been internalised as well as taxes on CO2, NOx and SO2 have been evaluated to assess the Directives effects. As a result, a high contribution of natural gas in the electricity mix takes place when Directives are applied. The evolution of the electricity production system is mainly characterized by the coal phase-out in 2015, followed by the growth of natural gas combined cycle plants and the entrance of natural gas cogeneration plants in industry from 2030. Beyond 2030 renewable technologies are significantly implemented, in particular wind and solar. The contribution of solar photovoltaic plants is remarkable in the long-term. In addition, it has been observed the disappearance of the CO2 emissions in 2035. Taxes on CO2 have effect from 30€/t CO2 in 2030 and 50€/t CO2 in 2050. It has also been relevant the taxation on NOx, especially from 2030 with a considerable growth of natural gas cogeneration plants. Finally, it has been recommended to update Directive 2001/81/EC for establishing a new ceiling for Spain. In particular, the SO2 ceiling should be reduced below 450-500 kt SO2 per year. On the other hand, it has been suggested to extend the target imposed by Directive 2009/29/EC, to a 50% reduction (in absolute CO2) in 2050 respect to the 2005 level. Moreover, 80% reduction target by 2050 has been proved to be achievable. In that case, an energy carrier shift takes place from electricity to heat in industry, residential and commercial sectors. The application of the previous methodologies shows the importance of considering integrated approaches which deal with more than one aspect. In the current work, environmental and prospective strategies have been merged. As a result, interesting conclusions and recommendations have been obtained not only relevant for the Spanish policymakers and industries but also for the Spanish society.
Tesis Doctoral leída en la Universidad Rey Juan Carlos en 2014. Directores de la Tesis: Helena Cabal y Antonio Alonso-Ayuso
- C - Tesis Doctorales