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[en] Highlights: • This work defines the minimum work of separation (MWS) for a capture process. • Findings of the analysis indicated a MWS of 0.158 GJ/t for post-combustion. • A review of commercially available processes based on chemical absorption was made. • A review of learning models was conducted, with the addition on a novel model. • A learning curve for post-combustion carbon capture was successfully designed. - Abstract: Carbon capture is one of the most important alternatives for mitigating greenhouse gas emissions in energy facilities. The post-combustion route based on chemical absorption with amine solvents is the most feasible alternative for the short term. However, this route implies in huge energy penalties, mainly related to the solvent regeneration. By defining the minimum work of separation (MWS), this study estimated the minimum energy required to capture the CO2 emitted by coal-fired thermal power plants. Then, by evaluating solvents and processes and comparing it to the MWS, it proposes the learning model with the best fit for the post-combustion chemical absorption of CO2. Learning models are based on earnings from experience, which can include the intensity of research and development. In this study, three models are tested: Wright, DeJong and D and L. Findings of the thermochemical analysis indicated a MWS of 0.158 GJ/t for post-combustion. Conventional solvents currently present an energy penalty eight times the MWS. By using the MWS as a constraint, this study found that the D and L provided the best fit to the available data of chemical solvents and absorption plants. The learning rate determined through this model is very similar to the ones found in the literature
[en] This article first reviews energy trends and energy policy objectives in Brazil. It then proposes and analyzes 12 policy options for advancing energy efficiency and renewable energy use. The policies are analyzed as a group with respect to their impacts on total energy supply and demand as well as CO2 emissions. It is determined that the policies would provide a broad range of benefits for Brazil including reducing investment requirements in the energy sector, cutting energy imports, lowering CO2 emissions, and providing social benefits
[en] Highlights: • Brazil holds reserves of high ash coal that can only be used in mine-mouth plants. • Water scarcity requires the use of wet or dry cooling systems in several regions. • The co-firing of 30 wt% eucalyptus is possible regarding the biomass availability. • Biomass cultivation would aggravate the water scarcity in several regions. - Abstract: Brazil has favorable edaphoclimatic conditions for the cultivation of biomass for energy. On the other hand, the country plans to expand its thermal power park using fossil fuels, including Brazil’s high ash coal. This study estimates the potential of co-firing biomass from energy forests in power plants fired with Brazilian coal in the state of Rio Grande do Sul, Brazil, focusing on the limits given by biomass and water availability. Results show that the state holds coal reserves that could support a potential of approximately 8 GW. Referring to limits due to water availability, different outcomes were found for the various coal fields in Rio Grande do Sul. The Candiota coal field, which represents the most important coal field, holding a capacity of 4 GW, shows severe restrictions for water availability that would be aggravated by intense eucalyptus cultivation
[en] The production of electricity using concentrated solar power (CSP) technology is not yet possible in Brazil due to the technology’s high capital costs and the lack of a local industry. However, this study introduces a low-cost approach to CSP in Brazil by describing and simulating the operation of hybrid CSP plants that use sustainably managed biomass in Brazil’s semiarid northeast. Biomass hybridisation of a CSP plant with a solar multiple (SM) of 1.2 and a biomass fill fraction (BFF) of 30% can generate electricity at 110 USD/MWh. The high direct normal irradiation (DNI) and the availability of local low-cost biomass in Brazil’s semiarid northeast suggest the possibility of developing a CSP industry capable of supplying low-cost components under a national program framework, with the co-benefits of local job and income generation. For example, the deployment of 10 CSP plants of 30 MWe each would generate 760 direct and indirect jobs during the 24 months of plant construction and approximately 2100 annual jobs associated with the operation and maintenance (O&M) of the generating units. These 10 new units would generate additional local income on the order of USD 57 million. - Highlights: • CSP plant with supplementary biomass hybridisation is a strategic option for Brazil. • DNI and biomass availability in Brazil's semiarid can foster local CSP industry. • LCOE of CSP would cost 11 cent USD/kWh becoming competitive at solar auctions. • Co-benefits of local job and income generation due to CSP in Brazil are high.
