Thomas Budde Christensen

Linking climate change mitigation and coastal eutrophication management through biogas technology: Evidence from a new Danish bioenergy concept.

The interest in sustainable bioenergy solutions has gained great importance in Europe due to the need to reduce GHG emissions and to meet environmental policy targets, not least for the protection of groundwater and surface water quality. In the Municipality of Solrød in Denmark, a novel bioenergy concept for anaerobic co-digestion of food industry residues, manure and beach-cast seaweed has been developed and tested in order to quantify the potential for synergies between climate change mitigation and coastal eutrophication management in the Køge Bay catchment. The biogas plant, currently under construction, was designed to handle an annual input of up to 200,000 t of biomass based on four main fractions: pectin wastes, carrageenan wastes, manure and beach-cast seaweed. This paper describes how this bioenergy concept can contribute to strengthening the linkages between climate change mitigation strategies and Water Framework Directive (WFD) action planning. Our assessments of the projected biogas plant indicate an annual reduction of GHG emissions of approx. 40,000 t CO2 equivalents, corresponding to approx. 1/3 of current total GHG emissions in the Municipality of Solrød. In addition, nitrogen and phosphorous loads to Køge Bay are estimated to be reduced by approx. 63 t yr.(-1) and 9 tyr.(-1), respectively, contributing to the achievement of more than 70% of the nutrient reduction target set for Køge Bay in the first WFD river basin management plan. This study shows that anaerobic co-digestion of the specific food industry residues, pig manure and beach-cast seaweed is feasible and that there is a very significant, cost-effective GHG and nutrient loading mitigation potential for this bioenergy concept. Our research demonstrates how an integrated planning process where considerations about the total environment are integrated into the design and decision processes can support the development of this kind of holistic bioenergy solutions.

Risk Perception of Plastic Pollution: Importance of Stakeholder Involvement and Citizen Science

Risk perception has a significant impact on how society reacts to a given risk. There have been cases where a mismatch between the actual risk and the perception of it has led to poor decisions on societal initiatives, such as inappropriate regulatory measures. It is therefore important that the perception of risk is based on an informed foundation acknowledging the biases and drivers that inevitably go with risk perception. Plastic pollution differs in regard to other classical risks, such as those posed by chemicals or genetically modified organisms (GMOs), since the pollution is more visible and already has a significant magnitude. At the same time, everyone is familiar with using plastic, and our daily lives are highly dependent on the use of plastic. This offers some potential to strengthen the societal risk perception and subsequently implement effective measures to address the pollution.

Counting carbon: contextualization or harmonization in municipal GHG accounting?

ABSTRACT This article conducts an assessment of what should be considered best practice in municipal GHG accounting, contrasting the call for increased global harmonization with the need for local relevance and applicability. Taking as its point of departure an analysis of GHG accounting methodologies applied by local governments in Denmark, we identify eight Danish methodologies and assess them based on international good practice criteria. We observe a high degree of convergence among the Danish approaches in the application of data sources, quantification approaches, and scope, identifying data availability as the key barrier to improving the specificity and dynamic properties of local GHG accounts. In furthering an international best practice, the Danish approaches indicate that relevance to local planning necessarily involves an adaptation to the context of local systems and data sources, and that best practice guidelines should acknowledge limitations in inventory quality and provide guidelines for weighing trade-offs and exploring synergetic improvements. In Denmark, synergies can be found in improved data quality and regional cooperation on account development, which may improve relevance, quality, and comparability simultaneously, and act as an adaptive approach to methodology harmonization, without thereby reducing inventory relevance.

Designing models and screening biomass residues for facilitating the implementation of local biomass energy technologies

This article emphasises that biomass can be not only used to produce renewable energy, but also to recover and re-use all types of biomass residues from various sources, and to select energy technologies and systems that allow for the most optimal use of these resources. It focuses on the importance of seeking the highest environmental benefits possible from the use of biomass residues. We argue that this can be achieved by applying the principles of Industrial Ecology in the design of models to enable a transformation to the use of biomass for energy production in local communities. This article develops four such energy-and-business models to be adopted by communities, each dependent on the local context and type of biomass available. The article further exemplifies a screening of relevant biomass residues appropriate for energy production, which might be available in a Chinese context, and thus be utilized in one of the four models developed.