Spatio-temporal uncertainty in Spatial Decision Support Systems: A case study of changing land availability for bioenergy crops in Mozambique

Spatial Decision Support Systems (SDSSs) often include models that can be used to assess the impact of possible decisions. These models usually simulate complex spatio-temporal phenomena, with input variables and parameters that are often hard to measure. The resulting model uncertainty is, however, rarely communicated to the user, so that current SDSSs yield clear, but therefore sometimes deceptively precise outputs. Inclusion of uncertainty in SDSSs requires modeling methods to calculate uncertainty and tools to visualize indicators of uncertainty that can be understood by its users, having mostly limited knowledge of spatial statistics. This research makes an important step towards a solution of this issue. It illustrates the construction of the PCRaster Land Use Change model (PLUC) that integrates simulation, uncertainty analysis and visualization. It uses the PCRaster Python framework, which comprises both a spatio-temporal modeling framework and a Monte Carlo analysis framework that together produce stochastic maps, which can be visualized with the Aguila software, included in the PCRaster Python distribution package. This is illustrated by a case study for Mozambique in which it is evaluated where bioenergy crops can be cultivated without endangering nature areas and food production now and in the near future, when population and food intake per capita will increase and thus arable land and pasture areas are likely to expand. It is shown how the uncertainty of the input variables and model parameters effects the model outcomes. Evaluation of spatio-temporal uncertainty patterns has provided new insights in the modeled land use system about, e.g., the shape of concentric rings around cities. In addition, the visualization modes give uncertainty information in an comprehensible way for users without specialist knowledge of statistics, for example by means of confidence intervals for potential bioenergy crop yields. The coupling of spatio-temporal uncertainty analysis to the simulation model is considered a major step forward in the exposure of uncertainty in SDSSs.     

Exploration of regional and global cost–supply curves of biomass energy from short-rotation crops at abandoned cropland and rest land under four IPCC SRES land-use scenarios

We explored the production cost of energy crops at abandoned agricultural land and at rest land at a regional and a global level to the year 2050 using four different land-use scenarios. The estimations were based on grid cell data on the productivity of short-rotation crops on the available land over time and assumptions regarding the capital and the labour input required to reach these productivity levels. It was concluded that large amounts of grown biomass at abandoned agricultural land and rest land, 130–270 EJ yr^?1 (about 40–70% of the present energy consumption) may be produced at costs below $2 GJ^?1 by 2050 (present lower limit of cost of coal). Interesting regions because of their low production cost and significant potentials are the Former USSR, Oceania, Eastern and Western Africa and East Asia. Such low costs presume significant land productivity improvements over time and cost reductions due to learning and capital-labour substitution. An assessment of biomass fuel cost, using the primary biomass energy costs, showed that the future costs of biomass liquid fuels may be in the same order of the present diesel production costs, although this may change in the long term. Biomass-derived electricity costs are at present slightly higher than electricity baseload costs and may directly compete with estimated future production costs of fossil fuel electricity with CO₂ sequestration. The present world electricity consumption of around 20 PWh yr^?1 may be generated in 2050 at costs below $45 MWh^?1 in A1 and B1 and below $55 MWh^?1 in A2 and B2. At costs of $60 MWh^?1, about 18 (A2) to 53 (A1) PWh yr^?1 can be produced.     

您的数据中心是否过冷？冷并不总是好事

任何人都知道数据中心需要保持凉爽,IT设备的最佳工作温度是在20℃到25℃之间,相对应的湿度在40％到55％之间。但是数据中心可能会过冷。     

Macroeconomic impacts of bioenergy production on surplus agricultural land—A case study of Argentina

This paper assesses the macroeconomic impacts in terms of GDP, trade balance and employment of large-scale bioenergy production on surplus agricultural land. An input–output model is developed with which the direct, indirect and induced macroeconomic impacts of bioenergy production and agricultural intensification, which is needed to make agricultural land become available for bioenergy production, are assessed following a scenario approach. The methodology is applied to a case study of Argentina. The results of this study reveal that large-scale pellet production in 2015 would directly increase GDP by 4%, imports by 10% and employment by 6% over the reference situation in 2001. When accounting for indirect and induced impacts, GDP increases by 18%, imports by 20% and employment by 26% compared to 2001. Agricultural intensification reduces but does not negate these positive impacts of bioenergy production. Accounting for agricultural intensification, the increase in GDP as a result of bioenergy production on surplus agricultural land would amount to 16%, 20% in imports and 16% in employment compared to 2001.     

