首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 387 毫秒
1.
This study investigates the use of bioenergy for achieving stringent climate stabilization targets and it analyzes the economic drivers behind the choice of bioenergy technologies. We apply the integrated assessment framework REMIND-MAgPIE to show that bioenergy, particularly if combined with carbon capture and storage (CCS) is a crucial mitigation option with high deployment levels and high technology value. If CCS is available, bioenergy is exclusively used with CCS. We find that the ability of bioenergy to provide negative emissions gives rise to a strong nexus between biomass prices and carbon prices. Ambitious climate policy could result in bioenergy prices of 70 $/GJ (or even 430 $/GJ if bioenergy potential is limited to 100 EJ/year), which indicates a strong demand for bioenergy. For low stabilization scenarios with BECCS availability, we find that the carbon value of biomass tends to exceed its pure energy value. Therefore, the driving factor behind investments into bioenergy conversion capacities for electricity and hydrogen production are the revenues generated from negative emissions, rather than from energy production. However, in REMIND modern bioenergy is predominantly used to produce low-carbon fuels, since the transport sector has significantly fewer low-carbon alternatives to biofuels than the power sector. Since negative emissions increase the amount of permissible emissions from fossil fuels, given a climate target, bioenergy acts as a complement to fossils rather than a substitute. This makes the short-term and long-term deployment of fossil fuels dependent on the long-term availability of BECCS.  相似文献   

2.
This study explores the importance of bioenergy to potential future energy transformation and climate change management. Using a large inter-model comparison of 15 models, we comprehensively characterize and analyze future dependence on, and the value of, bioenergy in achieving potential long-run climate objectives. Model scenarios project, by 2050, bioenergy growth of 1 to 10 % per annum reaching 1 to 35 % of global primary energy, and by 2100, bioenergy becoming 10 to 50 % of global primary energy. Non-OECD regions are projected to be the dominant suppliers of biomass, as well as consumers, with up to 35 % of regional electricity from biopower by 2050, and up to 70 % of regional liquid fuels from biofuels by 2050. Bioenergy is found to be valuable to many models with significant implications for mitigation and macroeconomic costs of climate policies. The availability of bioenergy, in particular biomass with carbon dioxide capture and storage (BECCS), notably affects the cost-effective global emissions trajectory for climate management by accommodating prolonged near-term use of fossil fuels, but with potential implications for climate outcomes. Finally, we find that models cost-effectively trade-off land carbon and nitrous oxide emissions for the long-run climate change management benefits of bioenergy. The results suggest opportunities, but also imply challenges. Overall, further evaluation of the viability of large-scale global bioenergy is merited.  相似文献   

3.
The ability to directly remove carbon dioxide from the atmosphere allows the decoupling of emissions and emissions control in space and time. We ask the question whether this unique feature of carbon dioxide removal technologies fundamentally alters the dynamics of climate mitigation pathways. The analysis is performed in the coupled energy-economy-climate model ReMIND using the bioenergy with CCS route as an application of CDR technology. BECCS is arguably the least cost CDR option if biomass availability is not a strongly limiting factor. We compare mitigation pathways with and without BECCS to explore the impact of CDR technologies on the mitigation portfolio. Effects are most pronounced for stringent climate policies where BECCS is a key technology for the effectiveness of carbon pricing policies. The decoupling of emissions and emissions control allows prolonging the use of fossil fuels in sectors that are difficult to decarbonize, particularly in the transport sector. It also balances the distribution of mitigation costs across future generations. CDR is not a silver bullet technology. The largest part of emissions reductions continues to be provided by direct mitigation measures at the emissions source. The value of CDR lies in its flexibility to alleviate the most costly constraints on mitigating emissions.  相似文献   

