| 1. |
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| 2. |
- Beiron, Johanna, 1992, et al.
(författare)
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Combined heat and power operational modes for increased product flexibility in a waste incineration plant
- 2020
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Ingår i: Energy. - : Elsevier BV. - 0360-5442. ; 202
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Tidskriftsartikel (refereegranskat)abstract
- The expected strong expansion of wind power may cause challenges for the electricity system in terms of grid stability, power balance, and increased electricity price volatility. This paper analyses how the new market conditions impact the operational pattern and revenue of a combined heat and power (CHP) plant. The work focuses on product flexibility that enables varied ratios between products; and thermal flexibility, to shift load in time given the differing timescales of heat and power demand. Product flexibility is given by five operational modes: conventional CHP, heat-only, CHP plus frequency response, condensing, and condensing plus frequency response. Optimization and process modeling are combined to study the plant dispatch in current and future electricity market scenarios and with thermal flexibility. The results indicate that load-shifting of heat generation together with condensing operation can increase revenue up to 4.5 M€ and plant utilization up to 100% for a 50 MWel waste-fired plant; but requires a thermal energy storage to meet hourly heat demand. The electricity price profile impacts both the revenue and operational patterns, with low-price periods favoring increased heat generation and frequency response delivery. High average electricity price and price volatility results in increased profitability of product and thermal flexibility.
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| 3. |
- Beiron, Johanna, 1992, et al.
(författare)
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Flexible operation of a combined cycle cogeneration plant - A techno-economic assessment
- 2020
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Ingår i: Applied Energy. - : Elsevier BV. - 1872-9118 .- 0306-2619. ; 278
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Tidskriftsartikel (refereegranskat)abstract
- The need for flexibility in combined heat and power (CHP) plants is expected to increase due to the strong expansion of wind power in electricity systems. Cost-effective strategies to enhance the flexibility of CHP operation are therefore needed. This paper analyzes three types of flexibility measures for a combined cycle CHP plant and their relative impact on the plant operation and revenue. The types of flexibility are: operational flexibility of the fuel conversion system, product flexibility with variable plant product ratios (heat/electricity/primary frequency response), and thermal flexibility in a district heating network. A modeling framework consisting of steady-state and dynamic process simulation models and optimization model is developed to combine static, dynamic, technical and economic perspectives on flexibility. A reference plant serves as a basis for the process model development and validation, and an energy system model provides input profiles for future electricity price scenarios. The results indicate that product flexibility and thermal flexibility have the highest value for the cogeneration plant (up to 16.5 M€ increased revenue for a 250 MWel plant), while operational flexibility (ramp rate) has a comparatively small impact (<1.4 M€). A wide load span and plant versatility, e.g. electricity and heat generating potential between 0 and 139% of nominal capacity, is beneficial in future energy system contexts, but has a marginal value in the current system. Electricity price volatility is a main driver that increases the value of flexibility and promotes operating strategies that follow the electricity price profile rather than the heat demand.
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| 4. |
- Biermann, Max, 1989, et al.
