Penetration Of Renewable Energy Technologies Research Articles

Comparing methods for criticality and security in minerals for clean energy

Global policy discussions have shifted towards clean energy economies, placing more emphasis on critical minerals and their supply chain security. Critical minerals typically have few substitutes, are essential to a modern technology, and susceptible to short- and long-term supply chain risks. Clean energy technologies require critical minerals for manufacturing, which presents a need for more dynamic considerations to identify risks in shorter timeframes. This paper reviews two methodologies employed for critical mineral identification from nations committed to clean energy transitions. Since the United States and the United Kingdom have committed to increasing their penetration of renewable energy technologies, critical minerals are of high importance, therefore the US National Science and Technology Council (2016), and the British Geological Survey (2015) methodologies are applied to critical minerals prioritized by the US and the UK. Comparing the results of the methodologies identified challenges with timescale applications, which could be problematic when identifying a flexible methodology that meets the needs of rapidly evolving clean energy economies. Other key findings include: applying a weighting across methodologies would allow for more robust comparisons between countries, rather than focusing on supply and market availability; and a broader methodology review could lead to greater transparency, data accessibility, and compatibility of clean energy strategies between nations and regions for energy security. Additionally, existing gaps in the literature are identified, along with suggestions for further work.

Hybrid solar energy systems with hydrogen and electrical energy storage for a single house and a midrise apartment in North America

Allowing deeper penetration of renewable energy technologies through the adaptation of hybrid systems is unanimously considered critical for decarbonizing the building sector. The objective of this research is to analyze and contrast different renewable energy systems utilizing PV panels, an electrolyzer, and a fuel cell (FC) in a single-house and a midrise apartment located in North America. The study uses HOMER software to simulate and optimize three types of systems: PV/battery bank, PV/hydrogen, and PV/battery bank/hydrogen. The findings indicate that larger batteries can be utilized in place of the electrolyzer and fuel cell, but they incur a higher net present cost (NPC) due to their expensive initial investment. Therefore, a combination of PV arrays, hydrogen, and smaller battery banks can significantly reduce the net present cost of the system while also achieving efficient performance. After conducting an economic analysis of various setups for a single house, the research indicates that a configuration of 522 kW photovoltaic (PV) panels, 150 kW electrolyzer, 20 kW fuel cell, 200 kg hydrogen tank, 18.6 kW converter, and 159 batteries offers the most favorable results in Toronto, Canada. This configuration achieves lower NPC and levelized cost of energy (COE) than the PV/hydrogen system. In addition, according to the optimum design of the hydrogen system for the midrise apartment, the PV/battery bank/hydrogen configuration has a lower NPC and COE than the PV/hydrogen system, which shows that adding the battery to the system lowers the cost and offer short and long-term energy storage. The optimum design was then verified by implementing a sensitivity analysis to evaluate different solar radiation, electric load, derating factor and tilt angle of the PV array.

Research on the Participation of Household Battery Energy Storage in the Electricity Peak Regulation Ancillary Service Market

Household battery energy storage (HBES) is expected to play an important role in the transition to decarbonized energy systems by enabling the further penetration of renewable energy technologies while assuring power grid stability. However, the hitherto high installation cost is a key barrier for further deployment of HBES. Therefore, in order to improve its economic feasibility, we will study how HBES participates in the electricity peak regulation ancillary service market (PRASM) in China, which can add new sources of income for HBES. When participating in PRASM, the market mechanism first needs to be understood, and the framework for participating in PRASM needs to be established. In this framework, HBES needs to be aggregated into a cluster by the aggregator to participate in PRASM. In this participation process, the aggregator first needs to determine the controllable capacity of HBES and analyze its uncertainty. After the upper limit of the controllable capacity is determined, the aggregator will be able to more accurately formulate the bidding strategy considering the reserve capacity and charging power allocation strategy to maximize the net income. In this paper, particle swarm optimization and chaos optimization are combined to solve this problem, and finally different scenarios are analyzed through example analysis. The results of the case analysis show that the bidding strategy considering the reserve capacity proposed in this paper can effectively reduce the output deviation value and has a relatively higher economy.

