Challenges and Opportunities of Distributed Renewable Power

Energy transition is a current global challenge. Deciding a right path to meet the ever-increasing global energy demand at an affordable cost with low-carbon options is a critical challenge. Deciding appropriate energy strategies and determining their priorities are necessary for proper energy transition. Energy strategy determination is decided on the basis of the country's strengths, weaknesses, opportunities, and threats (SWOT) related to the energy sector. Evaluating proper energy strategies is a perpetual process to prioritize issues in energy planning. Different authorities are responsible for deciding the proper priorities of energy strategies on the basis of new and improved alternative solutions to achieve sustainable development. As energy strategy prioritization correlates several conflicting and interlinked issues and the SWOT method is unable to decide the priority, integrating a multi-criteria decision-making (MCDM) approach is critical. Integrating SWOT with an MCDM method is generic yet novel and one of the best possible options to formulate and prioritize energy strategies for a better energy transition towards sustainability. The study comprehensively reviewed the SWOT-MCDM methods along with the future direction of the research applied in different fields specially focused on energy transition.

With rapid urbanization, the need for energy usage has become more dominant than any other demand in modern society. With rapidly depleting fossil fuel sources, seconded by the need for environmental protection, the search for new and renewable energy (RE) sources has gained immense importance as sustainable alternatives. However, because of the intermittent and unpredictable nature of many of these RE sources, it has become imperative that their greatest benefit can only be harnessed when they are integrated into existing electric power networks. In this context, the greatest impetus toward comprehending a sustainable future is evolution of technology for integration of RE sources in electric power network and its control. There are various issues to be addressed while integrating RE sources to the power grid, including technical, economic, societal, and other challenges. This chapter begins by introducing the opportunities of integrating RES into the power grid, followed by their scopes and benefits. The various challenges faced while integrating RE into the power grid are further explained with specific case studies. Possible solutions to these issues are discussed in the next sections. Progress in the area of development of mathematical models of RE systems for studies related to grid integration is highlighted. Simulation tools that are being used by the research community for RE integration and control applications are introduced. Finally, some recent research works on RE integration-related activities are presented. This book chapter thus aims to enrich the knowledge base in green energy systems and opens up new horizons for simulation and experimental studies to address the crucial need of power industry in exploring power electronics, control technology, information and communication technology (ICT), and smart grid technology for supporting RE integration to grid.

The rising demand for petroleum-based fuels, coupled with escalating environmental concerns, has encouraged the scientific community to focus on exploring alternative energy resources for power generation. Biomass, being renewable, carbon–neutral, and abundant, has significant potential for generating power with minimal environmental impact. Biomass energy has an estimated annual production capacity of 181.5 billion metric tonnes of which only 8.2 billion metric tonnes are presently utilized. There is significant potential in terms of technological advancement for the conversion of biomass energy. Among the various biomass conversion routes, the thermochemical conversion process has gained prominence since the late nineteenth century. This well-established technology encompasses various categories such as pyrolysis, torrefaction, carbonization, liquefaction, gasification, and combustion, depending on the feedstock and desired end product. The present chapter provides a comprehensive overview of the various thermochemical conversion processes, their working principles, and operating criteria. Furthermore, this chapter briefly explores various power generation pathways such as steam power plants, gasifier-IC engine combined technology, gasifier gas turbine combined technology, and gasification fuel cell combined technology available for thermo-chemically converted biomass. The various limitations and challenges associated with the thermochemical conversion process have been reported in this chapter. Currently, the global power generated from biomass sources is about 764.2 TWh as of 2021 having an average annual growth rate of about 7%. The government initiatives aimed at promoting biomass-based power generation are also discussed in detail. Moreover, techno-economic assessments, recent advancements in this field on the commercial scale, and their potential impact on CO₂ reduction are examined.

Biogas, generated through anaerobic digestion (AD) of organic feed-stocks like bio-wastes, is a sustainable and clean source of energy, capable of generating electricity, and direct thermal use. However, biogas is a mixture of methane and CO₂ and the latter does not contribute towards the overall heating value of the gaseous fuel. The AD process also generates digestate slurry which is generally rich in ammonia-based nitrogen, phosphorous, and potassium (NPK). While the solid part of the effluent is traditionally utilized as fertilizers, the liquid digestate requires proper treatment and management to prevent leach out and contamination of the ground water systems. Algal cultivation (AC), on the other hand, is gaining attention for CO₂ capture and for the generation of algal lipids and biochemicals, like proteins, carbohydrates, and pigments. Algal cultivation systems can be integrated as photo bioreactors for CO₂ scrubbing in a two stage system or as anaerobic membrane reactors combining AD and algal processes along with membrane filtration technology for enhancing nutrient recovery, Therefore, algal cultivation can act as a potential CO₂ trap for upgradation of the quality of biogas by enhancing methane concentration while utilizing the nutrient (NPK) rich effluent from AD process. The algal biomass can be further processed for the production of value-added biochemicals and bioenergy applications, like biodiesel production. The present article focuses on the prospects and challenges of the integration of AD and AC processes which can have potential implications on bioenergy sector.