(författare)
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Carbon Allocation in Multi-Product Steel Mills That Co‐process Biogenic and Fossil Feedstocks and Adopt Carbon Capture Utilization and Storage Technologies
- 2020
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Ingår i: Frontiers in Chemical Engineering. - : Frontiers Media SA. - 2673-2718. ; 2
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Tidskriftsartikel (refereegranskat)abstract
- This work investigates the effects of carbon allocation on the emission intensities of low-carbon products cogenerated in facilities that co‐process biogenic and fossil feedstocks and apply the carbon capture utilization and storage technology. Thus, these plants simultaneously sequester CO2 and synthesize fuels or chemicals. We consider an integrated steel mill that injects biomass into the blast furnace, captures CO2 for storage, and ferments CO into ethanol from the blast furnace gas. We examine two schemes to allocate the CO2 emissions avoided [due to the renewable feedstock share (biomass) and CO2 capture and storage (CCS)] to the products of steel, ethanol, and electricity (generated through the combustion of steel mill waste gases): 1) allocation by (carbon) mass, which represents actual carbon flows, and 2) a free-choice attribution that maximizes the renewable content allocated to electricity and ethanol. With respect to the chosen assumptions on process performance and heat integration, we find that allocation by mass favors steel and is unlikely to yield an ethanol product that fulfills the Renewable Energy Directive (RED) biofuel criterion (65% emission reduction relative to a fossil comparator), even when using renewable electricity and applying CCS to the blast furnace gas prior to CO conversion into ethanol and electricity. In contrast, attribution fulfills the criterion and yields bioethanol for electricity grid intensities 2/kWhel without CCS and yields bioethanol for grid intensities up to 800 gCO2/kWhel with CCS. The overall emissions savings are up to 27 and 47% in the near-term and long-term future, respectively. The choice of the allocation scheme greatly affects the emissions intensities of cogenerated products. Thus, the set of valid allocation schemes determines the extent of flexibility that manufacturers have in producing low-carbon products, which is relevant for industries whose product target sectors that value emissions differently. We recommend that policymakers consider the emerging relevance of co‐processing in nonrefining facilities. Provided there is no double-accounting of emissions, policies should contain a reasonable degree of freedom in the allocation of emissions savings to low-carbon products, so as to promote the sale of these savings, thereby making investments in mitigation technologies more attractive to stakeholders.
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| 5. |
- Biermann, Max, 1989, et al.
(författare)
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Efficient utilization of industrial excess heat for carbon capture and district heating
- 2020
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Carbon capture and storage (CCS) from fossil and biogenic (BECCS) emission sources is necessary to limit global warming to well below 2°C. The EU as well as Swedish national agencies emphasize the importance of CCS for emission intensive industries. However, the cost of implementing CCS is currently still higher than the cost of emitting CO2 via the EU ETS, for example. To incentivize rapid deployment of CCS, the concept of partial capture has been suggested, i.e. capturing only a fraction of the site emissions to reduce capture cost. Several studies have found that the utilization of excess heat from industrial processes could significantly reduce the capture cost as the heat required (~120°C) may be available in significant quantities. However, available excess heat will not be sufficient to power full capture at most industrial sites. In Sweden, many industries utilize all or part of their excess heat in heat recovery units or in combined heat and power (CHP) plants to produce electricity and deliver heat to municipal district heating (MDH) systems. A broad implementation of CCS will, thus, effect the availability of excess heat for industrial heat and power generation. The future product portfolio of industrial processes with excess heat export and CHP plants can therefore be expected to include not only heat and power production, but also climate services (CCS/BECCS) and grid services (frequency regulation due to intermittent renewables). The aim of this work is to assess partial capture at sites that have access to low-value excess heat to power the capture process, whilst considering competition from using the excess heat for MDH delivery. The work is based on process modelling and cost estimation of CO2 capture processes using amine absorption for two illustrative case studies, a refinery and a steel mill, which both currently use excess heat for MDH. The main focus is on investigating how seasonal variations in the availability of excess heat as well as the demand of district heating impact cost-efficient design and operation of partial capture at industrial sites. A challenge when utilizing excess heat in connection to a process connected to a district heating system is that the heat source which can be used to power part of the capture process will exhibit seasonal availability, and thus may inflict extra cost for the CCS plant not running at full load, and therefore may counteract the economic motivation for partial capture. To prevent this, heat integration between CCS and municipal district heating is investigated, for example by utilizing heat from the CO2 compression so that low-pressure steam is released from MDH to provide heat to capture CO2 whilst maintaining MDH supply. The design of the amine absorption capture process will have to handle significant load changes and still maintain high separation efficiency within hydrodynamic boundaries of the absorber and stripper columns. The cost of such operation will depend on the solvent circulation flows, the number of absorber columns (including packing and liquid collectors/distributors) and capacity of solvent buffer tanks for storing unused solvent during the winter season. Assuming that a constant amount of CO2 is avoided, the avoidance cost of CCS based on excess heat with seasonal heat load variations is compared to the avoidance cost of CCS based on the use of external fuel to achieve a constant heat load to the reboiler.
