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  • 1.
    Dreier, Dennis
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Khatiwada, Dilip
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Fonseca, K. V. O.
    Nieweglowski, R.
    Schepanski, R.
    Well-to-Wheel analysis of fossil energy use and greenhouse gas emissions for conventional, hybrid-electric and plug-in hybrid-electric city buses in the BRT system in Curitiba, Brazil2018In: Transportation Research Part D: Transport and Environment, ISSN 1361-9209, E-ISSN 1879-2340, Vol. 58, p. 122-138Article in journal (Refereed)
    Abstract [en]

    This study estimates Well-to-Wheel (WTW) fossil energy use and greenhouse gas (GHG) emissions for six types of city buses with conventional, hybrid-electric and plug-in hybrid-electric powertrains, including two-axle, articulated and bi-articulated chassis in the BRT (Bus Rapid Transit) system in Curitiba, Brazil. Particular emphasis is put on the operation phase (Tank-to-Wheel, TTW) of the city buses using the Advanced Vehicle Simulator (ADVISOR). The simulations are based on real-world driving patterns collected from Curitiba, comprising 42 driving cycles that represent city bus operation on seven BRT routes with six operation times for each. Hybrid-electric and plug-in hybrid-electric two-axle city buses use 30% and 75% less WTW fossil energy per distance compared to a conventional two-axle city bus (19.46 MJfossil,WTW/km). This gives an absolute reduction of 1115 gCO2e,WTW/km in WTW GHG emissions when operating a plug-in hybrid-electric city bus instead of a conventional two-axle city bus (1539 gCO2e,WTW/km). However, a conventional bi-articulated city bus can be environment-friendlier than hybrid-electric city buses in terms of WTW fossil energy use and WTW GHG emissions per passenger-distance, if its passenger capacity is sufficiently utilised. Nonetheless, the plug-in hybrid-electric city bus remains the most energy-efficient and less polluting option. Hybrid-electric and plug-in hybrid-electric powertrains offer the possibility to achieve much higher levels of decarbonisation in the BRT system in Curitiba than the blending mandate of 7%vol biodiesel into diesel implemented in Brazil in 2016. In addition, the simulations show that TTW energy use can considerably vary by up to 77% between different operation times, BRT routes and types of city buses. In conclusion, advanced powertrains and large passenger capacity utilisation can promote sustainability in Curitiba's BRT system. The results of this analysis provide important insights for decision makers both in Curitiba and other cities with similar conditions.

  • 2.
    Dreier, Dennis
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khatiwada, Dilip
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fonseca, Keiko V. O.
    Federal University of Technology – Paraná (UTFPR), Curitiba, Brazil.
    Nieweglowski, Rafael
    Volvo Bus Corporation, Curitiba, Brazil.
    Schepanski, Renan
    Volvo Bus Corporation, Curitiba, Brazil.
    The influence of passenger load, driving cycle, fuel price and different types of buses on the cost of transport service in the BRT system in Curitiba, Brazil2018In: Transportation, ISSN 0049-4488, p. 1-48Article in journal (Refereed)
    Abstract [en]

    This study analyses the influence of passenger load, driving cycle, fuel price and four different types of buses on the cost of transport service for one bus rapid transit (BRT) route in Curitiba, Brazil. First, the energy use is estimated for different passenger loads and driving cycles for a conventional bi-articulated bus (ConvBi), a hybrid-electric two-axle bus (HybTw), a hybrid-electric articulated bus (HybAr) and a plug-in hybrid-electric two-axle bus (PlugTw). Then, the fuel cost and uncertainty are estimated considering the fuel price trends in the past. Based on this and additional cost data, replacement scenarios for the currently operated ConvBi fleet are determined using a techno-economic optimisation model. The lowest fuel cost ranges for the passenger load are estimated for PlugTw amounting to (0.198–0.289) USD/km, followed by (0.255–0.315) USD/km for HybTw, (0.298–0.375) USD/km for HybAr and (0.552–0.809) USD/km for ConvBi. In contrast, the coefficient of variation (Cv'>C v  Cv) of the combined standard uncertainty is the highest for PlugTw (Cv'>C v  Cv: 15–17%) due to stronger sensitivity to varying bus driver behaviour, whereas it is the least for ConvBi (Cv'>C v  Cv: 8%). The scenario analysis shows that a complete replacement of the ConvBi fleet leads to considerable higher cost of transport service on the BRT route, amounting to an increase by 64% to 139%, depending on the bus fleet composition. Meanwhile, the service quality is improved resulting in 42% up to 64% less waiting time for passengers at a bus stop.

