Energy systems across the globe are going through a radical transformation as a result of technological and institutional changes, depletion of fossil fuel resources, and climate change. At the local level, increasing distributed energy resources requires that the centralized energy systems be re-organized. In this paper, the concept of Integrated community energy systems (ICESs) is presented as a modern development to re-organize local energy systems to integrate distributed energy resources and engage local communities. Local energy systems such as ICESs not only ensure self-provision of energy but also provide essential system services to the larger energy system. In this regard, a comparison of different energy system integration option is provided. We review the current energy trends and the associated technological, socio-economic, environmental and institutional issues shaping the development of ICESs. These systems can be applied to both developed and developing countries, however, their objectives, business models as well as composition differs. ICESs can be accepted by different actors such as local governments, communities, energy suppliers and system operators as an effective means to achieve sustainability and thereby will have significant roles in future energy systems.

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Energetic communities for community energy: A review of key issues and trends shaping integrated community energy systems

Solar energy programs for rural electrification: Experiences and lessons from South Asia

In this paper, we detail the design, analysis, and implementation of a highly distributed off-grid solar photovoltaic dc microgrid architecture suitable for rural electrification in developing countries. The proposed architecture is superior in comparison with existing architectures for rural electrification because of its 1) generation and storage scalability, 2) higher distribution efficiency (because of distributed generation and distributed storage for lower line losses), 3) ability to provide power for larger communal loads without the requirement for large, dedicated generation by extracting the benefit of usage diversity, and 4) localized control by using the hysteresis-based voltage droop method, thus eliminating the need for a central controller. The proposed microgrid architecture consists of several nanogrids capable of the self-sustained generation, storage, and bidirectional flow of power within the microgrid. Bidirectional power flow and distributed voltage droop control are implemented through the duty cycle control of a modified flyback converter. A detailed analysis in terms of power flow, loss, and system efficiency was conducted by using the Newton–Raphson method modified for dc power flow at varying distribution voltages, conductor sizes, and schemes of interconnection among the contributing nanogrids. A scaled-down version of the proposed architecture with various power sharing scenarios was also implemented on hardware, and yielded satisfactory results.

Solar PV-Based Scalable DC Microgrid for Rural Electrification in Developing Regions

Mini-grid based off-grid electrification to enhance electricity access in developing countries: What policies may be required?

DC microgrids built through a bottom-up approach are becoming popular for swarm electrification due to their scalability and resource-sharing capabilities. However, they typically require sophisticated control techniques involving communication among the distributed resources for stable and coordinated operation. In this work, we present a communication-less strategy for the decentralized control of a photovoltaic (PV)/battery-based highly distributed dc microgrid. The architecture consists of clusters of nanogrids (households), where each nanogrid can work independently along with provisions of sharing resources with the community. An adaptive I–V droop method is used, which relies on local measurements of state of charge and dc bus voltage for the coordinated power sharing among the contributing nanogrids. PV generation capability of individual nanogrids is synchronized with the grid stability conditions through a local controller, which may shift its modes of operation between maximum power point tracking mode and current control mode. The distributed architecture with the proposed decentralized control scheme enables 1) scalability and modularity in the structure, 2) higher distribution efficiency, and 3) communication-less, yet coordinated resource sharing. The efficacy of the proposed control scheme is validated for various possible power-sharing scenarios using simulations on MATLAB/Simulink and hardware-in-the-loop facilities at the Microgrid Laboratory, Aalborg University.

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A Decentralized Control Architecture Applied to DC Nanogrid Clusters for Rural Electrification in Developing Regions

New partnerships and business models for facilitating energy access

Bringing modern electricity services to more than 450 million South Asians without access to grid electricity calls for a variety of innovative mechanisms. Since off-grid electricity implementation is ipso facto decentralized, many have been able to experiment with different business models for implementation. This chapter examines various business models in rural electrification with a focus on off-grid models using clean sources of energy. The chapter also aims to understand how different organizations have modeled their off-grid and rural electrification programmes and what have been successful and challenging about each model. Given the vastness of the literature available on various electrification models adopted across the world, the review will necessarily be a partial one, however an attempt has been made to capture the models prevalent in the South Asian region and their essential features.

Participatory Business Models for Off-Grid Electrification

Conventional grid extension has been the predominant mode of electrification in India. However, solar photovoltaic technology has also been used for providing electricity access in remote, forested habitations and islands. Under the Remote Village Electrification Programme by the Government of India, around 12,000 villages and hamlets have been electrified using renewable energy. The state of Chhattisgarh in Central India has alone been able to electrify around 1,400 remote and forested villages through solar mini-grids. This chapter attempts to examine the development and operation of the solar mini-grid model for enhancing electricity access in India, with special focus on the state of Chhattisgarh. The work, based on extensive literature review, interview with key stakeholders and field visits to selected remote forested villages in the state of Chhattisgarh, shares the experiences and lessons of the solar mini-grid programme for rural electrification in the state by comprehensively analysing multiple dimensions of the programme such as coverage and trend, technical designs, institutional arrangements, financial mechanism and operation and maintenance aspects, which were key to the success of the solar mini-grids. We observe that robust institutional arrangement, strong policy support and an effective maintenance and an oversight mechanism have been the key contributing factors for the success of this initiative.

Energising Rural India Using Distributed Generation: The Case of Solar Mini-Grids in Chhattisgarh State, India

Decentralized electricity systems, especially solar PV mini-grids and off-grid systems have the potential to significantly enhance the standard of living of communities in off-grid areas. Communities living in remote and off-grid locations are often characterized by low access to resources and infrastructure facilities in general, besides the lack of access to electricity. Therefore, it is also observed that quite often, such communities have limited paying capacities and lower energy demand at the outset compared to communities where the grid has been extended. It is therefore important to think carefully about the ways in which end-users of off-grid solar PV pay for the services they are procuring from these systems. In some cases end-users may purchase electricity in kilo-Watt-hours (kWh), and in others, services, in the form of a certain number of hours of light on a daily basis, for example. While standard practices for estimating how much a user should pay for electricity involve the calculation of a Cost of Generation (CoG) and then the tariff, a large number of off-grid projects use different metrics that are not based on the kWhs sold, but rather based on the type and duration of services being provided. Practically, such a system has advantages owing to simpler and lower cost of transactions and the fact that in many cases the transaction mimics those that rural consumers are already familiar with. This chapter aims to provide some insights into the estimation of CoG, and compares this standard methodology of fixing tariffs with an alternative service-based approach. Through the chapter readers will be introduced to basic concepts in the financial analysis of off-grid PV systems, a step-by-step procedure for estimating the CoG and finally a set of case studies to illustrate the value of service-based tariff setting.

P. R. Krithika

Papers

New partnerships and business models for facilitating energy access

Participatory Business Models for Off-Grid Electrification

Energising Rural India Using Distributed Generation: The Case of Solar Mini-Grids in Chhattisgarh State, India

Economics and Management of Off-Grid Solar PV System

Learning from emerging energy innovations in Asia: Contributing to the discourse on an institutional framework for sustainable development