EU climate and energy policy beyond 2020: are additional targets and instruments for renewables economically reasonable?

The European Council has proposed to stick to a more ambitious GHG target but to scrap a binding RES target for the post-2020 period. This is in line with many existing assessments which demonstrate that additional RES policies impair the cost-effectiveness of addressing a single CO2 externality, and should therefore be abolished. Our analysis explores to what extent this reasoning holds in a secondbest setting with multiple externalities related to fossil and nuclear power generation and policy constraints. In this context, an additional RES policy may help to address externalities for which firstbest policy responses are not available. We use a fully integrated combination of two separate models the top-down, global macro-economic model E3MG and the bottom-up, global electricity sector model FTT:Power – to test this hypothesis. Our quantitative analysis confirms that pursuing an ambitious RES target may mitigate nuclear risks and at least partly also negative non-carbon externalities associated with the production, import and use of fossil fuels. In addition, we demonstrate that an additional RES target does not necessarily impair GDP and other macro-economic measures if rigid assumptions of purely rational behaviour of market participants and perfect market clearing are relaxed. Overall, our analysis thus demonstrates that RES policies implemented in addition to GHG policies are not per se welfare decreasing. There are plausible settings in which an additional RES policy may outperform a single GHG/ETS strategy. Due to the fact, however, that i) policies may have a multiplicity of impacts, ii) the size of these impacts is subject to uncertainties and iii) their valuation is contingent on individual preferences, an unambiguous, “objective” economic assessment is impossible. Thus, the eventual decision on the optimal choice and design of climate and energy policies can only be taken politically

Stable Carbon and Nitrogen Isotopes in a Peat Profile Are Influenced by Early Stage Diagenesis and Changes in Atmospheric CO2 and N Deposition

In this study, we test whether the δ13C and δ15N in a peat profile are, respectively, linked to the recent dilution of atmospheric δ13CO2 caused by increased fossil fuel combustion and changes in atmospheric δ15N deposition. We analysed bulk peat and Sphagnum fuscum branch C and N concentrations and bulk peat, S. fuscum branch and Andromeda polifolia leaf δ13C and δ15N from a 30-cm hummock-like peat profile from an Aapa mire in northern Finland. Statistically significant correlations were found between the dilution of atmospheric δ13CO2 and bulk peat δ13C, as well as between historically increasing wet N deposition and bulk peat δ15N. However, these correlations may be affected by early stage kinetic fractionation during decomposition and possibly other processes. We conclude that bulk peat stable carbon and nitrogen isotope ratios may reflect the dilution of atmospheric δ13CO2 and the changes in δ15N deposition, but probably also reflect the effects of early stage kinetic fractionation during diagenesis. This needs to be taken into account when interpreting palaeodata. There is a need for further studies of δ15N profiles in sufficiently old dated cores from sites with different rates of decomposition: These would facilitate more reliable separation of depositional δ15N from patterns caused by other processes