Representation of variable renewable energy sources in TIMER,an aggregated energy system simulation model

The power system is expected to play an important role in climate change mitigation. Variable renewable energy (VRE) sources, such as wind and solar power, are currently showing rapid growth rates in power systems worldwide, and could also be important in future mitigation strategies. It is therefore important that the electricity sector and the integration of VRE are correctly represented in energy models. This paper presents an improved methodology for representing the electricity sector in the long-term energy simulation model TIMER using a heuristic approach to find cost optimal paths given system requirements and scenario assumptions. Regional residual load duration curves have been included to simulate curtailments, storage use, backup requirements and system load factor decline as the VRE share increases. The results show that for the USA and Western Europe at lower VRE penetration levels, backup costs form the major VRE cost markup. When solar power supplies more than 30% of the electricity demand, the costs of storage and energy curtailments become increasingly important. Storage and curtailments have less influence on wind power cost markups in these regions, as wind power supply is better correlated with electricity demand. Mitigation scenarios show an increasing VRE share in the electricity mix implying also increasing contribution of VRE for peak and mid load capacity. In the current scenarios, this can be achieved by at the same time installing less capital intensive gas fired power plants. Sensitivity analysis showed that greenhouse gas emissions from the electricity sector in the updated model are particularly sensitive to the availability of carbon capture and storage (CCS) and nuclear power and the costs of VRE.     

Electricity consumption and CO2 capture potential in Spain

In this paper, different electricity demand scenarios for Spain are presented. Population, income per capita, energy intensity and the contribution of electricity to the total energy demand have been taken into account in the calculations. Technological role of different generation technologies, i.e. coal, nuclear, renewable, combined cycle (CC), combined heat and power (CHP) and carbon capture and storage (CCS), are examined in the form of scenarios up to 2050. Nine future scenarios corresponding to three electrical demands and three options for new capacity: minimum cost of electricity, minimum CO₂ emissions and a criterion with a compromise between CO₂ and cost (CO₂-cost criterion) have been proposed. Calculations show reduction in CO₂ emissions from 2020 to 2030, reaching a maximum CO₂ emission reduction of 90% in 2050 in an efficiency scenario with CCS and renewables. The contribution of CCS from 2030 is important with percentage values of electricity production around 22–28% in 2050. The cost of electricity (COE) increases up to 25% in 2030, and then this value remains approximately constant or decreases slightly.     

我国清洁能源碳减排效益分析及发展顺序

发展低碳能源是应对全球气候变化、实现电力低碳化发展的有效途径,最终要以发电技术在具体工程项目中应用来实现,衡量各技术的经济可行性、评价可再生能源发电技术CO2的减排效益是关键。分析了当前我国主要5种低碳发电技术置换火电的碳减排成本及产生的碳减排效益,并对2020年低碳能源发电技术的碳减排潜力进行了测算。结果表明,水电发电成本及相应的碳减排成本最低,核电其次,光伏发电最高,应优先发展水电、大力开发核电,同时积极发展风电等其他低碳能源。     

How carbon pricing changes the relative competitiveness of low-carbon baseload generating technologies

There is wide public debate about which electricity generating technologies will best be suited to reduce greenhouse gas emissions (GHG). Sometimes this debate ignores real-world practicalities and leads to over-optimistic conclusions. Here we define and apply a set of fit-for-service criteria to identify technologies capable of supplying baseload electricity and reducing GHGs by amounts and within the timescale set by the Intergovernmental Panel on Climate Change (IPCC). Only five current technologies meet these criteria: coal (both pulverised fuel and integrated gasification combined cycle) with carbon capture and storage (CCS); combined cycle gas turbine with CCS; Generation III nuclear fission; and solar thermal backed by heat storage and gas turbines. To compare costs and performance, we undertook a meta-review of authoritative peer-reviewed studies of levelised cost of electricity (LCOE) and life-cycle GHG emissions for these technologies. Future baseload electricity technology selection will be influenced by the total cost of technology substitution, including carbon pricing, which is synergistically related to both LCOE and emissions. Nuclear energy is the cheapest option and best able to meet the IPCC timetable for GHG abatement. Solar thermal is the most expensive, while CCS will require rapid major advances in technology to meet that timetable.     

