Energies

Research

Jump to: Review

28 pages, 816 KiB

Open AccessArticle

Evaluation of Integrated Concepts with CO₂ for Heating, Cooling and Hot Water Production

by Silje Smitt, Ángel Pardiñas and Armin Hafner

Energies 2021, 14(14), 4103; https://doi.org/10.3390/en14144103 - 7 Jul 2021

Cited by 2 | Viewed by 2031

Abstract

The hotel sector is characterized by high thermal demands and a large carbon footprint, which greatly contributes to the global warming effect. Consequently, there is a need to investigate solutions that can reduce energy usage within this sector by means of environmentally friendly [...] Read more.

The hotel sector is characterized by high thermal demands and a large carbon footprint, which greatly contributes to the global warming effect. Consequently, there is a need to investigate solutions that can reduce energy usage within this sector by means of environmentally friendly and sustainable technologies. Integrated CO₂ heat pump systems for heating, cooling, and hot water production in hotels have demonstrated promising results. This paper theoretically compares the energy consumption, environmental impact, and cost of three different design concepts for integrated CO₂ units equipped with thermal storage. The main characteristics of the evaluated designs are single-stage compression, parallel compression, and ejector-supported parallel compression. Furthermore, two separate hot water charging strategies were implemented and investigated over a large span of ambient temperatures and loads. The evaluations were carried out by considering eight different European locations, ranging from Scandinavia to the Mediterranean. The results revealed that the ejector-supported parallel compression design was superior in terms of annual COP, which was found to be in the range of 4.27 to 5.01 for the Scandinavian locations and 5.03 to 5.71 for the other European locations. When accounting for investment cost and electricity prices, the payback period at the Scandinavian locations was 6.3 to 7.7 years. Payback periods of 3 and 4.5 to 7.5 were obtained for hotels located in the temperate and Mediterranean climates, respectively. The investigation also revealed that the hot water charging strategy, rather than the specific CO₂ heat pump design, is the least expensive measure to enhance performance. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

12 pages, 7199 KiB

Open AccessArticle

A Novel Iron Chloride Red-Ox Concentration Flow Cell Battery (ICFB) Concept; Power and Electrode Optimization

by Robert Bock, Björn Kleinsteinberg, Bjørn Selnes-Volseth and Odne Stokke Burheim

Energies 2021, 14(4), 1109; https://doi.org/10.3390/en14041109 - 19 Feb 2021

Cited by 2 | Viewed by 2392

Abstract

For renewable energies to succeed in replacing fossil fuels, large-scale and affordable solutions are needed for short and long-term energy storage. A potentially inexpensive approach of storing large amounts of energy is through the use of a concentration flow cell that is based [...] Read more.

For renewable energies to succeed in replacing fossil fuels, large-scale and affordable solutions are needed for short and long-term energy storage. A potentially inexpensive approach of storing large amounts of energy is through the use of a concentration flow cell that is based on cheap and abundant materials. Here, we propose to use aqueous iron chloride as a reacting solvent on carbon electrodes. We suggest to use it in a red-ox concentration flow cell with two compartments separated by a hydrocarbon-based membrane. In both compartments the red-ox couple of iron II and III reacts, oxidation at the anode and reduction at the cathode. When charging, a concentration difference between the two species grows. When discharging, this concentration difference between iron II and iron III is used to drive the reaction. In this respect it is a concentration driven flow cell redox battery using iron chloride in both solutions. Here, we investigate material combinations, power, and concentration relations. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

21 pages, 5365 KiB

Open AccessArticle

The Carbon Footprint of Electrified City Buses: A Case Study in Trondheim, Norway

by Kristoffer W. Lie, Trym A. Synnevåg, Jacob J. Lamb and Kristian M. Lien

Energies 2021, 14(3), 770; https://doi.org/10.3390/en14030770 - 1 Feb 2021

Cited by 15 | Viewed by 6894

Abstract

In August 2019, a new bus fleet of 36 electric and 58 hybrid buses were implemented in Trondheim, Norway. This paper examines the carbon footprint of electrified city buses, by addressing the achieved and potential reduction for the new bus fleet. Important aspects [...] Read more.

In August 2019, a new bus fleet of 36 electric and 58 hybrid buses were implemented in Trondheim, Norway. This paper examines the carbon footprint of electrified city buses, by addressing the achieved and potential reduction for the new bus fleet. Important aspects such as geographical location of production, charging electricity mix, and impact from production and operation on lifetime emissions, are also examined. A meta-analysis on life cycle assessment studies was undertaken to investigate greenhouse gas emissions and energy demand in different parts of bus production. This is followed by the production of a bus model using the findings and comparing electrified buses with diesel and HVO buses. The models were then used in a case study of the bus fleet in Trondheim, to understand the specific parameters affecting the carbon footprint. The results show that the overall carbon footprint has been considerably reduced (37%) by implementing biofuel and electrified buses, and that a further reduction of 52% can be achieved through full electrification. The operation emissions for the fleet were found to be 49 g CO₂-eq/person-km, which is lower than the average city bus and passenger car in Norway. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

Review

Jump to: Research

26 pages, 2845 KiB

Open AccessReview

Review of Energy Storage and Energy Management System Control Strategies in Microgrids

by Gaurav Chaudhary, Jacob J. Lamb, Odne S. Burheim and Bjørn Austbø

Energies 2021, 14(16), 4929; https://doi.org/10.3390/en14164929 - 11 Aug 2021

Cited by 60 | Viewed by 6471

Abstract

A microgrid (MG) is a discrete energy system consisting of an interconnection of distributed energy sources and loads capable of operating in parallel with or independently from the main power grid. The microgrid concept integrated with renewable energy generation and energy storage systems [...] Read more.

