| 1. |
- Broberg, Sarah, 1983-, et al.
(författare)
-
Integrated Algae Cultivation for Biofuels Production in Industrial Clusters
- 2011
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Declining fossil resources and the issue of climate change caused by anthropogenic emissions of greenhouse gases make global action towards a more sustainable society inevitable. The EU decided in 2007 that 20 % of the union´s energy use should origin from renewable resources by the year 2020. One way of achieving this goal is to increase the utilisation of biofuels. Today 2nd generation biofuels are being developed. They are seen as a more sustainable solution than 1st generation biofuels since they have a higher area efficiency (more fuel produced per area) and the biomass can be cultivated at land which is not suitable for food crops. One of these 2nd generation biofuels are fuels derived from microalgae. In this study a thorough literature survey has been conducted in order to assess the State-of-the-Art in algae biofuels production. The literature review showed the importance of a supplementary function in conjunction with algae cultivation and therefore algae cultivation for municipal wastewater treatment and capturing CO2 emissions from industry was included in the study. It was assumed that all the wastewater of the city of Gothenburg, Sweden, was treated by algae cultivation. A computer model of the whole production process has been developed, covering; algae cultivation in conjunction with wastewater treatment, algae harvesting and biofuels production. Two different cases are modelled; a first case including combined biodiesel and biogas production, and a second case investigating only biogas production. Both cases have been evaluated in terms of product outputs, CO2 emissions savings and compared to each other in an economic sense. Utilising the nutrients in the wastewater of Gothenburg it is possible to cultivate 29 ktalgae/year. In the biogas case it is possible to produce 205 GWhbiogas/year. The biogas/biodiesel case showed a production potential of 63 GWhbiodiesel/year and 182 GWhbiogas/year. There is a deficit of carbon in the wastewater, hence CO2 is injected as flue gases from industrial sources. The biodiesel/biogas case showed an industrial CO2 sequestration capacity of 24 ktCO2/year while in the biogas case 22.6 ktCO2/year, could be captured. Estimating the total CO2 emissions savings showed 46 ktCO2/year in the biodiesel/biogas case and 38 ktCO2/year for the biogas case. The importance of including wastewater treatment in the process was confirmed, as it contributes with 13.7 ktCO2/year to the total CO2 emissions savings. Economic comparison of the two cases showed that biodiesel in conjunction with biogas production is advantageous compared to only biogas production. This is mainly due to the higher overall fuel yield and the high willingness to pay for biodiesel. The total incomes from biodiesel/biogas sales were calculated to 221 million SEK/year and 193 million SEK/year for biogas. It was found that the higher incomes from biodiesel/biogas sales repay the increased investment for the biodiesel process in approximately 3 years.
|
|
| 2. |
- Andersson, Viktor, 1983, et al.
(författare)
-
Dubbel energivinst med alger som biobränsle
- 2013
-
Ingår i: Energimagasinet.
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Idag kan produktionen av biobränsle påverka livsmedelsförsörjningen negativt. Istället för att biobränsleproduktion ska konkurrera med produktion av livsmedel kan en hittills outnyttjad resurs - kommunalt avloppsvatten - användas för produktion av alger som i sin tur kan användas till biogas och biodiesel. Ny forskning visar på denna potential.
|
|
| 3. |
- Andersson, Viktor, 1983, et al.
(författare)
-
Algae-based biofuel production as part of an industrial cluster
- 2014
-
Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 1873-2909 .- 0961-9534. ; 71, s. 113-124
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a study on the production of biofuels from algae cultivated in municipal wastewater in Gothenburg, Sweden. A possible biorefinery concept is studied based on two cases; Case A) combined biodiesel and biogas production, and Case B) only biogas production. The cases are compared in terms of product outputs and impact on global CO2 emissions mitigation. The area efficiency of the algae-based biofuels is also compared with other biofuel production routes. The study investigates the collaboration between an algae cultivation, biofuel production processes, a wastewater treatment plant and an industrial cluster for the purpose of utilizing material flows and industrial excess heat between the actors. This collaboration provides the opportunity to reduce the CO2 emissions from the process compared to a stand-alone operation. The results show that Case A is advantageous to Case B with respect to all studied factors. It is found that the algae-based biofuel production routes investigated in this study has higher area efficiency than other biofuel production routes. The amount of algae-based biofuel possible to produce corresponds to 31 MWfuel for Case A and 26 MWfuel in Case B.
|
|
| 4. |
- Andersson, Viktor, 1983, et al.
