Marine Renewables Respecting the Environment

Worldwide raising energy consumption demand gives a fast development of marine renewable energy (MRE). Here, we give a short overview on the risks and uncertainties that may affect the marine environment by these installations. Knowledge transfer from traditional offshore industries and the gain of new knowledge through environmental monitoring, applying old and new methods and standardised data collection will give further insights to understand changes induced by MRE on marine biodiversity and ecosystem functioning. Forecasting models for array effects will contribute to the indicating of MRE development respecting the environment

Tackling complexity and problem formulation in rural electrification through conceptual modelling in system dynamics

Mini-grids are considered important in order to improve access to electricity in developing countries. Their technical and organizational independence from the large national grids and their interactions with local social, economic, and environmental factors suggests that system dynamics is a useful method of analysis. However, the successful implementation of mini-grids in rural electrification has partly been prevented due to complexity issues, making problem formulation difficult. Most problem-solving methods, such as system dynamics, require well-defined problems. Previous work on the problem formulation process in system dynamics is limited. This work presents a conceptual framework for tackling complexity and uncertainties in rural electrification. The conceptual framework is general and draws on research in conceptual modelling and system dynamics. The focus is on the learning that can be achieved from a system description and how it can be used to tackle complexity by reducing uncertainties and improving knowledge

Normative ethics and methodology for life cycle assessment

Prospective life cycle assessment (LCA) provides information on the environmental consequences of individual actions. Retrospective LCA provides information about the environmental properties of the life cycle investigated and of its subsystems. In this paper we analyse the links between the choice of methodology and different theories of normative moral philosophy. The choice of electricity data in an LCA of a conference site with local hydropower production is discussed as an illustration. The two types of LCA can be related to different theories on the characteristics of a good action. Each type of LCA, as well as each of the moral theories, can be criticised from the alternative point of departure. Decisions based on retrospective LCA can have environmentally undesirable consequences. On the other hand, prospective LCA can appear unfair and result in environmentally sub-optimised systems. Both types of LCA also have methodological limitations. We cannot conclude that one type is superior to the other, but the choice of methodology should be consistent with the information sought in the LCA

Linking household and productive use of electricity with mini-grid dimensioning and operation

Off-grid systems, and mini-grids in particular, are expected to play a significant role in improving electricity access to one billion people until 2040. One of the major challenges for mini-grids is associated with their high costs, low financial viability and local development impact. Productive use of electricity can be an important driver of local development and impacts the total load in a mini-grid. By using a mixture of high-resolution (minutes) measurements and long-term data (years) on electricity expenditures and purchased electricity from a mini-grid in the Tanzanian highlands, we analyse the technical and economic impact from household and productive use of electricity, respectively. The high-resolution data is analysed using performance indicators and the long-term data using regression tools. We find that a mixture of household use and productive use of electricity provides both technical and economic benefits for the operator. In addition, we find that while productive use customers only represent 25% of the customers, they generate 44% of the operator\u27s income. Furthermore, productive use of electricity customers are also likely responsible for the peak demand in the mini-grid, which occurs during day time. Lastly, we find empirical evidence suggesting that expenditures and demand are unit elastic, which has implications on economic policies for supporting rural electrification

Prospective Life Cycle Assessment of Graphene Production by Ultrasonication and Chemical Reduction

One promising future bulk application of graphene is as composite additive. Therefore, we compare two production routes for insolution graphene using a cradle-to-gate lifecycle assessment focusing on potential differences in energy use, blue water footprint, human toxicity, and ecotoxicity. The data used for the assessment is based on information in scientific papers and patents. Considering the prospective nature of this study, environmental impacts from background systems such as energy production were not included. The production routes are either based on ultrasonication or chemical reduction. The results show that the ultrasonication route has lower energy and water use, but higher human and ecotoxicity impacts, compared to the chemical reduction route. However, a sensitivity analysis showed that solvent recovery in the ultrasonication process gives lower impacts for all included impact categories. The sensitivity analysis also showed that solvent recovery is important to lower the blue water footprint of the chemical reduction route as well. The results demonstrate the possibility to conduct a life cycle assessment study based mainly on information from patents and scientific articles, enabling prospective life cycle assessment studies of products at early stages of technological development

