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[en] The purpose of this article is to discuss the prospects for a large scale introduction of wind power in the Nordic countries especially with respect to the consequences for small independent power producers of the ongoing and planned deregulation of the electricity sector. The recoverable wind resources are great and integration costs are small due to the good load following capability of the existing Swedish and Norwegian hydroelectric capacity. The structure of the present electricity system and the current principles for electricity trade are reviewed. To what extent wind power will be the technology of choice for capacity replacement and expansion depends on how intermittent power will be valued on the future electricity market. In a deregulated market, wind power may be priced below its value unless appropriate pricing mechanisms are developed. Market reforms should therefore include consideration of the large contribution that wind energy must make in a future electricity system which, in addition to being economically efficient, is compatible with broader societal goals. 47 refs, 2 figs
[en] The investigations took place in a representative area of Karup in the central part of Jutland Denmark. Two wells were augered at localities with different geological and hydrological conditions. The first one Grønhhøj no. 1 is in an unconfined aquifer of the outwashed sand and gravel of the last glaciation, which is the most common geological formation in the area. The land surface slopes slightly 1,2%o to WSW and the depth to the groundwater is about 25 m below land surface. This well is located at the groundwater divide, the depth to water decreases toward a central stream which has a slope of about 1%o The second well is located near Engesvang in the southern part of the representative area, where the geological formations consist of the glacial drift, boulder clay from the Riss-glaciation and layers of meltwater sand. In the clay formation, a perched groundwater aquifer occurs from 5-10 m below land surface. Beneath this aquifer and the boulder clay is a water-table aquifer in the meltwater sand. The groundwater table here is about 25 m below land surface.
[en] The Workshop on Public Benefits and Power Sector Reform was motivated by the need to address broader development goals and advance the provision of public benefits in power sector reforms. The primary objectives were: To provide a forum for a discussion among specialists, of how the provision of public benefits can be expanded as power sectors in developing countries are reformed, and review the experience (Day 1). To identify the needs for training and capacity building and institutional arrangements, as well as make recommendations for their design and implementation, for policy makers, regulators, and other professionals in developing countries (Day 2). Public benefits is a socially constructed concept that includes activities that are not adequately conceived by competitive markets. Public benefit policies and programmes include those that expand electricity access to rural areas and the urban poor, improve security of supply, promote energy efficiency and renewable energy, etc. Reforms have indeed been a threat to public benefits as traditionally delivered through electric utilities. However, in many cases public benefit programmes have also been rescued. In fewer cases, public benefit programmes have been conceived in the reform process. From experience so far it is clear that power sector reforms must be made more compatible with broader sustainable development goals. Recognising the need for broader policy integration and putting public benefits higher on the reform agenda points to the importance of reaching beyond energy ministries and power sector experts at an early stage in the reform process. Other actors, such as NGOs and academia, may also be instrumental in monitoring and assessing the impacts of reform. Public benefits can be an integral part of a reform package, or a complement to reform. It does appear that reform creates space and opportunity to achieve public benefits, but someone has to utilise that opportunity. The need to make trade-offs between potentially conflicting objectives should not be underestimated. However, if reforms are framed around broader development goals priorities will be more explicit, and better informed trade-offs can be made. Perceived conflicts may be removed in the process. Training and capacity building are key approaches to advancing public benefits. Training needs are changing and more specialised training, by topic or country, is needed as reforms evolve. In addition, the target audience should be extended to include a broader range of stakeholders than energy ministries and regulators alone. The international donor community has a specific responsibility to enhance its own capacity in this area as well as to support training and capacity building in order to advance public benefits. Research based analysis and knowledge should be developed and used in training and capacity building, ultimately contributing to shaping policy
[en] In this report the development of Swedish biomass use during recent decades is discussed. The relations between biomass supply, biomass demand and various policy initiatives are explored. The objectives are to discuss the most important factors affecting the biomass development and to establish which factors are specific for Swedish conditions and also to identify general factors that are relevant in assessing the possibility of expanding biomass use in different contexts. The focus is on the use of biomass for heat and electricity production. Biomass contributed 14% to the Swedish energy supply in 1999. The major fraction of Swedish biomass is used within the forest industry (63%) and in district heating systems (23%). The remaining fraction is used in small-scale boilers in one- and two family dwellings. Between 1990 and 1999 Swedish bioenergy use (including waste and peat) increased by 44%. During the same period there has been a fourfold increase in the district heating systems. By-products from forestry and the Swedish forest industry dominate the supply of biomass in Sweden, but the importation of biomass increased significantly during the 1990s. A number of factors of various kinds have interacted to bring about the increased use of biomass in Sweden during the past twenty years. These factors can be divided into three categories: structure, policies and actors. The existence of a major forest industry and well-developed district heating systems has enabled a rapid response to strong and standing policy commitments to biomass. The reformation of the taxation system, with the introduction of a high carbon tax on fossil fuels, has led to significantly improved competitiveness for biomass when used for heating purposes.