  • 3.
    Harahap, Fumi
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Leduc, Sylvain
    International Institute for Applied Systems Analysis (IIASA).
    Sennai, Mesfun
    International Institute for Applied Systems Analysis (IIASA).
    Khatiwada, Dilip
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Kraxner, Florian
    International Institute for Applied Systems Analysis (IIASA).
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Opportunities to Optimize the Palm Oil Supply Chain in Sumatra, Indonesia2019In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 3, article id 420Article in journal (Refereed)
    Abstract [en]

    Significant amounts of biomass residues were generated in Indonesia. While untreated, residues emit greenhouse gases during the decomposition process. On the other hand, if efficiently utilized, these residues could be used to produce value-added products. This study investigates opportunities for harnessing the full potential of palm oil residues (i.e., empty fruit bunches, kernel shells, fiber, and mill effluent). As far as we are aware, the study is the first attempt to model the palm oil supply chain in a geographically explicit way while considering regional infrastructures in Sumatra Island, Indonesia. The BeWhere model, a mixed integer linear programming model for energy system optimization, was used to assess the costs and benefits of optimizing the regional palm oil supply chain. Different scenarios were investigated, considering current policies and new practices leading to improved yields in small-scale plantations and power grid connectivity. The study shows that a more efficient palm oil supply chain can pave the way for the country to meet up to 50% of its national bioenergy targets by 2025, and emission reductions of up to 40 MtCO2eq/year. As much as 50% of the electricity demand in Sumatra could be met if residues are efficiently used and grid connections are available. We recommend that system improvements be done in stages. In the short to medium term, improving the smallholder plantation yield is the most optimal way to maximize regional economic gains from the palm oil industry. In the medium to long term, improving electricity grid connection to palm oil mills could bring higher economic value as excess electricity is commercialized.

  • 4.
    Khatiwada, Dilip
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Palmén, Carl
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Evaluating the palm oil demand in Indonesia: Production trends, yields, and emerging issues2018In: Biofuels, ISSN 1759-7269, E-ISSN 1759-7277Article in journal (Refereed)
    Abstract [en]

    This paper investigates the development of domestic and international demand for Indonesian palm oil, in line with national biofuel mandates and established export markets. Domestic demand for palm oil for (i) achieving biodiesel targets and (ii) meeting food and industrial uses reaches 20 million tonnes by 2025, equivalent to 61% of Indonesian production in 2014. Thus, it is possible for Indonesia to be self-sufficient, reaching the biodiesel targets without increasing plantation areas. However, to meet both domestic and international demand, a total 51 million tonnes of crude palm oil will be needed in 2025. This requires additional land up to 6 million hectares with current yields. The expansion of oil palm plantations in Indonesia has led to debates related to deforestation, threatened biodiversity, and greenhouse gas emissions. We show that increasing agricultural yields could serve the purpose, benefiting biodiesel production while reducing the need for new land. Therefore, we recommend that the ambitious Indonesian biodiesel mandates are pursued in combination with a strategy for increased productivity in palm oil production, utilization of degraded land to contain greenhouse gas emissions, and use of palm oil biomass residues for energy production.