Experimental investigation and comparative analysis of immersion cooling of lithium-ion batteries using mineral and therminol oil

Renewable energy can potentially mitigate the adverse effects of energy and environmental crises. The Lithium-ion battery, a storage system investigated in the present study, has a potential to increase the penetration of renewable energy technologies, due to its high mass and volumetric energy density. However, thermal management strategies are necessary for lithium-ion battery electrical storage to grow technologically and gain widespread acceptability. In the present work, a comparative study of the different cooling methods, namely, forced air cooling (FAC), direct liquid contact cooling (i.e., Mineral oil cooling (MOC), and therminol oil cooling (TOC)) with low-cost coolants have been carried out on 20 cells of 10Ah lithium-ion battery-stack at a discharge rate of 1C, 1.5C, 2C, 2.5C, and 3C. It is found that the maximum temperature of the battery module is reduced by 43.83%, 49.17%, and 51.54% for forced air cooling, therminol oil cooling, and mineral oil cooling respectively, at 3C discharge rate, compared to the natural air-cooling method.Under the experimental conditions studied, the maximum temperature of the battery pack is found to be within the desired value during forced convection cooling only up to 1.5C discharge rate, while the immersion cooling performed satisfactorily up to 2C discharge rate. This study demonstrates direct liquid contact cooling with low-cost dielectric fluids as a safe and efficient thermal management technology for high-energy density and high-current lithium-ion battery applications.

A novel power management algorithm for a residential grid-connected PV system with battery-supercapacitor storage for increased self-consumption and self-sufficiency

The increasing penetration of renewable energy technologies causes major problems in the power network, as their generation cannot be totally predicted. Along with fluctuations in the generation of renewables due to weather uncertainties, storage is very important for mitigating several problems that may arise, affecting the stability and reliability of the grid. In particular, in recent years there has been an emphasis on residential storage applications (behind-the-meter storage), with the aim of increasing the energy self-consumption and therefore reducing electricity bills. The proposed model consists of a 3 kWp rooftop solar photovoltaic (PV) system connected to the grid through converters and a battery-supercapacitor hybrid energy storage system. The model is developed and simulated in the MATLAB/Simulink software environment, based on mathematical analysis and average modeling. The supercapacitor handles rapid changes that occur within 0.2 s, and this can relieve the battery stress and extend the battery lifetime. The building’s electricity demand is satisfied through the PV, hybrid energy storage and/or grid. A new filtration-based power management algorithm (PMA) is proposed here, prioritizing the utilization of the PV and battery-supercapacitor instead of the grid, thus achieving a reduced power exchange between the building and the grid and increasing the PV self-consumption and self-sufficiency of the building. The dynamic performance of the proposed model is verified through several simulations over short time periods (10–30 s) for different scenarios that could occur. The obtained results show that the model works properly and responds extremely fast during the different mode transitions, exhibiting a very fast DC-bus voltage regulation with a very small ripple voltage of up to 5 V (a maximum of ± 0.625%). Additionally, both battery and supercapacitor remain between their minimum and maximum limits. Finally, an effective power sharing is achieved between the PV, the battery-supercapacitor storage, the building load and the grid.

