• Energy Research

Abstract Making new plants CO 2 capture ready (CCR) would enable them to retrofit to capture CO 2 at a later date at lower cost when the appropriate policy and/or economic drivers are in place. In order to understand the economic value and investment characteristics of making new plants CCR in China, a typical 600 MW pulverised coal-fired ultra-supercritical power plant, locating in Guangdong province, was examined. Combined with an engineering assessment, costs were estimated for different CCR scenarios. To analyze CCR investment opportunities, the paper applies a cash flow model for valuing capture options and CCR investment. Results were obtained by Monte-Carlo simulation, based on engineering surveys and an IEA GHG CCR study, as well as plant performance information and expert projections on carbon prices, coal prices and electricity prices. CCR investments are justified by factors such as higher retrofitting probabilities, lower early closure probabilities and fair economic return. However, the economic case for CCR largely depends on two factors: (a) whether the original plant is retrofittable without CCR; and (b) the type of investments made, for example, investments essential to CCR tend to be more economic than additional non-essential CCR features such as clutched low pressure turbines. The carbon price and discount rate were found to have significant impacts on the economics of CCR. Overall, it appears that the value of the ‘capture options’ that CCR generates for retrofitting CCS is significant, and so could justify a modest CCR investment, even assuming the original plant is retrofittable without CCR. It was also found the value of CCR might be significantly understated if the range of potential retrofitting dates is artificially constrained.

AbstractWe examine the evolution of Chinese stakeholder views on CCS over the past six years. The first major survey conducted in 2006 sought to understand views on deploying CCS technologies in China. In 2009, a second survey had the primary goal of understanding stakeholder perceptions of technology choice and financing issues for the first large-scale CCS demonstration projects in China. The latest consultation in 2012, building on previous surveys, investigates stakeholder perceptions as well as behavioural issues affecting preferences. In total, over 350 stakeholders were consulted from 2006 to 2012. Climate change is found to have risen dramatically as a priority for all stakeholders. The potential of CCS is more widely acknowledged, but more so by industry and less among government officials. Knowledge of CCS has also increased substantially. Post-combustion technologies are increasingly viewed as the preferred capture technology and some form of utilization, increasingly enhanced oil recovery, is preferred for CO2 storage. Aside for concern over CO2 storage risk, which remained high, attention moved from a focus on third party exposure (e.g. health and safety risks) to direct risks (e.g. the cost of CO2 capture). The expectation of international financial support for demonstrating CCS in China had shifted over time and has gradually diminished.

Abstract Most climate change mitigation scenarios restricting global warming to 1.5 °C rely heavily on negative emissions technologies and practices (NETPs). Here we updated previous literature reviews and conducted an analysis to identify the most appealing NETPs. We evaluated 36 NETPs configurations considering their technical maturity, economic feasibility, greenhouse gas removal potential, resource use, and environmental impacts. We found multiple trade-offs among these indicators, which suggests that a regionalised portfolio of NETPs exploiting their complementary strengths is the way forward. Although no single NETP is superior to the others in terms of all the indicators simultaneously, we identified 16 Pareto-efficient NETPs. Among them, six are deemed particularly promising: forestation, soil carbon sequestration (SCS), enhanced weathering with olivine and three modalities of direct air carbon capture and storage (DACCS). While the co-benefits, lower costs and higher maturity levels of forestation and SCS can propel their rapid deployment, these NETPs require continuous monitoring to reduce unintended side-effects—most notably the release of the stored carbon. Enhanced weathering also shows an overall good performance and substantial co-benefits, but its risks—especially those concerning human health—should be further investigated prior to deployment. DACCS presents significantly fewer side-effects, mainly its substantial energy demand; early investments in this NETP could reduce costs and accelerate its scale-up. Our insights can help guide future research and plan for the sustainable scale-up of NETPs, which we must set into motion within this decade.

Abstract In Part 1, we presented the findings of the EU ACCSEPT project (2006–2007) with regards to scientific, technical, legal and economic issues. In Part 2, we present the analysis of social acceptability on the part of both the lay public and stakeholders. We examine the acceptability of CO2 capture and geological storage (CCS) within the Clean Development Mechanism (CDM) of the Kyoto Protocol. The debate over the inclusion of CCS within the CDM is caught-up in a set of complex debates that are partly technical and partly political and, therefore, difficult, and time-consuming, to resolve. We explore concerns that support for CCS will detract from support for other low-carbon energy sources. We can find no evidence that support for CCS is currently detracting from support for renewable energy sources, though it is probably too early to detect such an effect. Efforts at understanding, engaging with, and communicating to, the lay public and wider stakeholder community (not just business) in Europe are currently weak and inadequate, despite well-meaning statements from governments and industry.

Building lifetime and stock turnover are both key determinants in modelling building energy and carbon. However in China, aside from anecdotal claims that urban residential buildings are generally short-lived, there are no recent official statistics, and empirical data are extremely limited. We present a system dynamics model where survival analysis is used to characterise the dynamic interplay between new construction, aging, and demolition of residential buildings in urban China. The uncertainties associated with building lifetime were represented using a Weibull distribution, whose shape and scale parameters were calibrated based on official statistics on floor area up to 2006. The calibrated Weibull lifetime distribution allowed us to estimate the dynamic stock turnover of Chinese urban residential buildings for 2007 to 2017. We find that the average lifetime of urban residential buildings was around 34 years, and the overall residential stock size reached 23.7 billion m2 in 2017. The resultant age-specific sub-stocks provide a baseline for the overall stock, which—along with the calibrated Weibull lifetime distribution—can be used in further modelling and for analysis of policies to reduce the whole-life embodied and operational energy and CO2 emissions in Chinese residential buildings.

No abstract. First para: The European Union (EU) has recently initiated the debate on its 2040 climate targets with the EU Commission’s proposal of a net 90% greenhouse gas emission reduction target relative to 1990 (EC 2024a). The EU Commission’s impact assessment indicates that carbon dioxide removals (CDR) will play an important role in the EU’s climate policy for 2040, on a path to EU’s climate neutrality target in 2050 (EC 2024b). The science behind CDR’s importance is clear: drastic and sustained emission reductions need to be supplemented with carbon dioxide (CO2) removals to meet the Paris Agreement objectives, and to reach the EU’s carbon neutrality target by 2050 (IPCC AR6, ESABCC 2023). The need for CDR in 1.5°C pathways reaching net-zero CO2 by 2050 globally is generally projected to be higher than 10 Gt CO2yr-1 removal in 2050 (Prütz et al. 2023). Despite this, emission reductions need to be prioritized as we cannot guarantee a temperature decline after an overshoot (Schleussner et al. 2023). One way to avoid mitigation deterrence is to create separate targets for emission reductions, permanent CDR, and the land use, land use-change, and forestry (LULUCF) sector for the EU 2040 climate framework (Reiner et al. 2021, NEGEM 2023).