4.
In this article, we evaluate and compare results from three integrated assessment models (GCAM, IMAGE, and ReMIND/MAgPIE) regarding the drivers and impacts of bioenergy production on the global land system. The considered model frameworks employ linked energy, economy, climate and land use modules. By the help of these linkages the direct competition of bioenergy with other energy technology options for greenhouse gas (GHG) mitigation, based on economic costs and GHG emissions from bioenergy production, has been taken into account. Our results indicate that dedicated bioenergy crops and biomass residues form a potentially important and cost-effective input into the energy system. At the same time, however, the results differ strongly in terms of deployment rates, feedstock composition and land-use and greenhouse gas implications. The current paper adds to earlier work by specific looking into model differences with respect to the land-use component that could contribute to the noted differences in results, including land cover allocation, land use constraints, energy crop yields, and non-bioenergy land mitigation options modeled. In scenarios without climate change mitigation, bioenergy cropland represents 10–18 % of total cropland by 2100 across the different models, and boosts cropland expansion at the expense of carbon richer ecosystems. Therefore, associated emissions from land-use change and agricultural intensification as a result of bio-energy use range from 14 and 113 Gt CO2-eq cumulatively through 2100. Under climate policy, bioenergy cropland increases to 24–36 % of total cropland by 2100.  相似文献   

5.
Combining bioenergy and carbon dioxide (CO2) capture and storage (CCS) technologies (BECCS) has the potential to remove CO2 from the atmosphere while producing useful energy. BECCS has played a central role in scenarios that reduce climate forcing to low levels such as 2.6 Wm?2. In this paper we consider whether BECCS is essential to limiting radiative forcing (RF) to 2.6 Wm?2 by 2100 using the Global Change Assessment Model, a closely coupled model of biogeophysical and human Earth systems. We show that BECCS can potentially reduce the cost of limiting RF to 2.6 Wm?2 by 2100 but that a variety of technology combinations that do not include BECCS can also achieve this goal, under appropriate emissions mitigation policies. We note that with appropriate supporting land-use policies terrestrial sequestration could deliver carbon storage ranging from 200 to 700 PgCO2-equiavalent over the 21st century. We explore substantial delays in participation by some geopolitical regions. We find that the value of BECCS is substantially higher under delay and that delay results in higher transient RF and climate change. However, when major regions postponed mitigation indefinitely, it was impossible to return RF to 2.6 Wm?2 by 2100. Neither finite land resources nor finite potential geologic storage capacity represented a meaningful technical limit on the ability of BECCS to contribute to emissions mitigation in the numerical experiments reported in this paper.  相似文献   

6.
Transportation contributes to a significant and rising share of global energy use and GHG emissions. Therefore modeling future travel demand, its fuel use, and resulting CO2 emission is highly relevant for climate change mitigation. In this study we compare the baseline projections for global service demand (passenger-kilometers, ton-kilometers), fuel use, and CO2 emissions of five different global transport models using harmonized input assumptions on income and population. For four models we also evaluate the impact of a carbon tax. All models project a steep increase in service demand over the century. Technology change is important for limiting energy consumption and CO2 emissions, the study also shows that in order to stabilise or even decrease emissions radical changes would be required. While all models project liquid fossil fuels dominating up to 2050, they differ regarding the use of alternative fuels (natural gas, hydrogen, biofuels, and electricity), because of different fuel price projections. The carbon tax of 200 USD/tCO2 in 2050 stabilizes or reverses global emission growth in all models. Besides common findings many differences in the model assumptions and projections indicate room for further understanding long-term trends and uncertainty in future transport systems.  相似文献   

7.
John M. DeCicco 《Climatic change》2012,111(3-4):627-640
Public policy supports biofuels for their benefits to agricultural economies, energy security and the environment. The environmental rationale is premised on greenhouse gas (GHG, “carbon”) emissions reduction, which is a matter of contention. This issue is challenging to resolve because of critical but difficult-to-verify assumptions in lifecycle analysis (LCA), limits of available data and disputes about system boundaries. Although LCA has been the presumptive basis of climate policy for fuels, careful consideration indicates that it is inappropriate for defining regulations. This paper proposes a method using annual basis carbon (ABC) accounting to track the stocks and flows of carbon and other relevant GHGs throughout fuel supply chains. Such an approach makes fuel and feedstock production facilities the focus of accounting while treating the CO2 emissions from fuel end-use at face value regardless of the origin of the fuel carbon (bio- or fossil). Integrated into cap-and-trade policy and including provisions for mitigating indirect land-use change impacts, also evaluated on an annual basis, an ABC approach would provide a sound carbon management framework for the transportation fuels sector.  相似文献   