An Overview on Functional Integration of Hybrid Renewable Energy Systems in Multi-Energy Buildings

Buildings are responsible for over 30% of global final energy consumption and nearly 40% of total CO2 emissions. Thus, rapid penetration of renewable energy technologies (RETs) in this sector is required. Integration of renewable energy sources (RESs) into residential buildings should not only guarantee an overall neutral energy balance over long term horizon (nZEB concept), but also provide a higher flexibility, a real-time monitoring and a real time interaction with end-users (smart-building concept). Thus, increasing interest is being given to the concepts of Hybrid Renewable Energy Systems (HRES) and Multi-Energy Buildings, in which several renewable and nonrenewable energy systems, the energy networks and the energy demand optimally interact with each other at various levels, exploring all possible interactions between systems and vectors (electricity, heat, cooling, fuels, transport) without them being treated separately. In this context, the present paper gives an overview of functional integration of HRES in Multi-Energy Buildings evidencing the numerous problems and potentialities related to the application of HRESs in the residential building sector. Building-integrated HRESs with at least two RESs (i.e., wind–solar, solar–geothermal and solar–biomass) are considered. The most applied HRES solutions in the residential sector are presented, and integration of HRES with thermal and electrical loads in residential buildings connected to external multiple energy grids is investigated. Attention is focused on the potentialities that functional integration can offer in terms of flexibility services to the energy grids. New holistic approaches to the management problems and more complex architectures for the optimal control are described.

Comparative effectiveness of environmental regulation instruments: Case of the Moroccan electricity mix

<abstract> <p>Fossil fuels dominate the electricity mix of Morocco, the country is placing renewable energy at the heart of its energy strategy, to improve the security of supply and ensure environmental sustainability. However, the penetration of renewable energy technologies (RET) in the Moroccan electricity mix remains low due to an excess of investment in conventional energy technologies. This study first explores the characteristics of the Moroccan electricity mix before studying the dynamic effects of environmental regulatory instruments, in particular the carbon tax and the emission standards. To do so, we analyzed scenarios using a bottom-up linear and dynamic optimization model « OSeMOSYS» . We will therefore assess the impact of the carbon tax and the emission standards on RET adoption in the Moroccan electricity mix, over a period from 2015 to 2040. Our results suggest that environmental regulation in the electricity sector will lead to a large diversification of the Moroccan electricity mix with a large penetration of RET thus reducing the overall production of conventional energy technologies. Therefore, it follows that the carbon tax encourages the adoption of RET in the Moroccan electricity mix with significant reductions on fuel costs and operating & maintenance (O & M) costs of conventional energy technologies compared to emission standards.</p> </abstract>

Recent advances in low-temperature electrochemical conversion of carbon dioxide

Abstract Since the onset of the industrial revolution, fossil fuels have been the primary source of energy generation, and the continued exploitation of fossil fuels has led to an increase in the amount of atmospheric carbon dioxide. A lot of research currently focuses much on decreasing dependence on fossil fuels by replacing them with green energy. However, this technique poses a number of challenges, such as the need for improved infrastructure and technology and the high market penetration of renewable energy technologies. Capturing and converting carbon dioxide using electrochemical approaches can help to stabilize atmospheric greenhouse gas levels and create a positive future for the transformation of carbon dioxide into a number of value-added products. The conversion of carbon dioxide via electrochemical approach is a major challenge, and consideration must be given to the development and production of low-cost, stable, and highly efficient electrocatalysts. Hence, this review presents an overview of the current developments in the electrochemical conversion of carbon dioxide. In addition, this study discusses the current progress of electrocatalysts, in particular, the homogeneous and heterogeneous catalyst, which has a high level of activity and selectivity of low overpotential preferred products. The overview of the mechanisms and kinetics of the carbon dioxide reduction using the computational method are also addressed.

Investigation of the Low Voltage Ride-Through of Inverter Using Virtual Inertia Methods in Microgrid

Inverter based Distributed Energy Resources lack the inertia and damping features of synchronous generators dominated traditional power system. The growing penetration of renewable energy technologies coupled with their inherent intermittency also constitute grid instability challenge due to insignificant inertia and damping. The virtual inertia machine methods for the control of inverter based Distributed Energy Resources present the required inertia support that mimics the dynamic performance of a typical synchronous generator. These control methods provide excellent improvement in the stability of the grid. Several studies and implementations have been carried out on providing virtual inertia support for inverters in steady-state and under balanced grid voltage, however there is a need to investigate the dynamic performances during voltage sags occasioned by faults and other grid transients. Due to the low overvoltage and overcurrent tolerance capabilities of inverters, this investigation is important to observe the inverter transient behavior while ensuring the protection of constituent power electronic switches. Consequently, this work carried out an investigation to assess the two methods of Virtual Inertia Machine in ensuring the inverter sustained grid connection in compliance with grid codes, fault current limitation and fault recovery.