Emissions reduction scenarios in the Argentinean Energy Sector

In this paper the LEAP, TIAM-ECN, and GCAM models were applied to evaluate the impact of a variety of climate change control policies (including carbon pricing and emission constraints relative to a base year) on primary energy consumption, final energy consumption, electricity sector development, and CO₂ emission savings of the energy sector in Argentina over the 2010–2050 period. The LEAP model results indicate that if Argentina fully implements the most feasible mitigation measures currently under consideration by official bodies and key academic institutions on energy supply and demand, such as the ProBiomass program, a cumulative incremental economic cost of 22.8 billion US$(2005) to 2050 is expected, resulting in a 16% reduction in GHG emissions compared to a business-as-usual scenario. These measures also bring economic co-benefits, such as a reduction of energy imports improving the balance of trade. A Low CO₂ price scenario in LEAP results in the replacement of coal by nuclear and wind energy in electricity expansion. A High CO₂ price leverages additional investments in hydropower. By way of cross-model comparison with the TIAM-ECN and GCAM global integrated assessment models, significant variation in projected emissions reductions in the carbon price scenarios was observed, which illustrates the inherent uncertainties associated with such long-term projections. These models predict approximately 37% and 94% reductions under the High CO₂ price scenario, respectively. By comparison, the LEAP model, using an approach based on the assessment of a limited set of mitigation options, predicts an 11.3% reduction. The main reasons for this difference include varying assumptions about technology cost and availability, CO₂ storage capacity, and the ability to import bioenergy. An emission cap scenario (2050 emissions 20% lower than 2010 emissions) is feasible by including such measures as CCS and Bio CCS, but at a significant cost. In terms of technology pathways, the models agree that fossil fuels, in particular natural gas, will remain an important part of the electricity mix in the core baseline scenario. According to the models there is agreement that the introduction of a carbon price will lead to a decline in absolute and relative shares of aggregate fossil fuel generation. However, predictions vary as to the extent to which coal, nuclear and renewable energy play a role.     

中国中长期碳减排战略目标初探(Ⅱ)——中国煤炭消费过程的碳排放及减排措施

中国能源领域排放的二氧化碳主要来自煤炭,因此煤炭消费过程中的碳减排措施尤为重要。煤炭的主要用户是发电部门,基于应对气候变化的需要,煤电行业的低碳途径不得不考虑采用CCS技术。不论是新建燃煤电厂,还是今后在传统电厂改建过程中增设CCS设施已是大势所趋,预计多数仍将采用MEA法脱除烟气中二氧化碳这一成熟技术。由于MEA法技术经济指标不够先进,估计10~20年内必将出现更先进的脱二氧化碳工艺技术。传统的燃煤锅炉增加CCS的经济效益已经逊于IGCC-CCS,预计2020年后IGCC电厂将成为新建煤电厂的首选方案。20年后采用临氢气化炉与燃料电池FC发电相结合、把高温的热能和甲烷的化学能直接转化为电力的IGFC高效燃煤电厂或将成功应用,IGFC综合能量转化效率比IGCC相对高出1/2~3/4,发展前景不可低估。钢铁、水泥和化工等高耗煤工业部门可通过节能和采用CCS技术降低碳排放,其余用煤的工业部门和分散用户则应考虑节能或用天然气等低碳燃料替代,间接起到减排效果。预计2050年燃煤发电和高耗煤工业总计将排放二氧化碳4.6Gt,如果二氧化碳捕集量是2.9Gt,则净排放量为1.7Gt。加上其他难以捕集二氧化碳的工业、部门及民用煤排放二氧化碳1.0Gt,合计二氧化碳净排放量为2.7Gt(情景A)。如果采用更先进的技术和严格的节能减排措施,可减少煤炭消耗0.31Gt标煤,减少二氧化碳排放0.5Gt,使煤源二氧化碳净排放量减少到2.2Gt(情景B)。无论哪种情景,实施CCS的任务都十分艰巨。     

