scholarly journals Influence of Efficiency, Aging and Charging Strategy on the Economic Viability and Dimensioning of Photovoltaic Home Storage Systems

Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7673
Author(s):  
Nina Munzke ◽  
Felix Büchle ◽  
Anna Smith ◽  
Marc Hiller
Keyword(s):  
Large Scale ◽  
Storage Systems ◽  
Storage System ◽  
Energy Transition ◽  
Pv System ◽  
Technical Parameters ◽  
Economic Framework ◽  
Ion Storage ◽  
Framework Conditions ◽  
Charging Strategy

PV in combination with Li-ion storage systems can make a major contribution to the energy transition. However, large-scale application will only take place when the systems are economically viable. The profitability of such a system is not only influenced by the investment costs and economic framework conditions, but also by the technical parameters of the storage systems. The paper presents a methodology for the simulation and sizing of PV home storage systems that takes into account the efficiency of the storage systems (AC, DC standby consumption and peripheral consumption, battery efficiency and inverter efficiency), the aging of the components (cyclic and calendar battery aging and PV degradation), and the intelligence of the charging strategy. The developed methodology can be applied to all regions. In this paper, a sensitivity analysis of the influence of the mentioned technical parameters on the dimensioning and profitability of a PV home storage is performed. The calculation is done for Germany. Especially, battery aging, battery inverter efficiency and a charging strategy to avoid calendar aging have a decisive influence. While optimization of most other technical parameters only leads to a cost reduction of 1–3%, more efficient inverters can save up to 5%. Even higher cost reductions (more than 20%) can only be achieved using batteries that age less, especially batteries that are less sensitive to calendar aging. In individual cases, a small improvement in the efficiency of the storage system can also lead to higher costs. This is for example the case when smaller batteries are combined with a large PV system and the battery is used more due to the higher efficiency. This results in faster ageing and thus earlier replacement of the battery. In addition, the paper includes a detailed literature overview on PV home storage system sizing and simulation.

scholarly journals Design of a Smart Nanogrid for Increasing Energy Efficiency of Buildings

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3683
Author(s):  
Yerasimos Yerasimou ◽  
Marios Kynigos ◽  
Venizelos Efthymiou ◽  
George E. Georghiou
Keyword(s):  
Storage System ◽  
Energy Transition ◽  
Energy Storage System ◽  
Low Carbon ◽  
Pv System ◽  
Interconnected System ◽  
Low Carbon Economy ◽  
Energy Needs ◽  
Energy Domain ◽  
Battery Energy

Distributed generation (DG) systems are growing in number, diversifying in driving technologies and providing substantial energy quantities in covering the energy needs of the interconnected system in an optimal way. This evolution of technologies is a response to the needs of the energy transition to a low carbon economy. A nanogrid is dependent on local resources through appropriate DG, confined within the boundaries of an energy domain not exceeding 100 kW of power. It can be a single building that is equipped with a local electricity generation to fulfil the building’s load consumption requirements, it is electrically interconnected with the external power system and it can optionally be equipped with a storage system. It is, however, mandatory that a nanogrid is equipped with a controller for optimisation of the production/consumption curves. This study presents design consideretions for nanogrids and the design of a nanogrid system consisting of a 40 kWp photovoltaic (PV) system and a 50 kWh battery energy storage system (BESS) managed via a central converter able to perform demand-side management (DSM). The implementation of the nanogrid aims at reducing the CO2 footprint of the confined domain and increase its self-sufficiency.

Rational design of a tubular, interlayer expanded MoS2–N/O doped carbon composite for excellent potassium-ion storage

2019 ◽  
Vol 7 (15) ◽  
pp. 9305-9315 ◽  
Author(s):  
Nan Zheng ◽  
Guangyu Jiang ◽  
Xiao Chen ◽  
Jiayi Mao ◽  
Yajun Zhou ◽  
...  
Keyword(s):  
Energy Storage ◽  
Rational Design ◽  
Large Scale ◽  
Storage System ◽  
Energy Storage System ◽  
Carbon Composite ◽  
Potassium Ion ◽  
Electrochemical Energy Storage ◽  
Ion Storage ◽  
Electrochemical Energy

Potassium ion batteries (KIBs) are the emerging and promising energy storage system for large-scale electrochemical energy storage.