The nature of combining energy storage applications for residential battery technology

Batteries are expected to play an important role in the transition to decarbonised energy systems by enabling the further penetration of renewable energy technologies while assuring grid stability. However, their hitherto high capital costs is a key barrier for their further deployment. In order to improve their economic viability, batteries could provide several applications offering revenues. The techno-economic evaluation of batteries simultaneously serving several applications has proven to be challenging due to the trade-offs between energy and power applications. Focusing on residential batteries, we develop an optimisation method for designing optimal value propositions and we test it for four different applications both individually and jointly: PV self-consumption, demand load-shifting, avoidance of PV curtailment and demand peak shaving. Our results show that the combination of all applications currently helps batteries to get closer to profitability, from a net present value (NPV) per unit of capital expenditure (CAPEX) of −0.63 ± 0.04 for PV self-consumption only to −0.36 ± 0.10, with the combination of demand peak-shaving and PV self-consumption adding most value (0.21 ± 0.04). We also find that the annual household’s electricity consumption determines the value of energy storage applications. The proposed method allow us to classify storage applications as complementary and substitutive depending on whether their combined application increases their economic attractiveness or not. These results thus offer valuable insight for stakeholders interested in the deployment of energy storage in combination with energy efficiency, heat pumps and electric vehicles such as consumers, utility companies and policy makers.

Policy pathways for renewable and sustainable energy utilisation in rural coastline communities in the Niger Delta zone of Nigeria

This paper presents the major barriers to sustainable rural electrification in the Niger Delta zone and suggests practicable policy pathways to tackle the barriers to the aggressive utilisation of renewable energy technologies in the Niger Delta zone. The barrier to the penetration of renewable energy technologies in the Niger Delta zone can be grouped into policy and institutional, technical, data and information gathering, socio-cultural and behavioural, economic and financial, political and market barrier, and inadequate decision space. The suggested policy pathways are driven from both the energy access and affordability considerations. Potential stakeholders, as the key drivers of the policy pathways, are identified with their various attributes and roles. It is shown that both positive energy policies of the Federal Government of Nigeria towards renewable energy penetration and the support from the oil producing and allied companies towards their operational areas would see the aggressive adoption and assimilation of the renewable energy technologies to meet the energy needs of the Niger Delta zone. This comprehensive paper will serve as a reference for policy players in the quest to address the energy problems in the coastal communities. It is anticipated that policy briefs, directed at the relevant stakeholders, would be crafted in deeper fashion to identify various actors and teasing what can be done in the sustainable energy space.

Small island developing states and their suitability for electric vehicles and vehicle-to-grid services

Small Island Developing States (SIDS), while at the forefront of international climate action, face a number of development challenges linked to their historic, geographic and socio-economic characteristics. Small populations and limited energy demand cap the penetration of renewable energy technologies. Electric vehicles (EVs) offer solutions for electricity storage, grid services, reduced fuel imports, and reduced pollution with associated health benefits. This paper provides a comprehensive review of literature on island applications of electric vehicles, making the case for SIDS as an area of opportunity for further exploration, and presenting the southern Caribbean island of Barbados as a case study.