A microgrid (MG) is a discrete energy system consisting of an interconnection of distributed energy sources and loads capable of operating in parallel with or independently from the main power grid. The microgrid concept integrated with renewable energy generation and energy storage systems has gained significant interest recently, triggered by increasing demand for clean, efficient, secure, reliable and sustainable heat and electricity. However, the concept of efficient integration of energy storage systems faces many challenges (e.g., charging, discharging, safety, size, cost, reliability and overall management). Additionally, proper implementation and justification of these technologies in MGs cannot be done without energy management systems, which control various aspects of power management and operation of energy storage systems in microgrids. This review discusses different energy storage technologies that can have high penetration and integration in microgrids. Moreover, their working operations and characteristics are discussed. An overview of the controls of energy management systems for microgrids with distributed energy storage systems is also included in the scope of this review. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

17 pages, 2653 KiB

Open AccessReview

The Importance of Optical Fibres for Internal Temperature Sensing in Lithium-ion Batteries during Operation

by Markus S. Wahl, Lena Spitthoff, Harald I. Muri, Asanthi Jinasena, Odne S. Burheim and Jacob J. Lamb

Energies 2021, 14(12), 3617; https://doi.org/10.3390/en14123617 - 17 Jun 2021

Cited by 18 | Viewed by 4656

Abstract

Lithium-ion batteries (LiBs) are widely used as energy storage systems (ESSs). The biggest challenge they face is retaining intrinsic health under all conditions, and understanding internal thermal behaviour is crucial to this. The key concern is the potentially large temperature differences at high [...] Read more.

Lithium-ion batteries (LiBs) are widely used as energy storage systems (ESSs). The biggest challenge they face is retaining intrinsic health under all conditions, and understanding internal thermal behaviour is crucial to this. The key concern is the potentially large temperature differences at high charge/discharge rates. Excess heat created during charge/discharge will accelerate irreversible aging, eventually leading to failure. As a consequence, it is important to keep battery states within their safe operating range, which is determined by voltage, temperature, and current windows. Due to the chemically aggressive and electrically noisy environment, internal temperature measurement is difficult. As a result, non-invasive sensors must be physically stable, electromagnetic interference-resistant, and chemically inert. These characteristics are provided by fibre Bragg grating (FBG) sensors, which are also multiplexable. This review article discusses the thermal problems that arise during LiB use, as well as their significance in terms of LiB durability and protection. FBG-based sensors are described as a technology, with emphasis on their importance for direct temperature measurement within the LiB cell. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

24 pages, 3291 KiB

Open AccessReview

Current Trends for State-of-Charge (SoC) Estimation in Lithium-Ion Battery Electric Vehicles

by Ingvild B. Espedal, Asanthi Jinasena, Odne S. Burheim and Jacob J. Lamb

Energies 2021, 14(11), 3284; https://doi.org/10.3390/en14113284 - 4 Jun 2021

Cited by 79 | Viewed by 9111

Abstract

Energy storage systems (ESSs) are critically important for the future of electric vehicles. Despite this, the safety and management of ESSs require improvement. Battery management systems (BMSs) are vital components in ESS systems for Lithium-ion batteries (LIBs). One parameter that is included in [...] Read more.

Energy storage systems (ESSs) are critically important for the future of electric vehicles. Despite this, the safety and management of ESSs require improvement. Battery management systems (BMSs) are vital components in ESS systems for Lithium-ion batteries (LIBs). One parameter that is included in the BMS is the state-of-charge (SoC) of the battery. SoC has become an active research area in recent years for battery electric vehicle (BEV) LIBs, yet there are some challenges: the LIB configuration is nonlinear, making it hard to model correctly; it is difficult to assess internal environments of a LIB (and this can be different in laboratory conditions compared to real-world conditions); and these discrepancies can lead to raising the instability of the LIB. Therefore, further advancement is required in order to have higher accuracy in SoC estimation in BEV LIBs. SoC estimation is a key BMS feature, and precise modeling and state estimation will improve stable operation. This review discusses current methods use in BEV LIB SoC modelling and estimation. The review culminates in a brief discussion of challenges in BEV LIB SoC prediction analysis. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

41 pages, 6989 KiB

Open AccessReview

Opportunities for the State-of-the-Art Production of LIB Electrodes—A Review

by Silje Nornes Bryntesen, Anders Hammer Strømman, Ignat Tolstorebrov, Paul R. Shearing, Jacob J. Lamb and Odne Stokke Burheim

Energies 2021, 14(5), 1406; https://doi.org/10.3390/en14051406 - 4 Mar 2021

Cited by 58 | Viewed by 8612

Abstract

A sustainable shift from internal combustion engine (ICE) vehicles to electric vehicles (EVs) is essential to achieve a considerable reduction in emissions. The production of Li-ion batteries (LIBs) used in EVs is an energy-intensive and costly process. It can also lead to significant [...] Read more.