Analysis of possible geological storage of CO2 and nuclear waste in Lithuania

Lithuania is currently dealing with two major problems in energy sector: final closure of Ignalina Nuclear Power plant (Ignalina NPP) in the end of 2009 and nuclear waste disposal and climate change mitigation issues having in mind replacement of nuclear capacities with fossil one and anticipated increase in GHG emissions. Lithuania has two options: to construct new nuclear power plant also taking into account nuclear waste disposal issue or to burn fossil fuel and to apply carbon capture and storage (CCS) for GHG emission reduction. These two options need to be investigated in Lithuania based on various studies conducted in Lithuania and abroad dealing with geological carbon storage and nuclear waste disposal potentials. There are no long-lived nuclear waste geological storage capacities in Lithuania and there is no pilot project on CCS developed in Lithuania. The aim of the article is to analyse and compare geological carbon and nuclear waste storage opportunities in Lithuania and to assess nuclear and carbon capture and storage technologies in terms of costs.     

The energy and environmental implications of UK more electric transition pathways: A whole systems perspective

Electricity generation contributes a large proportion of the total greenhouse gas emissions in the United Kingdom (UK), due to the predominant use of fossil fuel (coal and natural gas) inputs. Indeed, the various power sector technologies [fossil fuel plants with and without carbon capture and storage (CCS), nuclear power stations, and renewable energy technologies (available on a large and small {or domestic} scale)] all involve differing environmental impacts and other risks. Three transition pathways for a more electric future out to 2050 have therefore been evaluated in terms of their life-cycle energy and environmental performance within a broader sustainability framework. An integrated approach is used here to assess the impact of such pathways, employing both energy analysis and environmental life-cycle assessment (LCA), applied on a ‘whole systems’ basis: from ‘cradle-to-gate’. The present study highlights the significance of ‘upstream emissions’, in contrast to power plant operational or ‘stack’ emissions, and their (technological and policy) implications. Upstream environmental burdens arise from the need to expend energy resources in order to deliver, for example, fuel to a power station. They include the energy requirements for extraction, processing/refining, transport, and fabrication, as well as methane leakage that occurs in coal mining activities – a major cotribution – and from natural gas pipelines. The impact of upstream emissions on the carbon performance of various low carbon electricity generators [such as large-scale combined heat and power (CHP) plant and CCS] and the pathways distinguish the present findings from those of other UK analysts. It suggests that CCS is likely to deliver only a 70% reduction in carbon emissions on a whole system basis, in contrast to the normal presumption of a 90% reduction. Similar results applied to other power generators.     

Innovative energy technologies and climate policy in Germany

Due to the size and structure of its economy, Germany is one of the largest carbon emitters in the European Union. However, Germany is facing a major renewal and restructuring process in electricity generation. Within the next two decades, up to 50% of current electricity generation capacity may retire because of end-of-plant lifetime and the nuclear phase-out pact of 1998. Substantial opportunities, therefore, exist for deployment of advanced electricity generating technologies in both a projected baseline and in alternative carbon policy scenarios. We simulate the potential role of coal integrated gasification combined cycle (IGCC), natural gas combined cycle (NGCC), carbon dioxide capture and storage (CCS), and wind power within a computable general equilibrium model of Germany from the present through 2050. These advanced technologies and their role within a future German electricity system are the focus of this paper. We model the response of greenhouse gas emissions in Germany to various technology and carbon policy assumptions over the next few decades. In our baseline scenario, all of the advanced technologies except CCS provide substantial contributions to electricity generation. We also calculate the carbon price where each fossil technology, combined with CCS, becomes competitive. Constant carbon price experiments are used to characterize the model response to a carbon policy. This provides an estimate of the cost of meeting an emissions target, and the share of emissions reductions available from the electricity generation sector.     