Cost-effective architecture of carbon capture and storage (CCS) grid in India

Various modeling studies analyzing global 2°C climate stabilization scenarios have projected penetration of CO2 capture and storage (CCS) technologies in India alongside a sizable penetration of renewable energy technologies. The assessments of geological storage potential over India have shown wide variation across regions. This paper examines the locations of large point sources of CO2 emissions in India and matches it with carbon storage locations to minimize the cost of CCS evolving grid. The concept of weighted Euclidean distance and Integrated Environmental Control Model are used to propose suitable pipeline networks for emissions-intensive clusters to optimize the cost of CO2 avoidance. The computational method estimates proximate storage location for each CO2 emitting source taking into account the total storage potential at each location. CCS requirement in India would vary depending on the global climate stabilization target. We examine two targets for India that correspond to 2°C and well below 2°C global mitigation regimes. According to our estimates, India could mitigate around 780 Mt CO2 per year below 60$/t-CO2 (2005 prices) over 30 years, and another 250 Mt CO2 per year for up to 75$/t-CO2 prices through CCS under these scenarios respectively.

Techno-economic and environmental analysis of power generation expansion plan of Ghana

This paper examines the current electrical generation expansion plan of Ghana and compares it with proposed expansion pathways with higher penetration of Renewable Energy Technologies. An adaptation of Schwartz's Scenario Methodology was used to develop the scenarios which were then analysed using the Long-range Alternatives Planning (LEAP) model. Each of the scenarios represents policy options for generation expansion in Ghana up to 2040. Energy, economic and environmental analysis of the three alternative scenarios compared to the base scenarios was undertaken. Sensitivity results show that, if the country were to follow the generation expansion path described in the renewable energy scenarios, it could reap economic benefits of 0.5–13.23% depending on the developments in fuel prices and renewable technology capital cost. The analysis further quantifies benefits to be derived from a reduction in Greenhouse gases of the scenarios. Policy implications for the generation system of Ghana based on the results are also discussed.

Induced technological change and the timing of public R&D investment in the Japanese electricity sector considering a two-factor learning curve

The UNFCCC has stated that energy policies and measures to address climate change should be cost-effective to ensure global benefits at the lowest possible cost. To mitigate the bulk of carbon emission from the electricity sector, a large market penetration of renewable energy technologies with as low cost as possible is a key research topic. The energy-related R&D policy in Japan aims to achieve a green economy. In our study, based on this context, we demonstrated how to optimize the timing of public R&D investment within the framework of a bottom-up partial equilibrium model. The developed optimization model represents the Japanese electricity sector and minimizes the total system cost subject to an accumulated carbon emission constraint. Our main research focus is the role of R&D activity, especially in the innovation stage of renewable technologies. We employ a two-factor learning curve and quantify the impact of the learning effect on the dynamic diffusion of major renewable technologies. The study shows a dynamic technology transition in the Japanese electricity sector and the optimized R&D investment schedule for each renewable technology. With the first-best energy policy, an R&D budget of more than 2000 million USD would be allocated to PV in 2050, which corresponds to 45% of the energy-related Japanese R&D budget in 2050. Because some have criticized the uncertainty problems with dynamic simulations and learning models, supplemental sensitivity analyses are included.

Analyses of optimum generation scenarios for sustainable power generation in Ghana

This study examines optimum generation scenarios for Ghana from 2010 to 2040. The Open Source Energy Modelling System (OSeMOSYS), an optimisation model for long term energy planning, which is integrated in Long-range Energy Alternatives Planning (LEAP) tool, was applied to model the generation system. The developed model was applied to the case study of the reference scenario (OPT) which examines the least cost development of the system without any shift in policy. Three groups of policy scenario were developed based on the future possible energy policy direction in Ghana: energy emission targets, carbon taxes and transmission and distribution losses improvements. The model was then used to simulate the development of technologies in each scenario up to 2040 and the level of renewable generation examined. Finally, cost benefit analysis of the policy scenarios, as well as their greenhouse gas mitigation potential were also discussed. The results show that: suitable policies for clean power generation have an important role in CO2 mitigation in Ghana. The introduction of carbon minimisation policies will also promote diversification of the generation mix with higher penetration of renewable energy technologies, thus reducing the overall fossil fuel generation in Ghana. It further indicated that, significant greenhouse emissions savings is achieved with improvement in transmission and distribution losses.

