Firm Type,Feed‐in Tariff,and Wind Energy Investment in Germany: An Investigation of Decision Making Factors of Energy Producers Regarding Investing in Wind Energy Capacity

The development of renewable and sustainable energy is advanced by public financial support. This is particularly so in the German Energiewende, which seeks to replace nuclear and fossil electricity generation with wind, sun, and biomass. We study the impact of the (changes in the) feed‐in tariff (FIT) policy on the investment in wind electricity generation capacity in Germany in the period 2000–2014. We estimate a generic investment model that includes this support mechanism, the cost of capital, investment risks such as wind and price volatility, and manufacturing costs. We discuss specific features for different types of wind energy investors, such as the incumbents, small private investors, diversified companies, and independent power producers. We find that a change in the FIT has a negative impact on investment capacity regarding the generation of wind energy: A one monetary unit increase in the variation of the tariff is to be associated with a decrease by 0.17 megawatts of wind capacity installed. We argue that it is policy uncertainty that makes investors shy away from making real investments. We also argue that the drivers for wind energy investment can differ along different types of firms. For the traditional power producers, especially electricity price volatility, construction costs, and carbon prices seem to matter. But for the other investor types, the FIT is crucial indeed.     

Avoiding investment in fossil fuel assets

Reducing greenhouse gas emissions requires a transformation of capital assets in the economy, especially those for energy supply. This paper explores the hypothesis that economically efficient decarbonization occurs when the demand for fossil fuels declines at the same rate as their capital assets depreciate. In theory this means that new investments in fossil fuel assets are avoided, but without incurring stranded assets. We examine the practicality of this hypothesis using a biophysical economic model of the US energy supply system, with an example focused on impacts of electric vehicles on the petroleum supply chain. We specifically address two questions: (1) What rate of market penetration for electric vehicles is necessary to avoid investments in the petroleum-related assets? (2) How do the costs of upstream capital assets change with the transformation to electric vehicles? High annual depreciation rates for oil refineries (δ = 9.47%) and assets for crude oil extraction (δ = 8.23%) have important impacts on results. To avoid new investment in oil refining assets through widespread electrification of light-duty vehicles, the vehicle stock would need to be transformed in just 4 or 5 years. Under most scenarios, some petroleum pipelines will likely become stranded assets due to their low rate of depreciation (δ = 2.48%). In some scenarios, additional investments in wind and solar power generation surpass oil and gas extraction for about 5 years during the transformation to electric vehicles. Once built, however, wind and solar capital assets last longer, as shown by their low rate of depreciation (δ = 3.26%).     

Risk Management Model of a Micro-Grid Wind Farm

Micro-grid operation mode, which is the combination of a power grid and distributed generation, is the main way for saving investment, reducing energy consumption, and improving a power system's reliability and flexibility, but it has many risks in the process of implementation. In this article, the micro-grid generation structure of a wind farm was established, a processing flow chart of an intelligent management system was drawn, and a risk management model of a micro-grid wind farm was built from the angle of cost risk, including construction of cost risk and operation cost risk models. The construction cost risk model, grid-connected operation, and isolate-operation cost risk model of a micro-grid wind farm were set up by using a mathematical model that consisted of an objective function and constraint conditions. The accuracy of the model was verified through empirical analysis. This provides a reference and mirror for solving grid-connected wind energy problems and gives an important basis for wind energy risk policy-making, and for avoiding the risks in the process of planning, design, and operation management of a wind farm.     

Life cycle assessment of wind farms in Ethiopia

Purpose

The overall aim of this study is to contribute to the creation of LCA database on electricity generation systems in Ethiopia. This study specifically estimates the environmental impacts associated with wind power systems supplying high voltage electricity to the national grid. The study has regional significance as the Ethiopian electric system is already supplying electricity to Sudan and Djibouti and envisioned to supply to other countries in the region.