  • 5.
    Khatiwada, Dilip
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Scheer, Jannik
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Egeskog, Ylva
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Analyzing the lifecycle energy and greenhouse gas (GHG) balances of palm oil biodiesel production in Indonesia2016In: 15th World Renewable Energy Congress, 2016Conference paper (Refereed)
    Abstract [en]

    This study performs sustainability analysis of palm oil biodiesel production systems in Indonesia. Life Cycle Assessment (LCA) approach is used to evaluate the net GHG emissions (climate change impact) and energy inputs (resource consumption) in the entire production chain. The main aim of the study is to investigate the energy and environmental aspects of the palm oil biodiesel production chain. The worthiness of biodiesel production and use in terms of GHG emissions is compared with conventional diesel. The system boundary includes the mass and energy flows during the cultivation, harvesting, palm oil milling, and bio-refining phases. Energy inputs and emissions due to agricultural activities such land preparation, seedling, application of fertilizers/chemicals, and planting are considered in the analysis. The scope of the study also includes collection and transport of palm oil feedstock, fresh fruit brunch (FFB) and crude palm oil (CPO) for biodiesel production. Assessment of climate change impact is also performed when it comes to improvements of agricultural practices and alternation of soil carbon stocks due to land use change.

    The study examines the utilization of co-products (e.g. kernel oil, glycerol), palm oil residues, and waste water (effluents) generated during the palm biodiesel production system. Palm kernel and glycerol are important commodities/products which have high market values. The use of biomass residues (e.g. fibres and shells) for energy production in efficient cogeneration, and different waste management options for the treatment of palm oil milling effluent (POME) are also explored. Sensitivity analysis is performed for the most influencing parameters such as palm oil yield, the rate of fertilizer application, plant conversion efficiencies while determining the environmental and energy gains. Since the palm oil biodiesel production systems involve multiple co-products and services, it is of utmost importance to use appropriate allocation methods in order to divide environmental burdens and resource inputs. We use allocation by energy content and economic values, and system expansion considering the substitution of fossil based power by bioelectricity derived from biomass cogeneration plants and/or electricity generation using biogas produced from POME treatment. The study finds that bioelectricity generation from surplus biomass residues and biogas from POME, and their use for fossil fuel substitution can significantly help improve energy and environmental gains. The study also compares important results with other relevant international LCA studies and discusses issues related to land use on climate change impact. Recommendations are made for the appropriate utilization of palm oil, its co-products, and residues for the both energy and climate benefits.  

  • 6.
    Silveira, Semida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Harahap, Fumi
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Khatiwada, Dilip
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Sustainable Bioenergy Development in Indonesia - Summary for Policy Makers2018Report (Other academic)
  • 7.
    Silveira, Semida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Khatiwada, Dilip
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Leduc, S.
    Kraxner, F.
    Venkata, B. K.
    Tilvikine, V.
    Gaubyte, V.
    Romagnoli, F.
    Tauraite, E.
    Kundas, S.
    Blumberga, D.
    Peterson, K.
    Utsar, K.
    Vigants, E.
    Kalinichenko, A.
    Opportunities for bioenergy in the Baltic Sea Region2017In: International Scientific Conference “Environmental and Climate Technologies”, CONECT 2017, 10-12 May 2017, Riga, Latvia, Elsevier, 2017, Vol. 128, p. 157-164Conference paper (Refereed)
    Abstract [en]

    Security of energy supply, promotion of the bio-economy, nutrient recycling, and innovation are prioritized policy areas in the EU Strategy for the Baltic Sea Region (EUBSR). The Baltic Sea Region (BSR) has a great bioenergy potential worth exploring in this context. This paper explores the state-of-art of bioenergy systems and synergies with eco-systems services in the BSR region in the context of developing the region's bio-economy. In this brief assessment, we consider 8 countries (i.e. Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Denmark, and Belarus) in the region. While the production and use of modern bioenergy can help reduce greenhouse gas (GHG) emissions, promote energy security, diversify energy resources, and contribute to a successful circular economy and rural development, it is important to find a balance between the exploration of resources and the management of eco-systems services. In addition, both climate change vulnerability and bioenergy production may affect the environment and the capacity of the BSR to deliver ecosystem services (ESS). We recommend integrated strategies for optimal use of bioresources in the region. Bioeconomy can be realized by innovative approaches, establishing cross-cutting institutional and policy linkages for increased prosperity and green growth in the Baltic Sea Region.

1 - 7 of 7
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