(författare)
-
Integrated Algae Cultivation for Municipal Wastewater Treatment and Biofuels Production in Industrial Clusters
- 2012
-
Ingår i: World Renewable Energy Forum, WREF 2012. - 9781622760923 ; 1, s. 684-691
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a case study on biofuels production from microalgae cultivated in municipal wastewater in Gothenburg, Sweden. A) Combined biodiesel and biogas production and B) only biogas production, are compared in terms of product outputs, impact on global CO2 emissions reduction and economic performance. Land-use efficiency of biofuels from microalgae was compared with other biofuel production routes. The biofuel production process is assumed to be integrated with a wastewater treatment plant and an industrial cluster, providing the opportunity to reduce the CO2 emissions of the process compared to stand-alone operation.The results show that case A is advantageous in terms of all the studied factors. A higher area efficiency of algae biofuels production routes compared to other biofuel production routes was shown. Nutrient availability in municipal wastewater is shown to be the limiting factor regarding product output. The competitive advantage of co-location with a wastewater treatment plant is clearly shown.
|
|
| 5. |
- Broberg Viklund, Sarah, 1983-, et al.
(författare)
-
Technologies for utilization of industrial excess heat : Potentials for energy recovery and CO2 emission reduction
- 2014
-
Ingår i: Energy Conversion and Management. - : Elsevier BV. - 0196-8904 .- 1879-2227. ; 77, s. 369-379
-
Tidskriftsartikel (refereegranskat)abstract
- Industrial excess heat is a large untapped resource, for which there is potential for external use, which would create benefits for industry and society. Use of excess heat can provide a way to reduce the use of primary energy and to contribute to global CO2 mitigation. The aim of this paper is to present different measures for the recovery and utilization of industrial excess heat and to investigate how the development of the future energy market can affect which heat utilization measure would contribute the most to global CO2 emissions mitigation. Excess heat recovery is put into a context by applying some of the excess heat recovery measures to the untapped excess heat potential in Gavleborg County in Sweden. Two different cases for excess heat recovery are studied: heat delivery to a district heating system and heat-driven electricity generation. To investigate the impact of excess heat recovery on global CO2 emissions, six consistent future energy market scenarios were used. Approximately 0.8 TWh/year of industrial excess heat in Gavleborg County is not used today. The results show that with the proposed recovery measures approximately 91 GWh/year of district heating, or 25 GWh/year of electricity, could be supplied from this heat. Electricity generation would result in reduced global CO2 emissions in all of the analyzed scenarios, while heat delivery to a DH system based on combined heat and power production from biomass would result in increased global CO2 emissions when the CO2 emission charge is low.
|
|
| 6. |
- Fernqvist, Niklas, 1973, et al.
(författare)
-
District heating as a flexibility service: Challenges in sector coupling for increased solar and wind power production in Sweden
- 2023
-
Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215 .- 1873-6777. ; 172
-
Tidskriftsartikel (refereegranskat)abstract
- With expanding solar and wind power production, the topic of flexibility services attracts increased attention in the Swedish energy system. In this context, the potentials in using thermal storage capacities in district heating (DH) systems have been brought forward, primarily by academic scholars. Using a ‘grounded’ approach, this study investigates if professionals assigned to Swedish DH companies and electricity distribution system operators utilise, or plan to utilise, DH systems as flexibility services for the electricity grid. Original data was collected through semi-structured interviews, held with fourteen individuals affiliated to different actors in the Swedish energy system. These individuals were identified as being experts, or practically engaged, in using DH utilities as flexibility services for the electricity grid. The findings show that although technologies for coupling between DH systems and the electricity grid are already in place, initiatives for using DH systems as flexibility services for the electricity system are rare in Sweden. Coupling challenges stem from ownership and operation legislation frameworks, marginal incentives and a widespread focus on firm benefits rather than energy systems benefits. Identified initiatives for using DH systems for flexibility services are primarily run on a local scale, designed and propelled by small groups of engaged individuals.
|
|
| 7. |
- Johansson, Maria, et al.