Materials and methods

Three different grid-connected wind power systems consisting of four different models of wind turbines with power rates between 1 and 1.67 MW were analyzed for the situation in Ethiopia. The assessment takes into account all the life cycle stages of the total system, cradle to grave, considering all the processes related to the wind farms: raw material acquisition, manufacturing of main components, transporting to the wind farm, construction, operation and maintenance, and the final dismantling and waste treatment. The study has been developed in line with the main principles of the ISO 14040 and ISO 14044 standard procedures. The analysis is done using SimaPro software 8.0.3.14 multi-user, Ecoinvent database version 3.01, and ReCiPe 2008 impact assessment method. The assumed operational lifetime as a baseline is 20 years.

Results and discussion

The average midpoint environmental impact of Ethiopian wind power system per kWh electricity generated is for climate change: 33.6 g CO₂ eq., fossil depletion: 8 g oil eq., freshwater ecotoxicity: 0.023 g 1,4-DCB eq., freshwater eutrophication: 0.005 g N eq., human toxicity: 9.9 g 1,4-DCB eq., metal depletion: 18.7 g Fe eq., marine ecotoxicity: 0.098 g 1,4-DCB eq., particulate matter formation: 0.097 g PM10 eq., photochemical oxidant formation: 0.144 g NMVOC, and terrestrial acidification: 0.21 g SO₂ eq. The pre-operation phase that includes the upstream life cycle stage is the largest contributor to all the environmental impacts, with shares ranging between 82 and 96%. The values of cumulative energy demand (CED) and energy return on investment (EROI) for the wind power system are 0.393 MJ and 9.2, respectively.

Conclusion

The pre-operation phase is the largest contributor to all the environmental impact categories. The sensitivity and scenario analyses indicate that changes in wind turbine lifespans, capacity factors, exchange rates for parts, transport routes, and treatment activities would result in significant changes in the LCA results.

     

Energy Harvesting from Breeze Wind (0.7–6 m s−1) Using Ultra‐Stretchable Triboelectric Nanogenerator

Wind is one of the most important sources of green energy, but the current technology for harvesting wind energy is only effective when the wind speed is beyond 3.5–4.0 m s^?1. This is mainly due to the limitation that the electromagnetic generator works best at high frequency. This means that light breezes cannot reach the wind velocity threshold of current wind turbines. Here, a high‐performance triboelectric nanogenerator (TENG) for efficiently harvesting energy from an ambient gentle wind, especially for speeds below 3 m s^?1 is reported, by taking advantage of the relative high efficiency of TENGs at low‐frequency. Attributed to the multiplied‐frequency vibration of ultra‐stretchable and perforated electrodes, an average output of 20 mW m^?3 can be achieved with inlet wind speed of 0.7 m s^?1, while an average energy conversion efficiency of 7.8% at wind speed of 2.5 m s^?1 is reached. A self‐charging power package is developed and the applicability of the TENG in various light breezes is demonstrated. This work demonstrates the advantages of TENG technology for breeze energy exploitation and proposes an effective supplementary approach for current employed wind turbines and micro energy structure.     