An urgent need to resolve the unwanted climatic change and transition to renewable energy resources has driven significant development and research in advancing renewable energy storage systems. Energy storing approaches aid in efficiently utilizing renewable resources, maintaining their consistency, and having a reliable energy supply. This book chapter contributes significantly to the topic of renewable energy storage. It provides a detailed overview of thermal energy storage (TES) systems based on phase-change materials (PCMs), emphasizing their critical role in storing and releasing latent heat. Moreover, different types of PCMs and their selection criteria for electricity generation are also described. Meanwhile, the role of polymer in thermal energy storage systems is systematically presented in this chapter. Usages of PCM trapped polymer composites and their different fabrication methods including micro/nanoencapsulation by physical/chemical methods, porous polymeric framework, and shape-stabilization strategy are also discussed in detail. In addition, this chapter covers the wide application of PCMs based systems in solar energy storage including solar thermophotovoltaics, waste heat recovery (stationary waste heat recovery and portable waste heat recovery), solar thermoelectric generators, concentrated solar power plants (CSP) and energy conservation in buildings.

Hybrid Photovoltaic-Thermal panels combine the two traditional solar energy production technologies (photovoltaic and solar thermal) in a single compact piece of micro-cogeneration equipment. This technology is in line with the growing trend of decentralization and energy self-reliance, by producing locally and simultaneously both electricity and thermal energy. Photovoltaic-thermal collectors are in particular advantageous in settings where roof space is restricted, such as urban locations, due to the fact that the rate of solar energy conversion per unit of area is increased. In addition, the extraction of thermal energy results in the cooling of the PV cells, which improves their efficiency. This study looks at the main challenges and opportunities of photovoltaic thermal collectors. In the introduction the functioning principles of this technology are presented, including motivation for development, types, and methods of integration in the energy mix. Next, a literature review of the current research developments is carried out, followed by a presentation of the global market situation. The result of this analyses indicate that the main challenges of this technology are the cost of production, which can be higher than traditional PV panels, lack of standardization and policies. Some recommendations are that the development of additional demonstrative projects, improving the user awareness and additional proof of concept would be required in order to launch this technology further on the mass market.

The global share of renewable energy uses is to be increased to reduce the carbon footprint. Geothermal-based renewable resources are preferred for satisfying localized energy needs due to their steady and uninterrupted supply. However, geothermal-based energy systems are cost-intensive unless the geothermal heat is readily available. Many of the oilfields produce hot geothermal water at the stage of high water cut. Removing a larger amount of water produced at the high water cut stage of an oilfield is a compulsion. Thus, the hot water produced from the oilfield at the high water cut stage can be used to satisfy the localized energy needs fully or partially. On the other hand, many of the researchers proposed to recover geothermal heat from depleted oilfields. Recovering geothermal heat from depleted oil reservoirs would be an attractive option as there would be no additional cost of drilling the geothermal well. In this chapter, various techniques to recover and utilize geothermal heat are presented, along with a few relevant case studies. From the summarized case studies, it appears that recovering geothermal heat from older oilfields may emerge as one of the future carbon–neutral distributed energy options for delivering electricity and other energy utilities. It is necessary to mention that additional study and appropriate policy formulation are required to address potential obstacles and challenges in the practical application of geothermal heat recovery from oilfields.

Renewable energy and smart technology are crucial to sustainable and eco-friendly structures, as the chapter explains. This comprehensive plan empowers building owners, architects, energy managers, and legislators to use distributed renewables and smart solutions for environmental, energy, and financial benefits. Distributed renewables, their benefits and drawbacks, and their relevance and principles are covered in this chapter. Next, it discusses distributed renewables’ crucial role in sustainable buildings, including environmental, economic, and green building regulations. As smart technologies drive contemporary sustainability, the chapter examines those in detail. Smart buildings need IoT, building automation, data analytics, and energy management systems, which readers will learn about. Solar photovoltaics, wind power, battery storage, and microgrid solutions are extensively covered in the distribution of renewables in sustainable buildings. The guidance also emphasizes energy efficiency in building design and retrofitting. Examining building energy management, lighting control, HVAC automation, and security systems highlights smart building automation. With real-world case studies, data and analytics optimize energy use and achieve sustainability targets. This chapter addresses funding distributed renewable projects and using government incentives and rebates. To aid decision-making, ROI and payback times are explained. Addressing grid integration, cybersecurity, and implementation challenges, solutions are suggested. Future sustainable building themes include renewable technology, blockchain's involvement in energy trading, smart cities, and sustainable building certification standards. This chapter helps develop sustainable buildings using distributed renewables and smart technology. Knowledge and a commitment to a sustainable and resilient future are shared.