8.
This article presents the synthesis of results from the Stanford Energy Modeling Forum Study 27, an inter-comparison of 18 energy-economy and integrated assessment models. The study investigated the importance of individual mitigation options such as energy intensity improvements, carbon capture and storage (CCS), nuclear power, solar and wind power and bioenergy for climate mitigation. Limiting the atmospheric greenhouse gas concentration to 450 or 550 ppm CO2 equivalent by 2100 would require a decarbonization of the global energy system in the 21st century. Robust characteristics of the energy transformation are increased energy intensity improvements and the electrification of energy end use coupled with a fast decarbonization of the electricity sector. Non-electric energy end use is hardest to decarbonize, particularly in the transport sector. Technology is a key element of climate mitigation. Versatile technologies such as CCS and bioenergy are found to be most important, due in part to their combined ability to produce negative emissions. The importance of individual low-carbon electricity technologies is more limited due to the many alternatives in the sector. The scale of the energy transformation is larger for the 450 ppm than for the 550 ppm CO2e target. As a result, the achievability and the costs of the 450 ppm target are more sensitive to variations in technology availability.  相似文献   

9.
1.5℃温升目标下中国碳排放路径研究   总被引:1,自引:0,他引:1  
《巴黎协定》提出1.5℃目标以及中国2060年前达到碳中和的目标背景下,为研究实现1.5℃目标的技术路径,构建了综合性的能源-经济-环境系统模型,研究中国在2℃情景基础上实现1.5℃目标的额外减排要求、部门贡献和关键减排措施.结果显示,1.5℃情景要求到2050年CO2排放量减少到6亿t.一次能源消费总量2045年达峰...  相似文献   

10.
IPCC第六次评估报告第三工作组报告交通运输章评估了该行业温室气体的减缓措施和转型路径。1990年以来,全球交通运输部门温室气体排放量一直增长,2019年已经成为全球第四大排放源,仅次于电力、工业以及农业、林业和其他土地利用(AFOLU)部门,其增长速度超过其他最终用途行业。报告强调了交通减排的重要性,主要的减排措施包括三方面:首先是减少需求,其次是对陆路交通部门进行脱碳,再次是对重型的水运和航空运输等进行脱碳。评估的多种燃料和动力技术处于不同的商业化水平,它们未来应用时间节点和规模各有不同。对于陆路交通来说,需要继续推进电气化;对于水运和航空来说需要进一步应用低碳技术,并优化国际管理机制;从中长期来看,所有部门都需要强调运输服务需求管理和运输效率的提升。情景相关的文献评述分析表明,全球温升目标要求全经济部门采取减排措施,特别是交通电气化的减排潜力在很大程度上取决于电力部门的脱碳。如果不采取减缓措施,交通运输部门排放在2050年可能增长65%(相对2010年);如果成功实施减缓战略,该部门的排放量将减少68%,这也与全球1.5℃温升目标要求相一致。关于这些减缓措施的分析和判断,对我国交通运输部门实现碳中和与碳达峰具有重要的参考意义。  相似文献   

11.
开展交通领域大气污染物与温室气体协同减排研究对于实现能源、环境和气候变化综合管理具有重要意义。文中以我国交通部门污染物与温室气体协同治理为切入点,开展道路、铁路、水运、航空和管道运输等各子部门未来需求预测,并运用长期能源可替代规划系统模型(LEAP),通过构建基准情景、污染减排情景、绿色低碳情景和强化低碳情景,模拟分析我国交通领域能源需求、污染物及碳排放趋势。结果表明,强化低碳情景下,我国交通部门能源消费将在2037年达峰,CO2排放将在2035年达峰;绿色低碳情景下,CO2排放将在2040年达峰;淘汰老旧汽车、“公转铁”“公转水”等政策性措施将有效减少NOx、PM2.5等污染物排放,发展氢燃料、生物航油等技术性措施将进一步减少污染物排放;要实现交通领域绿色低碳发展,需分别对客运、货运交通从节能降碳与协同减排两方面实施相关措施,综合施策是完成能源消费与碳排放达峰目标的重要保证。  相似文献   