Performance of Thermal Enhancement Materials in High Pressure Metal Hydride Storage Systems

2008 ◽  
Author(s):  
Timothe´e L. Pourpoint ◽  
Aaron Sisto ◽  
Kyle C. Smith ◽  
Tyler G. Voskuilen ◽  
Milan K. Visaria ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
High Pressure ◽  
Metal Hydride ◽  
Large Scale ◽  
Storage Systems ◽  
Storage System ◽  
Hydrogen Gas ◽  
Thermal Enhancement ◽  
Hydrogen Systems ◽  
Hydride Powder

Over the past two years, key issues associated with the development of realistic metal hydride storage systems have been identified and studied at Purdue University’s Hydrogen Systems Laboratory, part of the Energy Center at Discovery Park. Ongoing research projects are aimed at the demonstration of a prototype large-scale metal hydride tank that achieves fill and release rates compatible with current automotive use. The large-scale storage system is a prototype with multiple pressure vessels compatible with 350 bar operation. Tests are conducted at the Hydrogen Systems Lab in a 1000 ft2 laboratory space comprised of two test cells and a control room that has been upgraded for hydrogen service compatibility. The infrastructure and associated data acquisition and control systems allow for remote testing with several kilograms of high-pressure reversible metal hydride powder. Managing the large amount of heat generated during hydrogen loading directly affects the refueling time. However, the thermal management of hydride systems is problematic because of the low thermal conductivity of the metal hydrides (∼ 1 W/m-K). Current efforts are aimed at optimizing the filling-dependent thermal performance of the metal hydride storage system to minimize the refueling time of a practical system. Combined heat conduction within the metal hydride and the enhancing material particles, across the contacts of particles and within the hydrogen gas between non-contacted particles plays a critical role in dissipating heat to sustain high reaction rates during refueling. Methods to increase the effective thermal conductivity of metal hydride powders include using additives with substantially higher thermal conductivity such as aluminum, graphite, metal foams and carbon nanotubes. This paper presents the results of experimental studies in which various thermal enhancement materials are added to the metal hydride powder in an effort to maximize the effective thermal conductivity of the test bed. The size, aspect ratio, and intrinsic thermal conductivity of the enhancement materials are taken into account to adapt heat conduction models through composite nanoporous media. Thermal conductivity and density of the composite materials are measured and enhancement metrics are calculated to rate performance of composites. Experimental results of the hydriding process of thermally enhanced metal hydride powder are compared to un-enhanced metal hydride powder and to model predictions. The development of the Hydrogen Systems Laboratory is also discussed in light of the lessons learned in managing large quantities of metal hydride and high pressure hydrogen gas.

scholarly journals Scenario-based mission statements

2021 ◽  
Vol 30 (1) ◽  
pp. 29-35
Author(s):  
Raphael Dietz ◽  
Dan Teodorovici ◽  
Sigrid Busch ◽  
Markus Blesl ◽  
Michael Ruddat ◽  
...  
Keyword(s):  
Large Scale ◽  
Planning Process ◽  
Mission Statement ◽  
Energy Transition ◽  
Mission Statements ◽  
Inertial Forces ◽  
Transdisciplinary Approach ◽  
Energy Infrastructure ◽  
Framework Conditions

Using a planning process for the Stuttgart Neckar Valley as a case study, this paper analyzes the urban inertial forces that counteract the transformation of energy infrastructure areas in the context of the energy transition. In order to overcome these forces, a scenario-based mission statement was developed in which spatial scenarios were derived from energy scenarios and finally summarized in a concept plan for the Neckar Valley. The mission statement was developed following an analytical-deliberative and transdisciplinary approach. The approach to mission statement development presented here can respond flexibly to changing framework conditions and thus serve as a model for other cities with large-scale energy infrastructures in transition.