The ever-increasing demand for energy in the background of environmental concern is paving the way for replacement of fossil fuels with renewable energy sources. While hydropower is one of the most significant contributors in this sector for a long time, recent growth in renewables is coming from solar energy and wind energy. Despite their strong position of sustainability, a major problem of these sectors is the intermittent nature of energy supply. Hence, to suppress such fluctuations, energy storage is essential. Pumped hydro storage (PHS) in this context is one of the most attractive choices due to high efficiency, reliability and low cost. This paper discusses the use of PHS for removing the intermittency in supplies from solar and wind energy. The current state-of-art indicates that PHS shall be increasingly used in coming decades for energy generation in renewable and hybrid renewable sectors.

India can harness 40 GW of ocean energy from its 7500 km long coast. There are several devices to harness such power. One commonly researched device is an oscillating water column (OWC). One end of the duct faces the water, while the other is open to the atmosphere. When the wave enters the duct, the air is pushed out; when the wave recedes, the air gets sucked in. It uses an air duct, which contains a single turbine or two turbines. The conventional turbines face difficulty in harnessing this pneumatic energy as air direction changes with wave action in OWC. A bidirectional turbine can work in this situation without additional units. However, because of their symmetrical aerofoil geometry construction, these turbines have poorer efficiency than conventional air turbines. A pair of conventional turbines can be used with OWC such that one works as a power producer and another as a flow blocker. This turbine action reverses for the opposite wave cycle. However, the flow blocker turbine cannot block the airflow completely, causing poor performance at the power producer turbine. Mechanical valves can be placed along with the turbine to improve flow blockage, but this may be unreliable considering the ocean’s dynamic nature. A fluidic diode (FD), similar to an electrical diode, offers variable resistance based on flow direction. This can be used with OWC to improve the performance of the air turbines. This article discusses various FDs used for engineering applications and a detailed numerical study on the FD used for wave energy applications.

Biofuels can successfully replace fossil fuels as they emit less amount of greenhouse gas during combustion. Syngas fermentation is one of the sustainable routes of producing bioethanol, methane, etc., particularly from ligno-cellulosic biomass (LCB) rich in lignin. In this process, syngas generated via gasification of LCB is converted to liquid fuels with the aid of suitable microorganism (Clostridium carboxidivorans, Clostridium ljungdahlii, etc.) via acetyl-CoA pathway (Wood-Ljungdahl pathway). Syngas can also be converted to methane through microbial route. The present article discusses about the microbial principles, reactions and different reactors used for both bioethanol and methane production from syngas. The chapter aims to revisit the mathematical modelling practices for different reactors used for syngas fermentation for bioethanol formation along with identification of loopholes and possible recommendations.

The Self-excited Induction Generator (SEIG) is widely employed as a significant power generation source in geographically isolated rural areas inside the nation. Nevertheless, the functionality of the machine is limited by the fluctuating loading circumstances at its output. The uninterrupted provision of power supply is crucial for the efficient functioning of the system, as it ensures the continuous delivery of electricity to meet the demands of the consumer load. The utilization of an Electronic Load Controller (ELC) is employed within a self-excited induction generator system with the objective of sustaining a consistent voltage and frequency at the bus bar. One of the benefits of this technology is its ability to store and utilize excess kinetic energy at the receiving end for various purposes in rural regions. The study utilized induction machines with a power rating of 2.2 kW and a current rating of 4.8A. These machines were designed to operate at a voltage of 415 V and a frequency of 50 Hz. The excitation capacitor of the machines was employed to supply power to a three-phase load. Excess power generated is stored in a dump load battery. The suggested system underwent testing in the MATLAB/SIMULINK environment and was afterwards verified using the OP4510 RCP/HIL FPGA-based real-time simulator.

This paper explores the integration of a micro-hydro-based self-excited induction generator (SEIG) with the power grid to harness the advantages of renewable energy sources in the power sector. By incorporating renewable energy into the grid, significant enhancements can be achieved in terms of sustainability, economic viability, resilient capacity, and mitigation of power quality issues in generation and distribution. The study focuses on integrating a specific system comprising a 2.2 kW, 415-V, 50-Hz squirrel cage induction motor (SCIM) driving a three-phase SEIG. The MATLAB machine model is calibrated using machine parameters obtained through rigorous testing, including no-load characteristics, block rotor tests, magnetic saturation, and excitation capacitor calculations. A hydroelectric prime mover powers the SEIG realized with a 3.3 kW AC motor. Grid integration is facilitated through rectification and inversion operations employing an uncontrolled rectifier with a DC-link capacitor and a 6-pulse IGBT-based inverter. Switching operations utilize a voltage source converter (VSC) control topology based on synchronous reference frame theory. Simulations are conducted in the MATLAB/Simulink environment (R2018a version, 40,832,900), and the validity of the results is verified through real-time simulation using OPEL RT(OP4510). This investigation contributes to the understanding and implementation of micro-hydro-based self-excited induction generators for effective grid integration in the power sector.