12.
Limiting climate change to 2 °C with a high probability requires reducing cumulative emissions to about 1600 GtCO2 over the 2000–2100 period. This requires unprecedented rates of decarbonization even in the short-run. The availability of the option of net negative emissions, such as bio-energy with carbon capture and storage (BECCS) or reforestation/afforestation, allows to delay some of these emission reductions. In the paper, we assess the demand and potential for negative emissions in particular from BECCS. Both stylized calculations and model runs show that without the possibility of negative emissions, pathways meeting the 2 °C target with high probability need almost immediate emission reductions or simply become infeasible. The potential for negative emissions is uncertain. We show that negative emissions from BECCS are probably limited to around 0 to 10 GtCO2/year in 2050 and 0 to 20 GtCO2/year in 2100. Estimates on the potential of afforestation options are in the order of 0–4 GtCO2/year. Given the importance and the uncertainty concerning BECCS, we stress the importance of near-term assessments of its availability as today’s decisions has important consequences for climate change mitigation in the long run.  相似文献   

13.
An improvement of methods for the inventory of greenhouse gas (GHG) emissions is necessary to ensure effective control of commitments to emission reduction. The national inventory reports play an important role, but do not reflect specifics of regional processes of GHG emission and absorption for large-area countries. In this article, a GIS approach for the spatial inventory of GHG emissions in the energy sector, based on IPCC guidelines, official statistics on fuel consumption, and digital maps of the region under investigation, is presented. We include mathematical background for the spatial emission inventory of point, line and area sources, caused by fossil-fuel use for power and heat production, the residential sector, industrial and agricultural sectors, and transport. Methods for the spatial estimation of emissions from stationary and mobile sources, taking into account the specifics of fuel used and technological processes, are described. Using the developed GIS technology, the territorial distribution of GHG emissions, at the level of elementary grid cells 2 km?×?2 km for the territory of Western Ukraine, is obtained. Results of the spatial analysis are presented in the form of a geo-referenced database of emissions, and visualized as layers of digital maps. Uncertainty of inventory results is calculated using the Monte Carlo approach, and the sensitivity analysis results are described. The results achieved demonstrated that the relative uncertainties of emission estimates, for CO2 and for total emissions (in CO2 equivalent), depend largely on uncertainty in the statistical data and on uncertainty in fuels’ calorific values. The uncertainty of total emissions stays almost constant with the change of uncertainty of N2O emission coefficients, and correlates strongly with an improvement in knowledge about CH4 emission processes. The presented approach provides an opportunity to create a spatial cadastre of emissions, and to use this additional knowledge for the analysis and reduction of uncertainty. It enables us to identify territories with the highest emissions, and estimate an influence of uncertainty of the large emission sources on the uncertainty of total emissions. Ascribing emissions to the places where they actually occur helps to improve the inventory process and to reduce the overall uncertainty.  相似文献   

14.
Bioenergy with carbon capture and storage (BECCS) and afforestation are key negative emission technologies suggested in many studies under 2 °C or 1.5 °C scenarios. However, these large-scale land-based approaches have raised concerns about their economic impacts, particularly their impact on food prices, as well as their environmental impacts. Here we focus on quantifying the potential scale of BECCS and its impact on the economy, taking into account technology and economic considerations, but excluding sustainability and political aspects. To do so, we represent all major components of BECCS technology in the MIT Economic Projection and Policy Analysis model. We find that BECCS could make a substantial contribution to emissions reductions in the second half of the century under 1.5 and 2 °C climate stabilization goals, with its deployment driven by revenues from carbon dioxide permits. Results show that global economic costs and the carbon prices needed to hit the stabilization targets are substantially lower with the technology available, and BECCS acts as a true backstop technology at carbon prices around $240 per tonne of carbon dioxide. If driven by economics alone, BECCS deployment increases the use of productive land for bioenergy production, causing substantial land use changes. However, the projected impact on commodity prices is quite limited at the global scale, with global commodity price indices increasing by less than 5% on average. The effect is larger at the regional scale (up to 15% in selected regions), though significantly lower than previous estimates. While BECCS deployment is likely to be constrained for environmental and/or political reasons, this study shows that the large-scale deployment of BECCS is not detrimental to agricultural commodity prices and could reduce the costs of meeting stabilization targets. Still, it is crucial that policies consider carbon dioxide removal as a complement to drastic carbon dioxide emissions reductions, while establishing a credible accounting system and sustainable limits on BECCS.  相似文献   