A sustainable shift from internal combustion engine (ICE) vehicles to electric vehicles (EVs) is essential to achieve a considerable reduction in emissions. The production of Li-ion batteries (LIBs) used in EVs is an energy-intensive and costly process. It can also lead to significant embedded emissions depending on the source of energy used. In fact, about 39% of the energy consumption in LIB production is associated with drying processes, where the electrode drying step accounts for about a half. Despite the enormous energy consumption and costs originating from drying processes, they are seldomly researched in the battery industry. Establishing knowledge within the LIB industry regarding state-of-the-art drying techniques and solvent evaporation mechanisms is vital for optimising process conditions, detecting alternative solvent systems, and discovering novel techniques. This review aims to give a summary of the state-of-the-art LIB processing techniques. An in-depth understanding of the influential factors for each manufacturing step of LIBs is then established, emphasising the electrode structure and electrochemical performance. Special attention is dedicated to the convection drying step in conventional water and N-Methyl-2-pyrrolidone (NMP)-based electrode manufacturing. Solvent omission in dry electrode processing substantially lowers the energy demand and allows for a thick, mechanically stable electrode coating. Small changes in the electrode manufacturing route may have an immense impact on the final battery performance. Electrodes used for research and development often have a different production route and techniques compared to those processed in industry. The scalability issues related to the comparison across scales are discussed and further emphasised when the industry moves towards the next-generation techniques. Finally, the critical aspects of the innovations and industrial modifications that aim to overcome the main challenges are presented. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

30 pages, 1333 KiB

Open AccessReview

Temperature, Ageing and Thermal Management of Lithium-Ion Batteries

by Lena Spitthoff, Paul R. Shearing and Odne Stokke Burheim

Energies 2021, 14(5), 1248; https://doi.org/10.3390/en14051248 - 25 Feb 2021

Cited by 56 | Viewed by 9918

Abstract

Heat generation and therefore thermal transport plays a critical role in ensuring performance, ageing and safety for lithium-ion batteries (LIB). Increased battery temperature is the most important ageing accelerator. Understanding and managing temperature and ageing for batteries in operation is thus a multiscale [...] Read more.

Heat generation and therefore thermal transport plays a critical role in ensuring performance, ageing and safety for lithium-ion batteries (LIB). Increased battery temperature is the most important ageing accelerator. Understanding and managing temperature and ageing for batteries in operation is thus a multiscale challenge, ranging from the micro/nanoscale within the single material layers to large, integrated LIB packs. This paper includes an extended literature survey of experimental studies on commercial cells investigating the capacity and performance degradation of LIB. It compares the degradation behavior in terms of the influence of operating conditions for different chemistries and cell sizes. A simple thermal model for linking some of these parameters together is presented as well. While the temperature appears to have a large impact on ageing acceleration above room temperature during cycling for all studied cells, the effect of SOC and C rate appear to be rather cell dependent.Through the application of new simulations, it is shown that during cell testing, the actual cell temperature can deviate severely from the reported temperature depending on the thermal management during testing and C rate. It is shown, that the battery lifetime reduction at high C rates can be for large parts due to an increase in temperature especially for high energy cells and poor cooling during cycling studies. Measuring and reporting the actual battery (surface) temperature allow for a proper interpretation of results and transferring results from laboratory experiments to real applications. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures

Figure 1

28 pages, 737 KiB

Open AccessReview

Lithium-Ion Capacitors: A Review of Design and Active Materials

by Jacob J. Lamb and Odne S. Burheim

Energies 2021, 14(4), 979; https://doi.org/10.3390/en14040979 - 12 Feb 2021

Cited by 40 | Viewed by 5588

Abstract

Lithium-ion capacitors (LICs) have gained significant attention in recent years for their increased energy density without altering their power density. LICs achieve higher capacitance than traditional supercapacitors due to their hybrid battery electrode and subsequent higher voltage. This is due to the asymmetric [...] Read more.

Lithium-ion capacitors (LICs) have gained significant attention in recent years for their increased energy density without altering their power density. LICs achieve higher capacitance than traditional supercapacitors due to their hybrid battery electrode and subsequent higher voltage. This is due to the asymmetric action of LICs, which serves as an enhancer of traditional supercapacitors. This culminates in the potential for pollution-free, long-lasting, and efficient energy-storing that is required to realise a renewable energy future. This review article offers an analysis of recent progress in the production of LIC electrode active materials, requirements and performance. In-situ hybridisation and ex-situ recombination of composite materials comprising a wide variety of active constituents is also addressed. The possible challenges and opportunities for future research based on LICs in energy applications are also discussed. Full article

(This article belongs to the Special Issue Advanced Technology to Improve Energy Efficiency and Storage)

► Show Figures