Usability of national reporting data as a reference for generic unit processes

Background, aim and scope  Renewable energy sources nowadays constitute an increasingly important issue in our society, basically because of the need for alternative sources of energy to fossil fuels that are free of CO₂ emissions and pollution and also because of other problems such as the diminution of the reserves of these fossil fuels, their increasing prices and the economic dependence of non-producers countries on those that produce fossil fuels. One of the renewable energy sources that has experienced a bigger growth over the last years is wind power, with the introduction of new wind farms all over the world and the new advances in wind power technology. Wind power produces electrical energy from the kinetic energy of the wind without producing any pollution or emissions during the conversion process. Although wind power does not produce pollution or emissions during operation, it should be considered that there is an environmental impact due to the manufacturing process of the wind turbine and the disposal process at the end of the wind turbine life cycle, and this environmental impact should be quantified in order to compare the effects of the production of energy and to analyse the possibilities of improvement of the process from that point of view. Thus, the aim of this study is to analyse the environmental impact of wind energy technology, considering the whole life cycle of the wind power system, by means of the application of the ISO 14040 standard [ISO (1998) ISO 14040. Environmental management—life cycle assessment—principles and framework. International Standard Organization, Geneva, Switzerland], which allows quantification of the overall impact of a wind turbine and each of its component parts using a Life Cycle Assessment (LCA) study. Materials and methods  The procedures, details, and results obtained are based on the application of the existing international standards of LCA. In addition, environmental details and indications of materials and energy consumption provided by the various companies related to the production of the component parts are certified by the application of the environmental management system ISO 14001 [ISO (2004) ISO 14001 Environmental management systems—requirements with guidance for use. International Standard Organization, Geneva, Switzerland]. A wind turbine is analysed during all the phases of its life cycle, from cradle to grave, by applying this methodology, taking into account all the processes related to the wind turbine: the production of its main components (through the incorporation of cut-off criteria), the transport to the wind farm, the subsequent installation, the start-up, the maintenance and the final dismantling and stripping down into waste materials and their treatment. The study has been developed in accordance with the ISO 14044 standard [ISO (2006) ISO 14044: Environmental management—life cycle assessment—requirements and guidelines. International Standard Organization, Geneva, Switzerland] currently in force. Results  The application of LCA, according to the corresponding international standards, has made it possible to determine and quantify the environmental impact associated with a wind turbine. On the basis of this data, the final environmental effect of the wind turbine after a lifespan of 20 years and its subsequent decommissioning have been studied. The environmental advantages of the generation of electricity using wind energy, that is, the reduction in emissions and contamination due to the use of a clean energy source, have also been evaluated. Discussion  This study concludes that the environmental pollution resulting from all the phases of the wind turbine (manufacture, start-up, use, and dismantling) during the whole of its lifetime is recovered in less than 1 year. Conclusions  From the developed LCA model, the important levels of contamination of certain materials can be obtained, for instance, the prepreg (a composite made by a mixture of epoxy resin and fibreglass). Furthermore, it has been concluded that it is possible to reduce the environmental effects of manufacturing and recycling processes of wind turbines and their components. Recommendations and perspectives  In order to achieve this goal in a fast and effective way, it is essential to enlist the cooperation of the different manufacturers.     

A Hybridized Power Panel to Simultaneously Generate Electricity from Sunlight,Raindrops, and Wind around the Clock

With the solar panels quickly spreading across the rooftops worldwide, solar power is now very popular. However, the output of the solar cell panels is highly dependent on weather conditions, making it rather unstable. Here, a hybridized power panel that can simultaneously generate power from sunlight, raindrop, and wind is proposed and demonstrated, when any or all of them are available in ambient environment. Without compromising the output performance and conversion efficiency of the solar cell itself, the presented hybrid cell can deliver an average output of 86 mW m^?2 from the water drops at a dripping rate of 13.6 mL s^?1, and an average output of 8 mW m^?2 from wind at a speed of 2.7 m s^?1, which is an innovative energy compensation to the common solar cells, especially in rainy seasons or at night. Given the compelling features, such as cost‐effectiveness and a greatly expanded working time, the reported hybrid cell renders an innovative way to realize multiple kinds of energy harvesting and as an useful compensation to the currently widely used solar cells. The demonstrated concept here will possibly be adopted in a variety of circumstances and change the traditional way of solar energy harvesting.     

Investment in radiotherapy infrastructure positively affected the economic status of an oncology hospital

BackgroundRadiotherapy is among the most efficient treatment methods of cancer. However, a radiotherapy base needs a substantial financial investment, especially before the beginning of its operation, and in some cases, in developing countries such a huge investment may cause some financial disturbances for a hospital concerned.AimTo assess the influence of investments modernizing the radiotherapy base in the period between 2000 and 2007 on the financial condition of the oncology hospital in the region with population of about 3 million.Material and methodsFinancial reports and medical statistics for the period between 2000 and 2007 from the studied oncology hospital and a recognized staffing model, as well as data on epidemiological situation of the region have been used to calculate the economic effects of financial investment in the radiotherapy base.ResultsThe growth of RT therapeutic potential has been driven by two cost-effective investment programmes. The total amount invested in both programmes was PLN 127,191,000.The number of radiotherapy patients treated in the hospital increased from 2301 in 2000 to 4799 in 2007 with a the same number of five therapeutic machines, although all five of them were replaced over that period. Investments modernizing the radiotherapy base lead to a significant increase in depreciation and operating costs, which adversely affects financial results of the hospital.ConclusionLong term trends showed that investments had positive influence on hospital performance shown both in increased income and larger number of patients treated.     