15.
It is a broadly accepted fact that a clear reduction of global GHG emissions is required to limit the increase of global warming to a tolerable level. A key issue in this context is the optimal breakdown of reduction targets among different world regions or even countries. Using the European Commission-funded PLANETS project, cost-optimal global burden sharing to reach global GHG reduction targets was analysed, and an optimal allocation of GHG reductions was identified, relative to the global target, to the commitments of different world regions and the trade possibilities for emission certificates. Specifically, it is evaluated how Europe can contribute in a cost-optimal way to keeping the global concentration of GHGs in the atmosphere below 530 parts per million equivalent (ppme) or below a stricter global reduction target of 500 ppme. Based on the energy system model TIMES PanEU, the potentials for emissions reduction in the different energy sectors and EU Member States and the role of key technologies are analysed. The most cost-effective potentials for GHG reductions in Europe are in the conversion/production, residential and industrial sectors. Substantial reductions in the transport sector occur only under very stringent reduction targets. Achieving ambitious reduction targets requires considerable contributions from all EU Member States until 2050.  相似文献   

16.
分析、解读了IPCC第五次评估报告对能源供应,工业,交通,建筑,农业、林业和其他土地利用(AFOLU)等部门温室气体和CO2减排途径和措施评估的主要结论。2000年以来,除了AFOLU,其他部门的温室气体排放量一直在增长。在增加的排放量中能源系统、工业、交通运输和建筑部门分别贡献了47%、30%、11%和3%。未来,这些部门仍将是全球温室气体的主要排放源和减排的重点领域。通过推进技术进步,持续提高能源效率,进一步优化能源结构,提高碳排放效率,提高原材料使用效率,强化废物管理,提高产品使用效率,减少对产品及相应服务的需求以及广泛利用碳捕获与封存和CO2去除技术,到2050年与基准情景相比,这些部门的CO2排放量可减少15%~80%。所有这些减排措施对我国主要部门减排CO2均具有借鉴意义。  相似文献   

17.
Studies show that the ‘well below 2°C’ target from the Paris Agreement will be hard to meet without large negative emissions from mid-century onwards, which means removing CO2 from the atmosphere and storing the carbon dioxide in biomass, soil, suitable geological formations, deep ocean sediments, or chemically bound to certain minerals. Biomass energy combined with Carbon Capture and Storage (BECCS) is the negative emission technology (NET) given most attention in a number of integrated assessment model studies and in the latest IPCC reports. However, less attention has been given to governance aspects of NETs. This study aims to identify pragmatic ways forward for BECCS, through synthesizing the literature relevant to accounting and rewarding BECCS, and its relation to the Paris Agreement. BECCS is divided into its two elements: biomass and CCS. Calculating net negative emissions requires accounting for sustainability and resource use related to biomass energy production, processing and use, and interactions with the global carbon cycle. Accounting for the CCS element of BECCS foremost relates to the carbon dioxide capture rate and safe underground storage. Rewarding BECCS as a NET depends on the efficiency of biomass production, transport and processing for energy use, global carbon cycle feedbacks, and safe storage of carbon dioxide, which together determine net carbon dioxide removal from the atmosphere. Sustainable biomass production is essential, especially with regard to trade-offs with competing land use. Negative emissions have an added value compared to avoided emissions, which should be reflected in the price of negative emission ‘credits’, but must be discounted due to global carbon cycle feedbacks. BECCS development will depend on linkages to carbon trading mechanisms and biomass trading.

Key policy insights

  • A standardized framework for sustainable biomass should be adopted.

  • Countries should agree on a standardized framework for accounting and rewarding BECCS and other negative emission technologies.

  • Early government support is indispensable to enable BECCS development, scale-up and business engagement.

  • BECCS projects should be designed to maximize learning across various applications and across other NETs.

  • BECCS development should be aligned with modalities of the Paris Agreement and market mechanisms.

