2019/106 Supported by K NKONW A A WELDEGDEG E OL N ONTOET E S ESREI R E ISE S F OFRO R P R&A C T HTEH E NEENREGRYG Y ETX ITCREA C T I V E S G L O B A L P R A C T I C E THE BOTTOM LINE Planning Models for Electricity Access: The expansion of access to electricity remains an urgent Where Do we Go from Here? international goal (IEA and others 2019). Recent progress in expanding access has depended What is the best way to expand access to electricity? limited coordination between models, which hinders holistic planning of electricity systems. Access could be advanced by combining the on the use of planning models Closer integration of two schools of modeling two types of models. that fall into two broad categories: may be the solution This brief is aimed at power system planners, as well as project (i) power-flow models and (ii) Nearly 840 million across the globe still lack access to electricity, managers and task team leaders in Sub-Saharan Africa and South newer GIS-based models. Tighter a majority of them in Sub-Saharan Africa (World Bank 2019). While Asia, who could benefit from deploying integrated electricity access integration of the two categories, there is no certainty that Sustainable Development Goal 7—universal planning in their projects. Our objective is to elicit opinions on the the authors believe, may facilitate access to modern energy by 2030—will be achieved, the access value proposition of an enhanced and integrated electricity access better planning and so accelerate gap is slowly closing through innovation and diligent planning (Leke, planning model. If the proposition commands interest, we will the expansion of access. If readers Chironga, and Desvaux 2019). Progress is possible, as Kenya has develop a prototype and undertake a case study to explore whether agree, the authors will develop a demonstrated. Kenya’s electricity access rate has nearly tripled in the the access solutions derived from the integrated model differ from prototype and undertake a case past decade to nearly 75 percent (Njugunah 2018). Kenya has more the results of existing models already in use in World Bank projects. study to explore whether the access solutions derived from the than doubled its grid connections in a span of just four years. Off-grid integrated model differ from the expansion has also been rapid. What distinguishes the two sets of access results of existing models already Most success stories are based on the application of one planning models? in use in World Bank projects. or more of four prevailing models for planning the expansion of access. This brief reflects on the state of the art of those models They were devised at different times for and discusses an analytical development that may make them more different purposes Rahul Srinivasan is a holistic and effective. Most efforts to expand access to electricity are based on a power consulting energy specialist Access planning models fall into two broad categories: (i) old system planning model, a GIS-based planning model, or one of each. at the World Bank. school models based on power flow, and (ii) their new school Although both groups of models aim to meet demand for access at counterparts based on geographic information systems (GIS). At the lowest cost, the two types are different. present, the latter do not use an integrated power-flow model. Here Power system planning covers upstream generation and trans- Debabrata we discuss the pros and cons of the two categories and discuss the mission planning along with incremental expansion of distribution Chattopadhyay possibility of bringing them closer together to accelerate growth in systems. This conventional form of planning, widely used by utilities, is a senior energy specialist access to electricity. entails load-flow analysis to determine network configuration, the at the World Bank. Currently, utilities and governments use both types of models to length of distribution feeders, conductor specifications, and the plan and design their access projects. The problem, however, is the resultant power flows and voltages. 2 P l a n n i n g M o d e l s f o r E l e c tri c it y A c c ess : W h ere D o we G o f r o m Here ? Power system planning models have several salient character- Distribution utilities in all countries that can afford load-flow tools istics. They are bottom-up efforts—that is, the first step is usually to and know how to use them still plan their systems using these tools, pull together demand estimates from the bottom up. They are well turning to GIS systems only to present the results. The National Rural suited for incremental expansion of the network at granular levels Electric Cooperative Association (NRECA) in the United States is a of distribution. By contrast, they are not suitable for a higher-level good example. For NRECA, the WindMil load-flow model remains Access planning models study of a wider region with large off-grid areas. They align closely the central tool, with GIS aiding visualization. Innovations in GIS have fall into two broad with the practical realities of the system—and they are well known to made visualization more appealing and thus enhanced utilities’ abil- distribution system engineers. ity to translate intuitive understanding of the system into quantitative categories: old school GIS-based planning, a relatively recent innovation, constitutes a inputs on where and how the network should be expanded. As GIS models based on power stand-alone tool for analyzing access at the distribution level. This tools become more sophisticated, they will be even more valuable flow, and their new school form of planning is used by governments and the private sector, as supplements to the load-flow models that drive electricity access counterparts based on especially in the off-grid energy space. For example, NASA’s night planning. light imagery, originally developed for weather prediction, is being However, as universal access to electricity has become a geographic information piloted for many innovative applications, including energy infrastruc- paramount goal for governments and development institutions, systems. Access could be ture planning (NASA 2017). stand-alone GIS-based models that add intelligence and sophistica- advanced by combining the Stand-alone GIS models are more flexible than a power system tion to existing GIS tools have