A Comprehensive Energy and Economic Assessment of Biofuels: When “Green” Is Not Enough

Referee: Dr. Charles A. S. Hall, Department of Environmental Studies, State University of New York, College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210 Biofuel production systems are sometimes claimed to be able to fill in for future fossil fuel shortages as well as to decrease carbon dioxide emissions and global warming. As such, they are often promoted as a “green” alternative to fossil fuels. I present a comprehensive, system-based case study of biofuel production from maize or corn (Zea mays L.) and evaluate it critically in this review. The case study is taken as an example of the comprehensive approach that I suggest for any energy crop. I conclude that the biofuel option on a large scale is not a viable alternative based on economic, energy and eMergy (amount of available energy [exergy] of one form [usually solar] that is directly or indirectly required to provide a given flow or storage of exergy or matter) analyses of the case study data and estimated possible improvement of yield and efficiency. This is true for developed countries due to their huge energy demand compared with what biofuel options are able to supply as well as for developing countries due to the low yield of their agriculture and competition for land and water for food production. However, biofuels may contribute to optimizing the energy and resource balance of agricultural, livestock, or industrial production systems at an appropriate scale. I present a proposal to integrate ethanol production with industrial activities within a “zero emission framework” as a suggestion for optimization strategies capable of making the biofuel option more sustainable and profitable in those cases where it is appropriate.     

Hierarchical genetic-based grid scheduling with energy optimization

An optimization of power and energy consumptions is the important concern for a design of modern-day and future computing and communication systems. Various techniques and high performance technologies have been investigated and developed for an efficient management of such systems. All these technologies should be able to provide good performance and to cope under an increased workload demand in the dynamic environments such as Computational Grids (CGs), clusters and clouds. In this paper we approach the independent batch scheduling in CG as a bi-objective minimization problem with makespan and energy consumption as the scheduling criteria. We use the Dynamic Voltage Scaling (DVS) methodology for scaling and possible reduction of cumulative power energy utilized by the system resources. We develop two implementations of Hierarchical Genetic Strategy-based grid scheduler (Green-HGS-Sched) with elitist and struggle replacement mechanisms. The proposed algorithms were empirically evaluated versus single-population Genetic Algorithms (GAs) and Island GA models for four CG size scenarios in static and dynamic modes. The simulation results show that proposed scheduling methodologies fairly reduce the energy usage and can be easily adapted to the dynamically changing grid states and various scheduling scenarios.     

A Comparative Analysis of Accident Risks in Fossil,Hydro, and Nuclear Energy Chains

This study presents a comparative assessment of severe accident risks in the energy sector, based on the historical experience of fossil (coal, oil, natural gas, and LPG [Liquefied Petroleum Gas]) and hydro chains contained in the comprehensive Energy-related Severe Accident Database (ENSAD), as well as Probabilistic Safety Assessment (PSA) for the nuclear chain. Full energy chains were considered because accidents can take place at every stage of the chain. Comparative analyses for the years 1969–2000 included a total of 1870 severe (≥ 5 fatalities) accidents, amounting to 81,258 fatalities. Although 79.1% of all accidents and 88.9% of associated fatalities occurred in less developed, non-OECD countries, industrialized OECD countries dominated insured losses (78.0%), reflecting their substantially higher insurance density and stricter safety regulations. Aggregated indicators and frequency-consequence (F-N) curves showed that energy-related accident risks in non-OECD countries are distinctly higher than in OECD countries. Hydropower in non-OECD countries and upstream stages within fossil energy chains are most accident-prone. Expected fatality rates are lowest for Western hydropower and nuclear power plants; however, the maximum credible consequences can be very large. Total economic damages due to severe accidents are substantial, but small when compared with natural disasters. Similarly, external costs associated with severe accidents are generally much smaller than monetized damages caused by air pollution.     