  相似文献   

18.
The energy sector is the main contributor to GHG emissions in Saudi Arabia. The tremendous growth of GHG emissions poses serious challenges for the Kingdom in terms of their reduction targets, and also the mitigation of the associated climate changes. The rising trend of population and urbanization affects the energy demand, which results in a faster rate of increase in GHG emissions. The major energy sector sources that contribute to GHG emissions include the electricity generation, road transport, desalination plants, petroleum refining, petrochemical, cement, iron and steel, and fertilizer industries. In recent years, the energy sector has become the major source, accounting for more than 90% of national CO2 emissions. Although a substantial amount of research has been conducted on renewable energy resources, a sustainable shift from petroleum resources is yet to be achieved. Public awareness, access to energy-efficient technology, and the development and implementation of a legislative framework, energy pricing policies, and renewable and alternative energy policies are not mature enough to ensure a significant reduction in GHG emissions from the energy sector. An innovative and integrated solution that best serves the Kingdom's long-term needs and exploits potential indigenous, renewable, and alternative energy resources while maintaining its sustainable development stride is essential.

Policy relevance

The main contributor to GHG emissions in Saudi Arabia is the energy sector that accounts for more than 90% of the national CO2 emissions. Tremendous growth of GHG emissions poses serious challenges for the Kingdom in their reduction and mitigating the associated climate changes. This study examines the changing patterns of different activities associated with energy sector, the pertinent challenges, and the opportunities that promise reduction of GHG emissions while providing national energy and economic security. The importance of achieving timely, sustained, and increasing reductions in GHG emissions means that a combination of policies may be needed. This study points to the long-term importance of making near- and medium-term policy choices on a well-informed, strategic basis. This analytical paper is expected to provide useful information to the national policy makers and other decision makers. It may also contribute to the GHG emission inventories and the climate change negotiations.  相似文献   

19.
Carbon capture and storage (CCS) is increasingly depicted as an important element of the carbon dioxide mitigation portfolio. However, critics have warned that CCS might lead to “reinforced fossil fuel lock-in”, by perpetuating a fossil fuel based energy provision system. Due to large-scale investments in CCS infrastructure, the fossil fuel based ‘regime’ would be perpetuated to at least the end of this century.In this paper we investigate if and how CCS could help to avoid reinforcing fossil fuel lock-in. First we develop a set of criteria to estimate the degree of technological lock-in. We apply these criteria to assess the lock-in reinforcement effect of adding CCS to the fossil fuel socio-technical regime (FFR).In principle, carbon dioxide could be captured from any carbon dioxide point source. In the practice of present technological innovations, business strategies, and policy developments, CCS is most often coupled to coal power plants. However, there are many point sources of carbon dioxide that are not directly related to coal or even fossil fuels. For instance, many forms of bio-energy or biomass-based processes generate significant streams of carbon dioxide emissions. Capturing this carbon dioxide which was originally sequestered in biomass could lead to negative carbon dioxide emissions.We use the functional approach of technical innovations systems (TIS) to estimate in more detail the strengths of the “niches” CCS and Bio-Energy with CCS (BECCS). We also assess the orientation of the CCS niche towards the FFR and the risk of crowding out BECCS. Next we develop pathways for developing fossil energy carbon capture and storage, BECCS, and combinations of them, using transition pathways concepts. The outcome is that a large-scale BECCS development could be feasible under certain conditions, thus largely avoiding the risk of reinforced fossil fuel lock-in.  相似文献   

20.
The Agriculture, forestry and other land use (AFOLU) sector as a whole accounts for more than 80% of the total greenhouse gas (GHG) emission in Nepal. This study estimates the GHG emissions from the AFOLU sector in the business as usual (BAU) case during 2010–2050 and identifies the economically attractive countermeasures to abate GHG emissions from the sector at different carbon prices. It also estimates the carbon price elasticity of GHG abatement from the sector. The study finds that enteric fermentation processes in the livestock and emissions from agricultural soils are the two major contributors of GHG emission in AFOLU sector. It identifies no-regret abatement options in the AFOLU sector that could mitigate about 41.5% of the total GHG emission during 2016–2050 in the BAU scenario. There would be a net cumulative carbon sequestration of 16 million tonnes of carbon dioxide equivalent (MtCO2e) at $10 per tonne of carbon dioxide equivalent (tCO2e) during the period. Carbon price above $75/tCO2e is not found to be much effective in achieving significant additional reduction in GHG emissions from the AFOLU sector.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号