scholarly journals MonkeyDB: effectively testing correctness under weak isolation levels

2021 ◽  
Vol 5 (OOPSLA) ◽  
pp. 1-27
Author(s):  
Ranadeep Biswas ◽  
Diptanshu Kakwani ◽  
Jyothi Vedurada ◽  
Constantin Enea ◽  
Akash Lal
Keyword(s):  
Social Networking ◽  
Large Scale ◽  
Storage Systems ◽  
Storage System ◽  
Trade Off ◽  
Read Operation ◽  
A Value ◽  
Logical Specification ◽  
Good Coverage

Modern applications, such as social networking systems and e-commerce platforms are centered around using large-scale storage systems for storing and retrieving data. In the presence of concurrent accesses, these storage systems trade off isolation for performance. The weaker the isolation level, the more behaviors a storage system is allowed to exhibit and it is up to the developer to ensure that their application can tolerate those behaviors. However, these weak behaviors only occur rarely in practice and outside the control of the application, making it difficult for developers to test the robustness of their code against weak isolation levels. This paper presents MonkeyDB, a mock storage system for testing storage-backed applications. MonkeyDB supports a key-value interface as well as SQL queries under multiple isolation levels. It uses a logical specification of the isolation level to compute, on a read operation, the set of all possible return values. MonkeyDB then returns a value randomly from this set. We show that MonkeyDB provides good coverage of weak behaviors, which is complete in the limit. We test a variety of applications for assertions that fail only under weak isolation. MonkeyDB is able to break each of those assertions in a small number of attempts.

scholarly journals Optimal Integration of Hydrogen-Based Energy Storage Systems in Photovoltaic Microgrids: A Techno-Economic Assessment

Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4149
Author(s):  
Fabio Serra ◽  
Marialaura Lucariello ◽  
Mario Petrollese ◽  
Giorgio Cau
Keyword(s):  
Cost Effectiveness ◽  
Energy Production ◽  
Storage Systems ◽  
Storage System ◽  
Economic Assessment ◽  
Pv System ◽  
Hydrogen Storage System ◽  
Cost Of Energy ◽  
Expected Performance ◽  
The Cost

The feasibility and cost-effectiveness of hydrogen-based microgrids in facilities, such as public buildings and small- and medium-sized enterprises, provided by photovoltaic (PV) plants and characterized by low electric demand during weekends, were investigated in this paper. Starting from the experience of the microgrid being built at the Renewable Energy Facility of Sardegna Ricerche (Italy), which, among various energy production and storage systems, includes a hydrogen storage system, a modeling of the hydrogen-based microgrid was developed. The model was used to analyze the expected performance of the microgrid considering different load profiles and equipment sizes. Finally, the microgrid cost-effectiveness was evaluated using a preliminary economic analysis. The results demonstrate that an effective design can be achieved with a PV system sized for an annual energy production 20% higher than the annual energy requested by the user and a hydrogen generator size 60% of the PV nominal power size. This configuration leads to a self-sufficiency rate of about 80% and, without public grants, a levelized cost of energy comparable with the cost of electricity in Italy can be achieved with a reduction of at least 25–40% of the current initial costs charged for the whole plant, depending on the load profile shape.

scholarly journals Hydrogen as a Long-Term Large-Scale Energy Storage Solution to Support Renewables

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2825 ◽  
Author(s):  
Subodh Kharel ◽  
Bahman Shabani
Keyword(s):  
Energy Storage ◽  
Hydrogen Storage ◽  
Large Scale ◽  
Storage Systems ◽  
Storage System ◽  
Unit Cost ◽  
South Australia ◽  
Point Of View ◽  
Cost Of Electricity