Forecasting suitable areas for wind turbine occurrence to proactively improve wildlife conservation

The United States is rapidly expanding production of renewable energy to meet increased energy demands and reduce greenhouse gas emissions. Wind energy is at the forefront of this transition. A central challenge is understanding the nexus between wind energy development and its capacity for negative effects on wildlife causing population declines and habitat loss. Collaboration among conservationists and developers, early in the planning process, is crucial for minimizing wind-wildlife conflicts. Such collaborations require data showing where wind and wildlife impacts occur. To meet this challenge and inform decision-making, we provide natural resource agencies and stakeholders information regarding where future wind turbines may occur, and the potential affects on natural resource management, including the conservation of priority species and their habitats. We developed a machine learning model predicting suitability of wind turbine occurrence (hereafter, wind turbine suitability) across an eight-state region in the United States, representing some of the richest areas of wind potential. Our model incorporates predictor variables related to infrastructure, land ownership, meteorology, and topography. We additionally created a constraint layer indicating areas where wind would likely not be developed because of zoning, protected lands, and restricted federal agency proximity guidelines. We demonstrate how the predictive wind turbine suitability model informs conservation planning by incorporating animal movement models, relative abundance models coupled with spatial conservation planning software, and population density models for three exemplar, high priority species often affected by wind energy: whooping cranes (Grus americana), golden eagles (Aquila chrysaetos), and lesser prairie-chickens (Tympanuchus pallidicinctus). By merging the wind turbine and biological models, we identified conservation priority areas (i.e., places sharing high suitability for wind turbines and species use), and places where wind expansion could minimally affect these species. We use our “species-wind turbine occurrence relationships” to demonstrate applications, illustrating how forecasting areas of wind turbine suitability promotes wildlife conservation. These relationships inform wind energy siting to reduce negative ecological impacts while promoting environmental and economic viability.     

Leptin increases maternal investment

The primary goal of virtually all organisms is to produce genetic offspring, thereby passing on their genes to future generations. Offspring production, however, is limited by available resources within an environment. Moreover, distributing sufficient energy among competing physiological systems is challenging and can result in trade-offs between self-maintenance and offspring investment when resources are limited. In the current study, we tested the hypothesis that the adipose hormone leptin is involved in mediating energetic trade-offs between competing physiological systems. Specifically, we tested the effects of elevated maternal leptin on investment into offspring production versus self maintenance (immune function), in the Siberian hamster (Phodopus sungorus). The current study provides the first evidence that leptin serves as a signal to mothers of available energy resulting in epigenetic effects. Therefore, elevated leptin allows females to retain more embryos to parturition, and rear more offspring to weaning via reduced maternal infanticide. Innate immune response was suppressed seemingly as a result of these enlarged litters, suggesting that the observed fitness increase is not without costs to the mother. Collectively, these findings suggest that leptin plays a critical role in allowing mothers to determine how much energy to invest in the production and care of young versus self-maintenance.     

风险矩阵分级模型在哈尔滨市食品安全风险评估中的建立与应用

目的:建立哈尔滨市风险矩阵分级模型,并应用该模型探索食品污染的风险。方法:采用风险矩阵、文献综述及专家判断法对某年食品安全风险监测中位列化学污染物及微生物污染超标率首位的食品-项目组合,即动物肝脏-克伦特罗组合、水产品-副溶血性弧菌组合进行模型评估。结果:参照风险矩阵,动物肝脏-克伦特罗组合的健康风险分值为6,可以判断哈尔滨市人群由于食用动物肝脏而导致克伦特罗膳食暴露的健康风险等级为"中风险",水产品-副溶血性弧菌组合的健康风险分值为2,可以判断哈尔滨市人群每餐由于食用水产品而导致副溶血性弧菌膳食暴露的健康风险等级为"极低风险"。结论:哈尔滨市该年食品安全总体情况较好,风险等级较低,但部分监测项目存在食品安全风险隐患,应予以关注。     