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| 6. |
- Holmér, Petra, 1992, et al.
(författare)
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Impacts of thermal energy storage on the management of variable demand and production in electricity and district heating systems: a Swedish case study
- 2020
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Ingår i: International Journal of Sustainable Energy. - : Informa UK Limited. - 1478-646X .- 1478-6451. ; 39:5, s. 446-464
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates how thermal energy storage (TES) influences the cost-optimal investment and operation of electricity and district heating (DH) systems in different scenarios. Greenfield energy system modelling for Year 2050 with a high time resolution shows that sensible TES strategies have a strong impact on the composition and operation of the DH system in all investigated scenarios. The introduction of TES displaces to a significant extent the heat-only boilers in all scenarios and can promote solar heating in small DH networks. The modelling shows that TES also promotes the use of power-to-heat processes and enables combined heat and power plants to increase full-load hours, with simultaneous adaptation to the variable production in the electricity system. A major benefit derived from TES is the ability to respond to rapid variations in the electricity system. Thus, the pit and tank storage systems with higher (dis)charging capacities are preferred over borehole storage.
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| 7. |
- Johnsson, Filip, 1960, et al.
(författare)
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Marginal Abatement Cost Curve of Industrial CO 2 Capture and Storage – A Swedish Case Study
- 2020
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Ingår i: Frontiers in Energy Research. - : Frontiers Media SA. - 2296-598X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Carbon capture and storage (CCS) is expected to play a key role to achieve deep emission cuts in the energy intensive industry sector. The implementation of carbon capture comes with a considerable investment cost and a significant effect on the plants operating cost, which both depend on site conditions, mainly due to differences in flue gas flow and composition and depending on the availability of excess heat that can be utilized to power the capture unit. In this study we map the costs required to install and operate amine-based post-combustion CO2 capture at all manufacturing plants in Sweden with annual emissions of 500 kt CO2 or more, of both fossil and of biogenic origin, of which there are 28 plants (including a petrochemical site, refineries, iron and steel plants, cement plants and pulp and paper mills). The work considers differences in the investment required as well as differences in potential for using excess heat to cover the steam demand of the capture process. We present the resulting total CO2 capture costs in the form of a marginal abatement cost curve (MACC) for the emission sources investigated. Cost estimations for a transport and storage system are also indicated. The MACC shows that CO2 capture applied to 28 industrial units capture CO2 emissions corresponding to more than 50% of Swedish total CO2 emissions (from all sectors) at a cost ranging from around 40 €/t CO2 to 110 €/t CO2, depending on emission source. Partial capture from the most suited sites may reduce capture cost and, thus, may serve as a low-cost option for introducing CCS. The cost for transport and storage will add some 25 to 40 €/t CO2, depending on location and type of transportation infrastructure.
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| 8. |
- Johnsson, Filip, 1960, et al.
(författare)
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The framing of a sustainable development goals assessment in decarbonizing the construction industry – Avoiding “Greenwashing”
- 2020
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Ingår i: Renewable and Sustainable Energy Reviews. - : Elsevier BV. - 1879-0690 .- 1364-0321. ; 131
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this paper is to contribute to the establishment of a robust framework for the assessment of Sustainable Development Goals (SDGs) in businesses, using the construction industry as an example and with the primary focus on combating climate change (SDG 13). We provide a critical analysis of a selection of relatively widely used SDG impact assessment tools, combined with a case study from the construction industry to explore how a meaningful SDG assessment can be framed with linkages between SDG 13 and other related SDGs. Our analysis points towards the importance of framing SDG assessments in a way that discourages “Greenwashing”. Any SDG assessment that relates to climate targets in line with the Paris Agreement should identify the processes and activities that can be expected to be particularly challenging in terms of their abatement. In our road construction work case, we identify four such hard-to-abate activities: 1) introducing biomass for renewable transportation fuels for use in construction equipment and heavy transport; 2) electrification of transport and industrial processes; 3) substitution as part of transitioning from fossil fuel use; and 4) applying carbon capture and storage technologies in the production of basic materials, such as cement and steel. The approach applied will avoid that businesses only focus on SDGs in situations where they are already performing well or can apply low-cost measures or that they only relate to the part of the supply chain that pertains to their own business (Scope 1 emissions). For an SDG assessment to provide basis for informed decisions regarding real change towards more sustainable and equitable corporate practices it should: (i) identify and include concrete measures to align with the terms of the Paris Agreement; (ii) include relevant value chains; and (iii) consider both the short-term and long-term effects of strategic choices.