[en] Positron emission tomography and the positron camera are described and their applications in medical diagnostics outlined. The incorporation of positron emitting isotopes into other molecules which can participate biochemically in cell metabolisms and accumulate in cells with increased activity, is discussed. (C.F.)
[en] A deep decarbonization of basic materials production fundamentally requires new process technologies. The current climate policy framework tends to preserve industrial structures and reward incremental improvements rather than prepare for a low-carbon transition. G8 countries should develop policies that shift the focus from compensating carbon cost and incremental change to developing technologies and policy strategies for zero carbon emissions by 2050.
[en] The objective of this study was to calculate indicative ranges of production costs and assess the main sources of cost for a number of energy crops, both annual and perennial, on a regional level in Europe. The production costs were calculated in terms of the economic compensation required by the farmer in order to grow the crop, and therefore include not only the cost of cultivation, but also the costs of land and risk, which are often omitted in production cost calculations. The cost of land was calculated as the opportunity cost based on the production of cereals. Thus, higher food prices lead to higher land costs, which in turn lead to higher energy crop production costs. The analysis was performed for three cases with different assumptions concerning yields and production cost reductions resulting from scale (total cultivation area in the region), and learning effects. The calculated energy crop production costs were found to be consistently lowest for short-rotation coppice (SRC) crops and highest for annual straw crops. The production costs of SRC crops were calculated to be about 4-5 EUR GJ-1 under present conditions and 3-4 EUR GJ-1 under improved future conditions. The production costs for perennial grasses were calculated to be about 6-7 EUR GJ-1 and 5-6 EUR GJ-1 under present and improved future conditions, respectively. The production costs for annual straw crops were estimated to be 6-8 EUR GJ-1 under present conditions with small potential for cost reductions in the future. (author)
[en] Artificial neural networks (ANNs) are used to determine the state-of-health (SOH) of the Automated Radioxenon Analyzer/Sampler (ARSA). ARSA is a gas collection and analysis system used for non-proliferation monitoring in detecting radioxenon released during nuclear tests. SOH diagnostics are important for automated, unmanned sensing systems so that remote detection and identification of problems can be made without onsite staff. Both recurrent and feed-forward ANNs are presented. The recurrent ANN is trained to predict sensor values based on current valve states, which control air flow, so that with only valve states the normal SOH sensor values can be predicted. Deviation between modeled value and actual is an indication of a potential problem. The feed-forward ANN acts as a nonlinear version of principal components analysis (PCA) and is trained to replicate the normal SOH sensor values. Because of ARSA's complexity, this nonlinear PCA is better able to capture the relationships among the sensors than standard linear PCA and is applicable to both sensor validation and recognizing off-normal operating conditions. Both models provide valuable information to detect impending malfunctions before they occur to avoid unscheduled shutdown. Finally, the ability of ANN methods to predict the system state is presented
[en] An analysis is presented of the intertemporal choice foundations underlying the conservation or extinction of renewable resources when the resource production function is non-concave and the immediate return function depends on both current consumption and the size of the resource stock. This case may exhibit nonlinear dynamics and extinction is possible from high stocks even if conservation occurs from lower stocks. The paper focusses on the influence of preferences and the production function on the efficiency of: global conservation, the existence of a safe standard of conservation, or extinction. We show that conservation is efficient under weaker conditions than the 'δ-productivity' requirements derived in models where return function is not stock-dependent. The marginal rate of substitution between investment and the stock plays an important role in addition to the discount factor and the marginal productivity of the resource. Extinction need not be optimal even if the intrinsic growth rate of the resource is less than the external rate of return. Our analysis demonstrates the potential role of taxes, subsidies, demand forces, and harvest costs in determining the efficiency of conservation or extinction. 3 figs., 1 appendix, 24 refs