Computer Simulation of Surface Segregation

Abstract

Computer simulation techniques can now reliably model the surface structure and energies of inorganic solids. We present recent work which has been directed at modelling the segregation of impurities. The techniques are based on energy minimisation where the forces between the atoms are described by the Born model of solids. We initially show that magnesium and calcium segregation to the prism surfaces of alumina reproduce the available experimental data within the uncertainties of the experimental technique. However, reliable experimental data is not always available, and hence we show using the examples of calcium segregation to zirconia surfaces can give insights to the surface structure and provide predictions for experiment to test. Secondly, the simulations can be verified by comparison with morphologies. This is illustrated by comparison of the experimentally determined morphology of calcite with magnesium and lithium impurities with those calculated. Next extensions to the energy minimisation methods are described using dynamical techniques based on lattice and molecular dynamics. Finally, we describe the situation where there is phase separation and the structure and stability of the interface is governed by the epitaxial relations between the underlying oxide and the impurity oxide.     

Global change synergies and trade‐offs between renewable energy and biodiversity

Reliance on fossil fuels is causing unprecedented climate change and is accelerating environmental degradation and global biodiversity loss. Together, climate change and biodiversity loss, if not averted urgently, may inflict severe damage on ecosystem processes, functions and services that support the welfare of modern societies. Increasing renewable energy deployment and expanding the current protected area network represent key solutions to these challenges, but conflicts may arise over the use of limited land for energy production as opposed to biodiversity conservation. Here, we compare recently identified core areas for the expansion of the global protected area network with the renewable energy potential available from land‐based solar photovoltaic, wind energy and bioenergy (in the form of Miscanthus × giganteus). We show that these energy sources have very different biodiversity impacts and net energy contributions. The extent of risks and opportunities deriving from renewable energy development is highly dependent on the type of renewable source harvested, the restrictions imposed on energy harvest and the region considered, with Central America appearing at particularly high potential risk from renewable energy expansion. Without restrictions on power generation due to factors such as production and transport costs, we show that bioenergy production is a major potential threat to biodiversity, while the potential impact of wind and solar appears smaller than that of bioenergy. However, these differences become reduced when energy potential is restricted by external factors including local energy demand. Overall, we found that areas of opportunity for developing solar and wind energy with little harm to biodiversity could exist in several regions of the world, with the magnitude of potential impact being particularly dependent on restrictions imposed by local energy demand. The evidence provided here helps guide sustainable development of renewable energy and contributes to the targeting of global efforts in climate mitigation and biodiversity conservation.     

Life cycle assessment of an offshore grid interconnecting wind farms and customers across the North Sea

Purpose

This study aims to contribute to an improved understanding of the environmental implications of offshore power grid and wind power development pathways. To achieve this aim, we present two assessments. First, we investigate the impacts of a North Sea power grid enabling enhanced trade and integration of offshore wind power. Second, we assess the benefit of the North Sea grid and wind power through a comparison of scenarios for power generation in affected countries.

Methods

The grid scenario explored in the first assessment is the most ambitious scenario of the Windspeed project and is the result of cost minimization analysis using a transmission-expansion-planning model. We develop a hybrid life cycle inventory for array cables; high voltage, direct current (HVDC) links; and substations. The functional unit is 1 kWh of electricity transmitted. The second assessment compares two different energy scenarios of Windspeed for the North Sea and surrounding countries. Here, we utilize a life cycle inventory for offshore grid components together with an inventory for a catalog of power generation technologies from Ecoinvent and couple these inventories with grid configurations and electricity mixes determined by the optimization procedure in Windspeed.

Results and discussion

Developing, operating, and dismantling the grid cause emissions of 2.5 g CO₂-Eq per kWh electricity transmission or 36 Mt CO₂-Eq in total. HVDC cables are the major cause of environmental damage, causing, for example, half of total climate change effects. The next most important contributors are substations and array cabling used in offshore wind parks. Toxicity and eutrophication effects stem largely from leakages from disposed copper and iron mine tailings and overburden. Results from the comparison of two scenarios demonstrate a substantial environmental benefit from the North Sea grid extension and the associated wind power development compared with an alternative generation of electricity from fossil fuels. Offshore grid and wind power, however, entail an increased use of metals and, hence, a higher metal depletion indicator.