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| 9. |
- Karlsson, Ida, 1980, et al.
(författare)
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Reaching net-zero carbon emissions in construction supply chains - Analysis of a Swedish road construction project
- 2020
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Ingår i: Renewable & Sustainable Energy Reviews. - : Elsevier BV. - 1364-0321 .- 1879-0690. ; 120
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Tidskriftsartikel (refereegranskat)abstract
- Recent estimates suggest that the construction sector accounts for approximately one quarter of global CO2 emissions. This paper assesses the potential for reducing the climate impact of road construction. The study is structured as a participatory integrated assessment with involvement from key stakeholders in the supply chain, supported by energy and material flow mapping, an extensive literature review and a scenario analysis. The results indicate that it is technically possible to halve road construction CO2 emissions with today's best available technologies and practices, to abate more than three quarters of the emissions by 2030 and achieve close to net zero emissions by 2045. Realising the current potential would rely on sufficient availability of sustainably produced second-generation biofuels, indicating a need to speed up the implementation of alternative abatement measures, including optimization of material use and mass handling requirements, increased recycling of steel, asphalt and aggregates and enhanced use of alternative binders in concrete. Policy measures and procurement strategies should be aligned to support these measures with a clear supply chain focus. For deep decarbonization several key opportunities and obstacles for realisation of breakthrough technologies for basic industry are highlighted including electrification and carbon capture for steel and cement, and hybridisation and electrification for heavy transport and construction equipment. There is a clear need to prepare for deeper abatement and associated transformative shifts already now and to carefully consider the pathway of getting there while avoiding pitfalls along the way, such as overreliance on biofuels or cost optimizations which cannot be scaled up to the levels required.
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| 10. |
- Karlsson, Ida, 1980, et al.
(författare)
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Roadmap for climate transition of the building and construction industry – a supply chain analysis including primary production of steel and cement
- 2020
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Ingår i: Eceee Industrial Summer Study Proceedings. - 2001-7987 .- 2001-7979. ; 2020-September, s. 67-77
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Konferensbidrag (refereegranskat)abstract
- Sweden has, in line with the Paris agreement, committed to reducing greenhouse gas emissions to net-zero by 2045. Emissions arising from manufacturing, transporting and processing of construction materials to buildings and infrastructure account for approximately one fifth of Sweden’s annual CO2 emissions. This work provides a roadmap with an analysis of different pathways of technological developments in the supply chains of the buildings and construction industry, including primary production of steel and cement. By matching short-term and long-term goals with specific technology solutions, these pathways make it possible to identify key decision points and potential synergies, competing goals and lock-in effects. The analysis combines quantitative analysis methods, including scenarios and stylized models, with participatory processes involving relevant stakeholders in the assessment process. The roadmap outline material and energy flows associated with different technical and strategical choices and explores interlink-ages and interactions across sectors. The results show that it is possible to reduce CO2 emissions associated with construction of buildings and transport infrastructure by 50 % to 2030 and reach close to zero emissions by 2045, while indicating that strategic choices with respect to process technologies, energy carriers and the availability of biofuels, CCS and zero CO2 electricity may have different implications on energy use and CO2 emissions over time. The results also illustrate the importance of intensifying efforts to identify and manage both soft (organisation, knowledge sharing, competence) and hard (technology and costs) barriers and the importance of both acting now by implementing available measures (e.g. material efficiency and material/fuel substitution measures) and actively planning for long-term measures (low-CO2 steel or cement). Unlocking the full potential of the range of emission abatement measures will require not only technological innovation but also innovations in the policy arena and efforts to develop new ways of cooperating, coordinating and sharing information between actors.
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