Life-cycle energy consumption and greenhouse gas emissions for electricity generation and supply in China

The Well-to-Meter (WTM) analysis module in the Tsinghua-CA3EM model has been used to examine the primary fossil energy consumption (PFEC) and greenhouse gas (GHG) emissions for electricity generation and supply in China. The results show that (1) the WTM PFEC and GHG emission intensities for the 2007 Chinese electricity mix are 3.247 MJ/MJ and 297.688 g carbon dioxide of equivalent (gCO_2,e)/MJ, respectively; (2) power generation is the main contributing sub-stage; (3) the coal-power pathway is the only major contributor of PFEC (96.23%) and GHG emissions (97.08%) in the 2007 mix; and (4) GHG emissions intensity in 2020 will be reduced to 220.470 gCO_2,e/MJ with the development of nuclear and renewable energy and to 169.014 gCO_2,e/MJ if carbon dioxide capture and storage (CCS) technology is employed. It is concluded that (1) the current high levels of PFEC and GHG emission for electricity in China are largely due to the dominant role of coal in the power-generation sector and the relatively low efficiencies during all the sub-stages from resource extraction to final energy consumption and (2) the development of nuclear and renewable energy as well as low carbon technologies such as CCS can significantly reduce GHG emissions from electricity.     

Nuclear power in open energy markets: A case study of Turkey

For many decades, like many developed countries, Turkey has controlled her electricity sector as a state-owned monopoly. However, faced with rapid electricity demand growth, Turkey started to consider nuclear option. The present paper aims at evaluating both the present status of nuclear power in general and its implications for Turkish energy market in particular. After examining existing nuclear power technology and providing a brief overview of nuclear power economics; it focuses on the repercussions of nuclear power for Turkish energy market. The paper concludes that, in the short run, it may be considered to keep nuclear power within Turkish energy mix because it is an important carbon-free source of power that can potentially make a significant contribution to both Turkey's future electricity supply and efforts to strengthen Turkey's security of supply. However, in the long term, nuclear power should be retained in Turkey only if it has a lower cost than competing technologies.     

Carbon capture and storage potential in coal-fired plant in Malaysia—A review

Secure, reliable and affordable energy supplies are necessary for sustainable economic growth, but increases in associated carbon dioxide (CO₂) emissions, and the associated risk of climate change are a cause of major concern. Experts have projected that the CO₂ emissions related to the energy sector will increase 130% by 2050 in the absence of new policies or supply constraints as a result of increased fossil fuel usage. To address this issue will require an energy technology revolution involving greater energy efficiency, increased renewable energies and nuclear power, and the near-decarbonisation of fossil fuel-based power generation. Nonetheless, fossil fuel usage is expected to continue to dominate global energy supply. The only technology available to mitigate greenhouse gas (GHG) emissions from large-scale fossil fuel usage is carbon capture and storage (CCS), an essential part of the portfolio of technologies that is needed to achieve deep global emission reductions. However, CCS technology faces numerous issues and challenges before it can be successfully deployed. With Malaysia has recently pledged a 40% carbon reduction by 2020 in the Copenhagen 2009 Climate Summit, CCS technology is seen as a viable option in order to achieve its target. Thus, this paper studies the potential and feasibility of coal-fired power plant with CCS technology in Malaysia which includes the choices of coal plants and types of capture technologies possible for implementation.     