Conclusions

We present the first life cycle assessment of a large offshore power grid, using the results of an energy planning model as input. HVDC links are the major cause of environmental damage. There are differences across impact categories with respect to which components or types of activities that are responsible for damage. The North Sea grid and wind power are environmentally beneficial by an array of criteria if displacing fossil fuels, but cause substantial metal use.     

Maintenance energy: a general model for energy-limited and energy-sufficient growth

The new model proposed to account for the energy requirement for growth includes both a constant maintenance energy term (m) independent of the specific growth rate and a term (m′) which decreases linearly with increase in specific growth rate and becomes zero at the maximum specific growth rate. The available data for testing the model do not deviate significantly from the relations predicted. Consistent values of the maximum growth yield (Y _G) can be derived, irrespective of whether the cultures are energy limited or energy sufficient. Attention is drawn to the possibility that the constant maintenance energy term may be estimated from the maximum specific growth rate.     

新疆风力发电减碳效益全生命周期评估

风力发电减碳效益评估有助于从减碳角度更好制定能源发展相关政策。以风力资源总体丰富且亟需发展风力发电以实现能源系统脱碳的新疆为研究区,将生命周期方法与风力发电模型结合,在省、市级尺度分别评估了风力发电全生命周期的排放水平及发电效益,核算了风力发电相对于火力发电和光伏发电的减碳效益,有效弥补了传统生命周期评估中空间差异考虑不充分的问题。结果表明,风机全生命周期平均发电量为13.1×10⁷ kWh,风力发电全生命周期共排放3944.24 tCO₂-eq,通过材料处置回收和循环再利用可减少1424.79 tCO₂-eq。新疆发展风力发电具有低排放强度和高减碳效益的特点,与火电相比可减少97.44%排放,减碳效益平均可达906.72 gCO₂-eq/kWh,并且应优先布局在哈密、巴音郭楞蒙古自治州和北屯市;与光伏相比,减碳效益可分别达到43.85 gCO₂-eq/kWh(衰减率DR=1%)和169.84 gCO₂-eq/kWh(DR=3%),此情景下风电应主要部署在克孜勒苏柯尔克孜自治州、喀什和和田。在风电减碳效益较差地区如石河子市、铁门关市和双河市应考虑利用本地充足太阳能资源发展光伏发电。需注意风电的排放强度和减碳效益在局地小尺度评估中存在不确定性,获取更精细的结果仍需进一步评估。未来应大力发展新疆本地的风电产业,打造绿色供应链和加快发展处置回收技术以增加减碳效益。     

Age-specific resource investment strategies: evidence from female Richardson's ground squirrels (Spermophilus richardsonii)

To avoid a possible cost to their future survival and/or reproduction, individuals must balance their somatic and reproductive investments. The van Noordwijk and De Jong model of resource investment predicts that investments into reproduction and soma can vary among individuals of a population based on the variation in the total amount of energy that individuals acquire. With principal components analysis (PCA), we created two axes of life history for female Richardson's ground squirrels Spermophilus richardsonii : an index of total energy investment (PC1) and an index of investment tactic (PC2). Using these indices, we examined patterns of resource allocation to reproductive and somatic investments. Because yearling female Richardson's ground squirrels complete growth to adult size during pregnancy and early lactation, their somatic needs exceed those of older, fully grown females. Therefore, we predicted that yearlings would show more evidence of a tradeoff between reproductive and somatic investments compared with older females. Both yearling and older females invested four to five times more mass into their litters than into their own body mass. With increasing total investment, yearling females increased investment in both reproduction and themselves, whereas older females invested relatively more in reproduction than themselves. Regardless of age, females that emerged heavier from hibernation invested fewer resources into themselves and more into their litters. Variation in total energy investment and investment tactic indices was similar for yearling and older females. Contrary to our prediction, however, yearling females showed positive associations between reproductive and somatic investments, whereas older females exhibited showed no significant association between reproductive and somatic investments.