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Management strategies for loblolly pine (Pinus taeda) plantations in the Southeastern USA can be adapted to fulfill both the demand for wood products and for bioenergy. This study quantifies the impact of plantation management choices on the cumulative carbon balance and the net present value of loblolly pine plantations at the stand level, as well as the wood supply cost for bioenergy production for these different management strategies. The strategies assessed (conventional, additional thinning and short rotation) are characterised by planting density, thinning age and rotation period, each with and without collection and utilization of slash residues for bioenergy. The total wood supply costs for bioenergy include the cultivation, harvesting and transport costs for small diameter trees and slash. The results show that the carbon balance after 100 years is 205 (247), 214 (268) and 149 (195) Mg ha−1 for the conventional, additional thinning, and short rotation loblolly pine plantation management strategies (within parentheses: same strategies with slash utilization). The conventional strategy has the lowest wood supply costs for bioenergy, 47 (46) $ Mg−1 pulpwood, followed by the additional thinning strategy, 50 (49) $ Mg−1 pulpwood, and 54 (52) $ Mg−1 pulpwood for the short rotation management strategy. In conclusion, switching from the current conventional strategy without the utilization of slash for bioenergy to an additional thinning strategy with the use of slash increases the overall carbon accumulation by about 31%, at marginally higher wood supply cost. Adapting plantation management strategies can have a positive effect on the economic performance and on the carbon balance of loblolly pine plantations. Integration of wood supply for bioenergy and traditional forestry sectors can lead to co-benefits in terms of cost reduction and carbon accumulation.

This paper aims to provide insights in the cost developments of offshore wind energy in Europe. This is done by analysing 46 operational offshore wind farms commissioned after 2000. An increase of the Capital Expenditures (CAPEX) is found that is linked to the distance to shore and depth of more recent wind farms and commodity prices. Analysis results indicate that these two factors are only responsible for about half of the observed CAPEX increase, suggesting other factors such as turbine market with limited competition also led to an increasing CAPEX. Using CAPEX, Annual Energy Production, Financings costs and Operational Expenditures, the development of average Levelized Cost of Electricity (LCoE) is shown to increase from 120 €/MWh in 2000 towards 190 €/MWh in 2014, which is a direct result of the CAPEX increase. The results indicate very different LCoE values among European countries, from currently about 100 Euro/MWh in Denmark and Sweden to 150-220 Euro/MWh in all other countries investigated suggesting an effect of national policy frameworks on the LCoE of offshore wind energy.