An integrated scenario analysis for future zero‐carbon energy system

An integrated scenario analysis methodology has been proposed for zero‐carbon energy system in perspectives of social‐economy, environment and technology. By using the methodology, service demands in all sectors were estimated based on social‐economic data, and then the best technology and energy mixes were obtained to meet the service demands. The methodology was applied to Japan toward zero‐carbon energy system out to the year of 2100, and three different scenarios of nuclear power development are considered in light of the Fukushima accident: (i) no further introduction of nuclear, (ii) fixed portion and (iii) no limit of nuclear. The results show that, zero‐carbon energy scenario can be attained in the year 2100 when electricity will supply 75% of total energy consumption, and three power generation scenarios were proposed, 30% renewable and 70% gas‐carbon capture and storage (CCS) in Scenario 1, respective one‐third nuclear, renewable and gas‐CCS in Scenario 2, and 60% nuclear power, 20% renewable and 10% gas‐CCS in Scenario 3. Finally, Scenario 2 is rated as the most balanced scenario by putting emphasis on the availability of diversified power source, considering the inter‐comparison of the three scenarios from the four aspects of cost, CO₂ emission, risk and diversity. Copyright © 2015 John Wiley & Sons, Ltd.     

Development of an Energy‐Economic Model with Endogenous Technological Progress and Feasibility Study of CCS Systems

The main objective of this research is to develop a bottom‐up energy‐economic model considering endogenous technological development. The designed model analyzes the feasibility of CCS technologies in the Japanese electricity market to derive an optimum carbon reduction scenario. Two factors, a learning curve based on learning‐by‐doing and public R&D investment, precede technological progress. The analysis is calculated with a set of scenarios, which is based on alternative assumptions for technological characteristics: chemical and physical carbon absorptive technology. From modeling estimation, we conclude that technological progress reduces the generation costs of conversion technologies with CCS, as a CCS system acquires an additional unit of installation. Generation cost with chemical absorption remarkably reduces its marginal unit cost through a learning mechanism. The supply fraction from a gas‐fired power plant increases over the analytical time period. The introduction of CCS reduces carbon emission level 17% compared to the baseline scenario in 2050. Technological progress has little impact on the total system costs; however, learning‐by‐doing pushes the introduction of CCS into the market rather than into a R&D activity. Research and development efforts in the private sector or knowledge spillover are not modeled in the study; however, they have the potential to contribute to the mitigation of carbon emission as well. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 43(4): 332–351, 2014; Published online 3 October 2013 in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21078     

Boosting new renewable technologies towards grid parity – Economic and policy aspects

The intensity of market penetration and hence the relevance of clean energy technologies in mitigating climate change will greatly depend on their cost-effectiveness. This paper discusses the economic and policy aspects of speeding up the market of these technologies to reach cost parity. A combination of historical energy market dynamics, technology diffusion and endogenous learning models were employed in the analyses. Starting from giving a preferential position to emerging renewable energy technologies in the energy and climate policy, which also means securing adequate financial resources for their deployment, could lead in the base scenario to a full-cost breakthrough of wind power around 2027 and of photovoltaics in 2032. The combined global market share of renewable electricity in 2050 could reach 62% of all electricity (now 19%) of which wind and solar power alone could account for almost two-thirds corresponding to a carbon saving in the range of 8–16 GtCO₂. However, if the new technologies were downgraded in the energy and climate policy context, the combined impact of solar and wind could remain at no less than 11% which would marginalize these technologies in the fight against climate change. The estimates for financial support to achieve cost parity were very sensitive to the assumptions of the input parameters: in the base case the extra costs or learning investments for solar power were €1432 billion and for wind power €327 billion, but with more conservative input data these values could grow manifold. On the other hand, considering the potentially cheaper electricity from new technologies above the cost parity point and putting a price on carbon could result in a positive yield from public support instead of it being regarded merely as unnecessary spending. The findings stress the necessity of long-term policies and strong commercialization strategies to bring the new energy technologies to breakeven point, but also highlight the complexity of assessing the true costs of making new energy technologies fully competitive.     