This paper presents a case study of using hydrogen for large-scale long-term storage application to support the current electricity generation mix of South Australia state in Australia, which primarily includes gas, wind and solar. For this purpose two cases of battery energy storage and hybrid battery-hydrogen storage systems to support solar and wind energy inputs were compared from a techno-economical point of view. Hybrid battery-hydrogen storage system was found to be more cost competitive with unit cost of electricity at $0.626/kWh (US dollar) compared to battery-only energy storage systems with a $2.68/kWh unit cost of electricity. This research also found that the excess stored hydrogen can be further utilised to generate extra electricity. Further utilisation of generated electricity can be incorporated to meet the load demand by either decreasing the base load supply from gas in the present scenario or exporting it to neighbouring states to enhance economic viability of the system. The use of excess stored hydrogen to generate extra electricity further reduced the cost to $0.494/kWh.

scholarly journals Dynamic Modelling and Techno-Economic Assessment of a Compressed Heat Energy Storage System: Application in a 26-MW Wind Farm in Spain

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4739 ◽  
Author(s):  
Violeta Sánchez-Canales ◽  
Jorge Payá ◽  
José M. Corberán ◽  
Abdelrahman H. Hassan
Keyword(s):  
Energy Storage ◽  
Power Plant ◽  
Electricity Market ◽  
Large Scale ◽  
Storage Systems ◽  
Capital Expenditure ◽  
Renewable Energy Sources ◽  
Storage System ◽  
Dynamic Modelling ◽  
Heat Energy

One of the main challenges for a further integration of renewable energy sources in the electricity grid is the development of large-scale energy storage systems to overcome their intermittency. This paper presents the concept named CHEST (Compressed Heat Energy STorage), in which the excess electricity is employed to increase the temperature of a heat source by means of a high-temperature heat pump. This heat is stored in a combination of latent and sensible heat storage systems. Later, the stored heat is used to drive an organic Rankine cycle, and hereby to produce electricity when needed. A novel application of this storage system is presented by exploring its potential integration in the Spanish technical constraints electricity market. A detailed dynamic model of the proposed CHEST system was developed and applied to a case study of a 26-MW wind power plant in Spain. Different capacities of the storage system were assessed for the case under study. The results show that roundtrip efficiencies above 90% can be achieved in all the simulated scenarios and that the CHEST system can provide from 1% to 20% of the total energy contribution of the power plant, depending on its size. The CHEST concept could be economically feasible if its capital expenditure (CAPEX) ranges between 200 and 650 k€/MW.

Rethinking key–value store for parallel I/O optimization

2016 ◽  
Vol 31 (4) ◽  
pp. 335-356 ◽  
Author(s):  
Anthony Kougkas ◽  
Hassan Eslami ◽  
Xian-He Sun ◽  
Rajeev Thakur ◽  
William Gropp
Keyword(s):  
Cloud Storage ◽  
Large Scale ◽  
Storage Systems ◽  
Storage System ◽  
File Systems ◽  
Data Synchronization ◽  
Input Output ◽  
Parallel File Systems ◽  
Parallel File ◽  
And Performance

Key–value stores are being widely used as the storage system for large-scale internet services and cloud storage systems. However, they are rarely used in HPC systems, where parallel file systems are the dominant storage solution. In this study, we examine the architecture differences and performance characteristics of parallel file systems and key–value stores. We propose using key–value stores to optimize overall Input/Output (I/O) performance, especially for workloads that parallel file systems cannot handle well, such as the cases with intense data synchronization or heavy metadata operations. We conducted experiments with several synthetic benchmarks, an I/O benchmark, and a real application. We modeled the performance of these two systems using collected data from our experiments, and we provide a predictive method to identify which system offers better I/O performance given a specific workload. The results show that we can optimize the I/O performance in HPC systems by utilizing key–value stores.

Sign in / Sign up

Export Citation Format

Share Document