The impact of sustainability criteria on the costs and potentials of bioenergy production – Applied for case studies in Brazil and Ukraine

The goal of this paper is to analyse the impact of the implementation of a certification system on the management system (costs) of and the availability of land (quantity) for bioenergy production. Twelve socio-economic areas of concern (food supply, child labour, (minimum) wages, employment, health care and education) and environmental areas of concern (soil erosion, depletion of fresh water resources, nutrient losses and soil nutrient depletion, pollution from chemicals and biodiversity) are included. Since there is no generally accepted definition of sustainability, a loose and strict set of criteria are defined. Short rotation coppice (SRC) production systems in Ukraine and South East Brazil in 2015 are taken as case studies. The results indicate that it seems feasible to produce biomass for energy purposes at reasonable cost levels and meeting strict sustainability criteria at the same time. The loose set of criteria has no impact on the costs of energy crop production, which are calculated to be 1.7 € GJ^?1 in Brazil and 2.1 € GJ^?1 in Ukraine. The strict set of criteria results in an increase of the costs of energy crop production by 42 % in Brazil and 14 % in Ukraine. In general, compliance with strict socio-economic criteria has a limited impact on the costs, because SRC is relatively labour extensive. Strict environmental criteria likely have a larger impact.     

Benchmarking energy use in the paper industry: a benchmarking study on process unit level

There are large differences between paper mills in, e.g. feedstock use and grades produced, but typical processes are similar in all mills. The aim of this study is to benchmark the specific energy consumption (SEC) of similar processes within different paper mills in order to identify energy improvement potentials at process level. We have defined improvement potentials as measures that can be taken at mill/process level under assumed fixed inputs and outputs. We were able to use industrial data on detailed process level, and we conducted energy benchmarking comparisons in 23 Dutch paper mills. We calculated average SECs per process step for different paper grades, and we were able to identify ranges in SECs between mills producing the same grade. We found significant opportunities for energy efficiency improvement in the wire and press section as well as in the drying section. The total energy improvement potential based on identified best practices in these sections was estimated at 5.4 PJ (or 15 % of the total primary energy use in the selected mills). Energy use in the other processes was found to be too dependent on quality and product specifications to be able to quantify improvement potentials. Our results emphasise that even a benchmark on detailed process level does not lead to clear estimations of energy improvement potentials without accounting for structural effects and without having a decent understanding of the process.     

From the global efforts on certification of bioenergy towards an integrated approach based on sustainable land use planning

This paper presents an overview of 67 ongoing certification initiatives to safeguard the sustainability of bioenergy. Most recent initiatives are focused on the sustainability of liquid biofuels. Content-wise, most of these initiatives have mainly included environmental principles. Despite serious concerns in various parts of the world on the socio-economic impacts of bioenergy production, these are generally not included in existing bioenergy initiatives. At the same time, the overview shows a strong proliferation of standards. The overview shows that certification has the potential to influence direct, local impacts related to environmental and social effects of direct bioenergy production. Key recommendations to come to an efficient certification system include the need for further harmonization, availability of reliable data and linking indicators on a micro, meso and macro levels. Considering the multiple spatial scales, certification should be combined with additional measurements and tools on a regional, national and international level. The role of bioenergy production on indirect land use change (ILUC) is still very uncertain and current initiatives have rarely captured impacts from ILUC in their standards. Addressing unwanted LUC requires first of all sustainable land use production and good governance, regardless of the end-use of the product. It is therefore recommended to extend measures to mitigate impacts from LUC to other lands and feedstock.     

Biofuel production potentials in Europe: Sustainable use of cultivated land and pastures,Part II: Land use scenarios

Europe's agricultural land (including Ukraine) comprise of 164 million hectares of cultivated land and 76 million hectares of permanent pasture. A “food first” paradigm was applied in the estimations of land potentially available for the production of biofuel feedstocks, without putting at risk food supply or nature conservation.Three land conversion scenarios were formulated: (i) A base scenario, that reflects developments under current policy settings and respects current trends in nature conservation and organic farming practices, by assuming moderate overall yield increases; (ii) an environment oriented scenario with higher emphasis on sustainable farming practices and maintenance of biodiversity; and (iii) an energy oriented scenario considering more substantial land use conversions including the use of pasture land.By 2030 some 44–53 million hectares of cultivated land could be used for bioenergy feedstock production. The energy oriented scenario includes an extra 19 million hectares pasture land for feedstocks for second-generation biofuel production chains. Available land is foremost to be found in Eastern Europe, where substantial cultivated areas can be freed up through sustainable gains in yield in the food and feed sector.Agricultural residues of food and feed crops may provide an additional source for biofuel production. When assuming that up to 50% of crop residues can be used without risks for agricultural sustainability, we estimate that up to 246 Mt agricultural residues could be available for biofuel production, comparable to feedstock plantations of some 15–20 million hectares.