Three-phase self-excited induction generator (SEIG) plays a vital role in micro-hydro systems (MHSs) to generate off-grid single-phase power for hilly terrain-based remote areas. In general, various capacitor excitation topologies (CETs) are available for supplying the requisite reactive power to the three-phase IG while producing single-phase power from the system. Generation of single-phase power from a three-phase SEIG driven by the MHS indicates a worst case of imbalance in the system in terms of phase voltages and stator currents of the generator. This chapter aims to implement a new CET to generate single-phase power from an MHS-driven 2.2 kW three-phase SEIG, whose stator is connected in delta, and the excitation cum reactive power is supplied from a star connected capacitor bank. The proposed CET-IG system is simulated in MATLAB/Simulink and analyzed in steady state for supplying single-phase load under fixed SEIG speed with 55% loading. The result indicates that the recommended CET can effectually supply the single-phase load having voltage regulation of 1.26% and exhibiting a perfect balance in the phase voltages and stator currents of the three-phase SEIG. Hence, in order to generate clean-cum-sustainable power practically in a cheap way for the remote hilly areas from hydro resources at small scale level (i.e., MHS), the proposed CET-IG scheme seems to be an effective one. The recommended CET therefore can be seen to supply the single-phase load in an efficient way, keeping the phase voltages and stator currents of the SEIG balanced while supporting a loading of 55%.

Power system harmonics, poor power factor, and unbalanced load are different and prominent problems in modern power networks. Also, for the standalone mode, voltage regulation is the major problem to tackle. It is always challenging to perform all corrective operations at once, but since these problems are theoretically correlated, one new algorithm is possible. Many techniques are available to solve these issues, but the complexity and lack of a single technique to solve these problems simultaneously have motivated this present work. An attempt is made to mitigate harmonics, correct the Power Factor (PF), and improve voltage regulation under balanced and unbalanced load conditions with a single and simple control technique using Shunt Active Power Filter (SAPF) based on p-q theory. Details of Self-Excited Induction Generator (SEIG) are discussed in this chapter. 2.2 kW SEIG has been considered for Hydro- electric power plant. The mathematical formulation is done and tested in the MATLAB environment, and the results are convincing and satisfactory.

India is a significant consumer in the World Energy Market. Electricity in India is majorly produced by non-renewable sources causing huge environmental pollution which in turn affects climate changes. With the increase in energy demand, there is a genuine need to switch towards renewable sources to protect our planet. Rural areas being rich in agricultural products are the good source of biomass resources. Hence, biomass gasification is a promising technology that can play a significant role in addressing both energy needs and environmental concerns. The present study is aimed at the performance study and the techno-economic analysis of a pilot-scale 10 kW fixed-bed downdraft gasifier integrated with a gas engine for distributed power generation in rural areas utilizing agriculture waste such as rice husk, wood chips, and dry leaves along with that comparison with diesel fuel engine as an alternative due rising fuel prices. A maximum overall gasification efficiency of 22.99% has been achieved with the current operating conditions which is reasonable for biomass-to-power application. The levelized unit cost of electricity (LUCE) of the biomass gasification-based power generation unit is found as 15.21 INR which is lower than the LUCE of a similar capacity diesel generator-based power generation system.

Solar energy-based power generation systems play a pivotal role in bolstering the Indian economy and contributing to India's energy security and independence. With reduced dependence on fossil fuel imports, solar power plants mitigate the risks associated with price volatility and supply disruptions in the conventional energy sector. By displacing fossil fuel-based electricity generation, solar power plants play a crucial role in mitigating climate change. India has implemented various solar-based power plants as part of its renewable energy initiatives. These power plants utilize different technologies and configurations to harness solar energy for electricity generation. Thus, the chapter explores the multifaceted role of solar energy by incorporating different solar-based technologies in developing the Indian economy. The chapter also enlightens their impact on job creation for economic growth, energy access in rural development as well as industrial development and technology transfer. Furthermore, government initiatives, along with supportive policies which possess significant importance in promoting solar energy adoption, attracting investments and driving the growth of the solar industry in India were also thoroughly covered because of their potential to bring transition in the sustainable development of the country.