Oil and natural gas prices and greenhouse gas emission mitigation

The hikes in hydrocarbon prices during the last years have lead to concern about investment choices in the energy system and uncertainty about the costs for mitigation of greenhouse gas emissions. On the one hand, high prices of oil and natural gas increase the use of coal; on the other hand, the cost difference between fossil-based energy and non-carbon energy options decreases. We use the global energy model TIMER to explore the energy system impacts of exogenously forced low, medium and high hydrocarbon price scenarios, with and without climate policy. We find that without climate policy high hydrocarbon prices drive electricity production from natural gas to coal. In the transport sector, high hydrocarbon prices lead to the introduction of alternative fuels, especially biofuels and coal-based hydrogen. This leads to increased emissions of CO₂. With climate policy, high hydrocarbon prices cause a shift in electricity production from a dominant position of natural gas with carbon capture and sequestration (CCS) to coal-with-CCS, nuclear and wind. In the transport sector, the introduction of hydrogen opens up the possibility of CCS, leading to a higher mitigation potential at the same costs. In a more dynamic simulation of carbon price and oil price interaction the effects might be dampened somewhat.     

Joint electricity and carbon market for Northeast Asia energy interconnection

Decarbonization of the electricity sector is crucial to mitigate the impacts of climate change and global warming over the coming decades. The key challenges for achieving this goal are carbon emission trading and electricity sector regulation, which are also the major components of the carbon and electricity markets, respectively. In this paper, a joint electricity and carbon market model is proposed to investigate the relationships between electricity price, carbon price, and electricity generation capacity, thereby identifying pathways toward a renewable energy transition under the transactional energy interconnection framework. The proposed model is a dynamically iterative optimization model consisting of upper- level and lower-level models. The upper-level model optimizes power generation and obtains the electricity price, which drives the lower-level model to update the carbon price and electricity generation capacity. The proposed model is verified using the Northeast Asia power grid. The results show that increasing carbon price will result in increased electricity price, along with further increases in renewable energy generation capacity in the following period. This increase in renewable energy generation will reduce reliance on carbon-emitting energy sources, and hence the carbon price will decline. Moreover, the interconnection among zones in the Northeast Asia power grid will enable reasonable allocation of zonal power generation. Carbon capture and storage (CCS) will be an effective technology to reduce the carbon emissions and further realize the emission reduction targets in 2030-2050. It eases the stress of realizing the energy transition because of the less urgency to install additional renewable energy capacity.     

Impacts of China's emissions trading schemes on deployment of power generation with carbon capture and storage

The establishment of an emissions trading scheme (ETS) in China creates the potential for a “least cost” solution for achieving the greenhouse gas (GHG) emissions reductions required for China to meet its Paris Agreement pledges. China has pledged to reduce CO₂ intensity by 60–65% in 2030 relative to 2005 and to stop the increase in absolute CO₂ emissions around 2030. In this series of studies, we enhance the MIT Economic Projection and Policy Analysis (EPPA) model to include the latest assessments of the costs of power generation technologies in China to evaluate the impacts of different potential ETS pathways on deployment of carbon capture and storage (CCS) technology. This paper reports the results from baseline scenarios where power generation prices are assumed to be homogeneous across the country for a given mode of generation. We find that there are different pathways where CCS might play an important role in reducing the emission intensity in China's electricity sector, especially for low carbon intensity targets consistent with the ultimate goals of the Paris Agreement. Uncertainty about the exact technology mix suggests that decision makers should be wary of picking winning technologies, and should instead seek to provide incentives for emission reductions. While it will be challenging to meet the CO₂ intensity target of 550 g/kWh for the electric power sector by 2020, multiple pathways exist for achieving lower targets over a longer timeframe. Our initial analysis shows that carbon prices of 35–40$/tCO₂ make CCS technologies on coal-based generation cost-competitive against other modes of generation and that carbon prices higher than 100$/tCO₂ favor a major expansion of CCS. The next step is to confirm these initial results with more detailed modeling that takes into account granularity across China's energy sector at the provincial level.