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1.
In producing power, humans move the nutrients nitrogen (N) and phosphorus (P) from their long‐term geological and biological stocks and release or emit them in soil, water, and the atmosphere. In Finland, peat combustion is an important driver of N and P fluxes from the environment to human economy. The flows of N and P in the Finnish energy system were quantified with partial substance flow analysis, and the driving forces of emissions of nitrogen oxides (NOx) were analyzed using the ImPACT model. In the year 2000 in Finland, 140,000 tonnes of nitrogen entered the energy system, mainly in peat and hard coal. Combustion released an estimated 66,000 tonnes of N as nitrogen oxides (NOx) and nitrous oxides (N2O) and another 74,000 tonnes as elemental N2. Most of the emissions were borne in traffic. At the same time, 6,000 tonnes of P was estimated to enter the Finnish energy system, mostly in peat and wood. Ash was mainly used in earth construction and disposed in landfills; thus negligible levels of P were recycled back to nature. During the twentieth century, fuel‐borne input of N increased 20‐fold, and of P 8‐fold. In 1900–1950, the increasing use of hard coal slowly boosted N input, whereas wood fuels were the main carrier of P. Since 1970, the fluxes have been on the rise. NOx emissions leveled off in the 1980s, though, and then declined in conjunction with improvements in combustion technologies such as NOx removal (de‐NOx) technologies in energy production and catalytic converters in cars.  相似文献   

2.
The environmental impacts of data centers that provide information and communication technologies (ICTs) services are strongly related to electricity generation. With the increasing use of ICT, many data centers are expected to be built, causing more absolute impacts on the environment. Given that electricity distribution networks are very complex and dynamic systems, an environmental evaluation of future data centers is uncertain. This study proposes a new approach to investigate the consequences of future data center deployment in Canada and optimize this deployment based on the Energy 2020 technoeconomic model in combination with life cycle assessment methodology. The method determines specific electricity sources that will power the future Canadian data centers and computes related environmental impacts based on several indicators. In case‐study scenarios, the largest deployment of data centers leads to the smallest impact per megawatt of data centers for all of the environmental indicators. It is found that an increase in power demand by data centers would lead to a reduction in electricity exports to the United States, driving the United States to generate more electricity to meet its energy demand. Given that electricity generation in the United States is more polluting than in Canada, the deployment of data centers in Canada is indirectly linked to an increase in overall environmental impacts. However, though an optimal solution should be found to mitigate global greenhouse gas emissions, it is not clear whether the environmental burden related to U.S. electricity generation should be attributed to the Canadian data centers.  相似文献   

3.
Business‐to‐business (B2B) electronics account for a significant volume of the electrical and electronic equipment (EEE) put on the market. Very little B2B waste electrical and electronic equipment (WEEE) is reported as collected in the European Union (EU) in compliance with the WEEE Directive, which uses the policy principle of extended producer responsibility (EPR) to ensure that WEEE is managed correctly. This presents a barrier to parties looking for access to the waste. Company practice dictates the channels into which B2B WEEE flows following primary use. This article presents a study that engaged with company actors directly to get a better understanding of business information technology (IT) EEE asset management. Data were collected to determine the barriers current practice could present to the collection of B2B IT EEE at end of life and the implications of these for the development of policies and strategies for EPR. A questionnaire was developed and data were gathered from organizations in three EU countries—the United Kingdom, Germany, and France—stratified by size. Some notable findings were that there are several routes by which end‐of‐life B2B WEEE can flow. The recycling and refurbishment of B2B IT units at end of use was shown to be commonplace, but it is likely that these units enter streams where they are not reported. The actors disposing of their units did not have information on the management or disposition of these streams. It is concluded that to achieve the goals of EPR for B2B IT WEEE, the networks and the operational practices of these streams need to be better understood when developing strategies and policies.  相似文献   

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