[en] Unconventional oil resources are needed to complement petroleum supply in the next decades. However, given the restrictions that pertain to the production of these resources, this article evaluates the availability of Venezuelan unconventional oil for helping meet the future worldwide petroleum demand. Venezuela has the world's second-largest oil reserves, but the majority of it is unconventional extra-heavy oil from the Orinoco Oil Belt. The perspective of Venezuelan production, the ways in which PDVSA, the state oil company, will raise funds for planned investments and the future oil price predictions are used to assess Venezuela's ability to serve as a source of unconventional oil in the coming years. Findings indicate that Venezuelan crude oil will be increasingly able to provide part of the marginal petroleum supply at a level predicted in global scenarios but short of that predicted by the country's government. Operational difficulties and the effort to raise financial resources for the oil production in the Belt require urgency in overcoming difficulties. As conventional production in Venezuela will stabilise in the coming years and the country is dependent on oil production, Venezuela will rely on extra-heavy oil extraction to ensure increased oil production and the stabilisation of internal accounts. - Highlights: • We analyse the future unconventional oil production capacity of Venezuela. • The study is based on operational capacity, investments capacity and future prices. • The study indicates a production shorter than that predicted by the Venezuelan government. • Venezuela can provide part of the marginal petroleum supply in the coming years
[en] Electricity demands in hospitals are characterized by their need for high quality, guaranteed supplies. The existence of captive electricity uses and the size and regularity of the electrical and heat loads required by hospitals are aspects that could well buttress the possibility of installing cogeneration plants fired by natural gas (CHP). The purpose of this paper is to estimate the CHP technical potential in Brazilian hospitals. Based on a classification of Brazilian hospitals by specific energy consumption indicators, this potential is assessed, taking into consideration gas fueled engines associated with absorption cooling systems. A potential figure of approximately 500 MWe was obtained, whose effective implementation runs up against the obstacles inherent to Brazil's hospital sector, listed at the end of this paper. Consequently, some actions are proposed for surmounting these barriers
[en] This study aims to quantify the environmentally sustainable and economically feasible potentials of agricultural and agro-industrial residues to generate electricity via direct combustion in centralised power plants in Brazil. Further, the energy savings and greenhouse gas (GHG) reduction potential of replacing natural gas-based electricity by bioenergy have been assessed. To this end, a methodology has been developed based on an integrated evaluation, incorporating statistical and geographical information system (GIS)-based analysis, and a life-cycle-assessment approach. Results reveal that the environmentally sustainable generation potential is nearly 141 TWh/year, mainly concentrated in the South, Southeast, and Midwest regions of the country. Sugarcane, soybean and maize crop residues are the major feedstocks for available bioenergy. On the other hand, the economic potential is far lower, accounting to 39 TWh/year. The total GHG mitigation is nearly 18 million tonne CO2e and could reach 64 million tonne CO2e yearly, if the technical potential is considered. The gap between technical and economic potentials implies that constraints to bioenergy are not related to a lack of resources, but rather associated to economic, logistical, regulatory and political barriers. - Highlights: • Methodology to estimate technical, sustainable and economic potentials of bioenergy. • Mapping agricultural and agro-industrial residues per municipality at a country level. • Major potential comes from sugarcane, soybean and maize crops. • Economic potential accounts for about 1/3 of electricity consumption in Brazil in 2010.
[en] This study evaluates scenarios for the oil production in Peru applying a Hubbert model. Two scenarios for the estimated ultimate recovery (EUR) were proposed: the first, in which low investments in E&P and social and environmental barriers undermine the development of oil resources beyond the limits characterized as 2P; the second, more optimistic, in which current exploratory and production areas in Amazonia and low-explored Offshore-Shelf basins are developed, thus, increasing EUR to 3P reserves plus contingent resources. Findings show that oil production in Peru has not followed a Single-Hubbert pattern, except for the area with more drilling activity and the highest accumulated production in the Northwest coast. Actually, institutional and regulation changes and less-attractive periods for operators due to poor results in oil discoveries explain why a multi-Hubbert approach better depicted the oil production in Peru. Peru has the potential to achieve a second peak of 274 kbpd of crude oil, overcoming the peak of 195 kbpd, reached in 1982. However, most of the remaining production would be located in Amazonia, where social and environmental issues pose critical challenges. - Highlights: • Two scenarios of estimated ultimately recoverable resources were simulated. • A multi-cycle Hubbert approach better depicted the case of oil production in Peru. • Pipelines expansion and institutional and regulation changes explain this multi-cyle. • Institutional capacity and socio-environmental risks are barriers to oil activities
[en] Carbon capture and storage (CCS) is an effective technology for the mitigation of greenhouse gas emissions from large-scale fossil fuel use. Nonetheless, it is not yet commercially viable on a large scale, and its inclusion into countries' energy planning agendas depends on realistic assessments of its emission reduction benefits. The use of CCS leads to energy penalties resulting from direct consumption of additional energy, and results in indirect CO2 equivalent emissions outside plant boundaries, due to both energy consumption and leakages. Accounting for these emissions allows for an evaluation of the mitigation benefits of CCS. This study performs a life-cycle assessment (LCA), with and without CCS, for a coal-fired power plant located in Brazil. Findings show that when indirect emissions are taken into account, a plant which captures 90% of its CO2 will have its CO2 equivalent emissions capture potential, based on a global warming potential metric with a 100-year time horizon, reduced to 72%. The advantage of the use of carbon capture towards climate change mitigation is reduced mainly as a result of an increase in CH4 emissions, significant in the coal-mining stage, an effect which is only taken into account when a LCA is performed. - Highlights: • A life-cycle assessment for a coal-fired power plant was performed. • Two cases are compared, with and without CO2 capture. • 90% capture potential is reduced to 72% due to indirect emissions. • LCA brings out relative importance of CH4 emissions in coal mining stage. • Implications for emission reduction and climate change mitigation policies
[en] Over the past decades many countries have reformed their infrastructure industries. Although these reforms have been broadly similar for the most part, aiming at introducing competition in potentially competitive segments, the contexts in which they have been carried out differ. This is due to the past regulatory experience in each country, the maturity of the industry and/or the number of agents when the reform process started. The Brazilian natural gas reform stands out due to the country's singular conditions. The development of the natural gas industry in Brazil was grounded on stepping up supplies through integration with neighboring nations (particularly Bolivia) and establishing a competitive environment by lowering the barriers hampering the arrival of new investors. However, natural gas is located at the crossroads of two main energy chains: oil and hydroelectricity. This article analyzes the Brazilian natural gas reform, and extracts lessons from this process. The low capillarity of transportation and distribution systems continues to be the main bottleneck of the country's natural gas industry. The challenges of the new legal framework are to encourage investments in networks and guarantee supply, to allow the industry to consolidate and mature, against a backdrop of rapid changes in the world market. (author)