(författare)
-
Interaktioner mellan affärs-, energi- och innovationsstrategier i massa- och pappersindustrin - slutrapport
- 2020
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Samhällets omställning till en biobaserad ekonomi innebär nya möjligheter för svensk massa- och pappersindustri. Detta projekt har studerat hur massa- och pappersföretag i Sverige formulerar sina affärsstrategier i relation till krav på produktdiversifiering och förbättrad energi- och resurseffektivitet. Projektet har särskilt fokuserat på interaktioner mellan företagens affärs-, energi- och innovationsstrategier med syfte att öka kunskapen om dels företagens strategier och dels hur de tillsammans påverkar företagens möjligheter att möta de krav som ställs på branschen och, i förlängningen, deras förmåga att uppnå en hållbar och konkurrenskraftig produktion. Projektet har genomförts genom en intervjustudie med utvalda massa- och pappersföretag, en enkät till bruken i Sverige, dokumentstudier samt studier av utvalda innovationsprojekt. Studien har identifierat tre typer av affärsstrategier i branschen: bred differentiering, fokuserad differentiering samt kostnadsledarskap. De flesta studerade företag har en av de två förstnämnda strategierna. Resultaten visar att innovationsstrategierna har en tydlig relation till affärsstrategierna i det att företag som har en differentieringsstrategi strävar efter teknologiskt ledarskap eller åtminstone att vara snabba efterföljare, medan lågkostnadsproducenten har en innovationsstrategi som går ut på att följa efter senare än de andra. De studerade företagens energistrategier är mångfacetterade och kan relatera till företagets affärsstrategier på flera sätt. Energistrategin innefattar såväl aktiviteter som syftar till minskade kostnader som aktiviteter som syftar till att öka företagets intäkter. Alla företag i studien arbetar strategiskt med energi och har satt upp mål för detta arbete. Studien visar att företagen arbetar strategiskt med att minska sina energirelaterade kostnader genom energieffektivisering, energibesparing, självförsörjning av energi och byte till förnybar energi. Hälften av de studerade företagen arbetar även strategiskt med att ta fram och sälja energiprodukter för att härigenom öka sina intäkter och studien indikerar ett ökat intresse för detta. Studien har identifierat både synergier och konflikter mellan företagens innovations- och energistrategier. Synergier uppstår när energieffektiviseringar resulterar i processinnovationer (och vice versa), produktinnovationer leder till förbättrade energiprestanda eller nya biobaserade produkter ersätter fossilbaserade produkter. Samtidigt finns det även konflikter, eller trade-off, mellan innovation- och energistrategier, till exempel i form av ökad energianvändning i samband med produktionen av nya produkter. I dessa fall, är innovationens potentiella lönsamhet, eller business case, avgörande: innovationer med hög lönsamhet satsas på trots högre energianvändning.
|
|
| 8. |
- Broberg, Sarah, et al.
(författare)
-
Biogas production supported by excess heat - A systems analysis within the food industry
- 2015
-
Ingår i: Energy Conversion and Management. - : Elsevier. - 0196-8904 .- 1879-2227. ; 91, s. 249-258
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this paper was to study the effects on greenhouse gases and economics when a change is made in the use of industrial organic waste from external production and use of biogas (A) to internal production and use (B). The two different system solutions are studied through a systems analysis based on an industrial case. The baseline system (A) and a modified system (B) were compared and analysed. Studies show that industrial processes considered as integrated systems, including the exchange of resources between industries, can result in competitive advantages. This study focuses on the integration of internally produced biogas from food industry waste produced by a food company and the use of excess heat. Two alternative scenarios were studied: (1) the use of available excess heat to heat the biogas digester and (2) the use of a part of the biogas produced to heat the biogas digester. This study showed that the system solution, whereby excess heat rather than biogas is used to heat the biogas digester, was both environmentally and economically advantageous. However, the valuation of biomass affects the magnitude of the emissions reduction. Implementing this synergistic concept will contribute to the reaching of European Union climate targets. (C) 2014 Elsevier Ltd. All rights reserved.
|
|
| 9. |
- Broberg, Sarah
(författare)
-
Energy efficiency through industrial excess heat recovery-policy impacts
- 2015
-
Ingår i: Energy Efficiency. - : Springer Verlag (Germany). - 1570-646X .- 1570-6478. ; 8:1, s. 19-35
-
Tidskriftsartikel (refereegranskat)abstract
- The EU target on energy efficiency implies a 20 % reduction in the use of primary energy by implementation of energy efficiency measures. Not all potential cost-effective measures for improved energy efficiency are implemented. This energy efficiency gap is explained by market barriers. Policy instruments can be used to overcome these barriers. The target could, for example, be obtained through industrial excess heat recovery; but there is a knowledge gap on factors affecting excess heat utilization. In this study, interviews were carried out with energy managers in order to study excess heat utilization from industrys perspective. The study seeks to present how excess heat recovery can be promoted or discouraged through policy instruments, and several factors are raised in the paper. The interviews revealed that excess heat recovery is generally referred to in terms of heat deliveries to the district heating network. One may need to look for innovative recovery solutions, and policies are needed to bring these solutions into action. Due to inefficient conversion for heat-driven electricity generation, a system favoring this implementation could favor an inefficient system. Beyond external instruments, internal goals, visions, and the importance of energy as a priority were shown to be important in the work with improved energy management.
|
|
| 10. |
- Broberg, Sarah, et al.
(författare)
-
Industrial excess heat deliveries to Swedish district heating networks : drop it like it's hot
- 2012
-
Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215 .- 1873-6777. ; 51, s. 332-339
-
Tidskriftsartikel (refereegranskat)abstract
- Using industrial excess heat in District Heating (DH) networks reduces the need for primary energy and is considered efficient resource use. The conditions of Swedish DH markets are under political discussion in the Third Party Access (TPA) proposal, which would facilitate the delivery of firms' industrial excess heat to DH networks. This paper estimates and discusses the untapped potential for excess heat deliveries to DH networks and considers whether the realization of this potential would be affected by altered DH market conditions. The results identify untapped potential for industrial excess heat deliveries, and calculations based on estimated investment costs and revenues indicate that realizing the TPA proposal could enable profitable excess heat investments.
|
|