Sizing and economic analysis of gravity storage

Energy storage plays a key role in providing more flexibility and balancing to the electric grid. With the increasing penetration of renewable energy technologies, there is a need to instantaneously match demand with supply. Energy storage has the potential to provide a back-up to intermittent renewable energy by storing electricity for use during more valuable periods. At this time, there are limited storage options, because several technologies are at very early stage of development. Pumped hydro energy storage is currently the most widely installed technology. This form of storage has some drawbacks which include the technology siting, as it cannot be implemented everywhere. This paper presents a concept that is similar to the existing pumped hydro storage technology. This concept is known as gravity storage, as it stores electricity in the form of gravitational potential energy. This storage option provides better operating characteristics and economically sounds solution over conventional pumped hydro storage, and can be placed almost anywhere electricity storage is needed. This paper proposes a methodology to optimally size the gravity storage technology and avoid system design failure. It also presents an economic analysis to investigate the value of this storage option. This work identifies the leveled cost of gravity storage and compares it to similar storage options.

The Economics of Renewable Energy Sources into Electricity Generation in Tanzania

The study analyzes the economics of renewable energy sources into electricity generation in Tanzania. Business as usual (BAU) scenario and renewable energy (RE) scenario which enforce a mandatory penetration of renewable energy sources shares into electricity generations were analyzed. The results show total investment cost for the BAU scenario is much lower as compared to RE scenario while operating and maintenance variable costs are higher in BAU scenario. Primary energy supply in BAU scenario is higher tied with less investment costs as compared to RE scenario. Furthermore, the share of renewable energy sources in BAU scenario is insignificant as compared to RE scenario due to mandatory penetration policy imposed. Analysis concludes that there are much higher investments costs in RE scenario accompanied with less operating and variable costs and lower primary energy supply. Sensitivity analysis carried out suggests that regardless of changes in investments cost of coal and CCGT power plants, the penetration of renewable energy technologies was still insignificant. Notwithstanding the weaknesses of renewable energy technologies in terms of the associated higher investments costs, an interesting result is that it is possible to meet future electricity demand based on domestic resources including renewables.

The design and economics of low carbon fuel standards

Low carbon fuel standards (LCFS) are increasingly common policy tools used to decrease emissions and increase the penetration of renewable energy technologies in the transportation sector. In this paper, we discuss important design elements of the policy, and provide a background on prominent policies that are currently enacted or proposed. The economics of an LCFS are presented using a simple conceptual model, and the economic literature on the policy is reviewed. Important opportunities to build on the extant literature are identified, including studying the role of low carbon fuel standards in spurring technical change, and the interaction of the policy with other federal and state transportation policies.

The Impact of Learning-by-doing and Learning-by-searching on the Diffusion of Renewable Energy Technologies in the Japanese Electricity Sector

The mitigation of climate change is thought by many to be a significant environmental concern. In order to mitigate the bulk of carbon emissions from the electricity sector, large market penetration of renewable energy technologies is a key research issue. The goal of the paper is to address the timing of public RD investment for renewable technologies in the Japanese electricity sector. The model is cast as a dynamic bottom-up energy-system model and numerically optimized, minimizing a total system cost subject to an accumulated carbon emission constraint. Autonomous energy-efficiency improvement and two-factor learning curves describe the technological development process for each energy technology. With the two-factor learning curve, the model shows that the cost of electricity of renewable technologies can be reduced by up to 43% in the year 2100 if there is no constraint on public RD budget. Renewable energy sources requires substantial RD support in their initial phase of development; however, the investment pattern would switch to a path of reducing the amount after 2050. The budget of RD investment is strictly limited; thus, an important policy objective is to design a dynamic investment schedule that will induce sustainable innovations for green technologies.