Challenges in Exposure Modeling of Nanoparticles in Aquatic Environments

Managing the potential environmental risks of nanoparticles requires methods to link nanoparticle properties with macro-scale risks. This study outlines challenges in exposure modeling of nanoparticles in aquatic environments, such as the role of natural organic matter, natural colloids, fractal dimensions of agglomerates, coatings and doping of particles, and uncertainties regarding nanoparticle emissions to aquatic environments. The pros and cons of the exposure indicators mass concentration, particle number concentration, and surface area are discussed. By applying colloid chemistry kinetic equations describing particle agglomeration and sedimentation for the case of titanium dioxide nanoparticles, a limited exposure assessment including some of the factors mentioned is conducted with particle number concentration as the exposure indicator. The results of the modeling indicate that sedimentation, shear flows, and settling are of less importance with regard to particle number based predicted environmental concentrations. The inflow of nanoparticles to the water compartment had a significant impact in the model, and the collision efficiency (which is affected by natural organic matter) was shown to greatly affect model output. Implications for exposure modeling, regulation and science are discussed. A broad spectrum of scientific disciplines must be engaged in the development of exposure models where nano-level properties are linked to macro-scale risk

How to make policy-relevant life cycle assessments of future products? Lessons learned from nanomaterials

Many new nanomaterials are currently being developed, and there is a great demand from policy-makers such as governments and agencies to understand the future environmental impact of nanomaterials. However, assessing the life cycle environmental impacts, e.g. in terms of emissions and energy use, related to these materials and products that contain them constitutes a great challenge, which makes it difficult to meet such needs from policy-makers. The challenge is much due to the many uncertainties that surround new nanomaterials at an early point of technological development, which makes environmental assessment methods such as life cycle assessment difficult to apply. These uncertainties include the future areas of application of the nanomaterial, future designs of products within those areas, and future production processes. When one or more of these uncertainties are present, we say that the life cycle or product chain is embryonic. This embryonic nature of nanomaterial life cycles differentiates them from the life cycles of more established products, such as cups and cucumbers. Assessing the environmental impacts of embryonic nanomaterial life cycles requires the assessor to understand the future, or rather some aspects of a number of possible futures. Hence, we need to make use of methods belonging to the field of future studies, including monitoring of trends in technology development (e.g. via patent analysis) and application areas as well as predicting and exploring by trend analysis, expert judgement, and sometimes even fantasizing. We illustrate the theoretical concept of embryonic life cycles with a number of examples of embryonic nanomaterial life cycles, including carbon nanotubes in composites, titanium dioxide nanoparticles in self-cleaning cement and graphene in electronic devices and composites. We show that a range of future study approaches may enrich, or even be essential to, policy-relevant life cycle assessments. We also show that environmental assessments such as life cycle assessment can be misused or used in questionable ways when applied to embryonic life cycles with the purpose of obtaining policy-relevant results

Live and Let Die? Life Cycle Human Health Impacts from the Use of Tire Studs

Studded tires are used in a number of countries during winter in order to prevent accidents. The use of tire studs is controversial and debated because of human health impacts from increased road particle emissions. The aims of this study are to assess whether the use of tire studs in a Scandinavian studded passenger car actually avoids or causes health impacts from a broader life cycle perspective, and to assess the distribution of these impacts over the life cycle. Life cycle assessment is applied and the disability-adjusted life years indicator is used to quantify the following five types of health impacts: (1) impacts saved in the use phase, (2) particle emissions in the use phase, (3) production system emissions, (4) occupational accidents in the production system, and (5) conflict casualties from revenues of cobalt mining. The results show that the health benefits in the use phase in general are outweighed by the negative impacts during the life cycle. The largest contribution to these negative human health impacts are from use phase particle emissions (67–77%) and occupational accidents during artisanal cobalt mining (8–18%). About 23–33% of the negative impacts occur outside Scandinavia, where the benefits occur. The results inform the current debate and highlight the need for research on alternatives to tire studs with a positive net health balance