come to be widely used. Commonly two types. planning model—they can proceed from the bottom up or from the used on the national level, GIS models have long been adaptable to top down. In the course of their development, they have become more granular levels where the requisite data are available. In recent well aligned with off-grid systems and distributed energy resources years, in response to need, GIS models requiring less extensive data (DER), especially renewables, which have been among the key have evolved for use in contexts where access to data is limited, as drivers of the development of GIS models. They are often used for is the case in many of the countries where electricity access projects high-level studies, especially when other forms of data are limited. are designed and implemented. Their key shortcoming is that they do not embed power-flow But although the ability to add multiple layers of population, constraints and hence are not a mainstream tool for utilities. income, and network data to a geospatial model greatly enhances While the two types of model can and should be complemen- the understanding of the system being modeled, stand-alone tary, this is largely not the case, though there is some degree of GIS-based systems are often used, unadvisedly, to make decisions complementarity in peripheral features such as visualization and on where and how access should be expanded in the absence of geo-referenced data. the larger picture of the power system that load-flow analysis can Utilities’ approaches have not changed much since the 1970s. provide. In other words, power system modeling and stand-alone Planners in the seventies typically used a map, scattered data on GIS-based modeling are not being used in a complementary manner population, and rules of thumb to decide whether to add a new to achieve holistic access planning. This lack of coordination, covered substation to connect new customers (or to section load among in a previous Live Wire (Chattopadhyay, Jordan, and Kitchlu 2014), is existing substations), to decide on the length of feeders, or to more relevant than ever. undertake reactive compensation, among other tasks. This would be followed by a load-flow analysis to check the feasibility of the system and fine-tune the solution. 3 P l a n n i n g M o d e l s f o r E l e c tri c it y A c c ess : W h ere D o we G o f r o m Here ? How do existing planning models compare? NRECA methodology. After georeferencing the existing electrical system, the NRECA model evaluates the technical performance The models differ in their geographic focus, their of each distribution feeder using Milsoft’s WindMil, a commercial data sources, and their proprietary status power-flow software package, or NRECA modules devoted to load This section discusses existing models used in electricity access flow, voltage profile, and technical losses. A commercial evaluation Our objective is to elicit planning (figure 1). Planning occurs at all levels, from the national is also performed. Similarly, technical and commercial analyses are opinions on the value level down to collections of villages. The figure specifies the geo- conducted for line extension based on load, number of customers, graphic scope of the models shown. Selection of a model is also and prospective increases in energy consumption. The NRECA proposition of an enhanced governed by the availability of data. It is important to remember that methodology, which is well suited to detailed distribution planning at and integrated electricity granular levels, reflects utilities’ focus on traditional power system the selection of a model is shaped both by the objective of the study access planning model. (i.e., its geographic scope) and the availability of data. The models are modeling. summarized below. Figure 1. Comparison of access planning models—from the country level to groups of villages National access Province/district/zonal Granular distribution planning Model Open source planning access planning (for e.g., village level) NRECA NO MIT REM NO Columbia YES Earth Institute KTH OnSSET YES Note: Solid line indicates that the entire geographical spectrum between the circles is covered. Dotted line for MIT REM model indicates that the distribution network planning component is not fully integrated into the model. See discussion of Reference Network Model in text. 4 P l a n n i n g M o d e l s f o r E l e c tri c it y A c c ess : W h ere D o we G o f r o m Here ? MIT’s Reference Electrification Model (REM). In the REM model, Could power system planning and GIS-based planning GIS is used to ascertain unknown attributes of households (e.g., size) be better integrated? If so, how? in particular clusters, as well as the geographical characteristics of those clusters. Household census data, satellite image processing, Fusing the two paradigms promises substantial and crowdsourced pinpointing of users are some of the methods benefits, and doing so is feasible As universal access used to obtain information. Based on this information, the REM The foregoing review of power system planning models and to electricity has model compares various energy technologies and layouts to identify sophisticated stand-alone GIS-based models suggests the following an optimal power system design for the area. become paramount questions: The model compiles customers’ load profiles, which can be for governments • Is there a need to bring the two paradigms closer? estimated using their average income level and service tier. It can • If so, do analytical frameworks exist to accomplish the task? and development be used by planners (including distribution companies, policymak- institutions, stand-alone ers, regulators) to estimate electrification costs and appropriate Well-integrated planning models can help cover the whole plan- electrification modes (network extension, isolated mini-grids, and GIS-based models that ning spectrum—from the national level down to granular distribution stand-alone systems) at a regional level. Additionally, engineers and add intelligence and at the village level. GIS electrification plans made at the distribution designers intending to electrify specific areas can use it to make level should not be used in isolation; instead, power system models sophistication to existing design decisions that appropriately balance level of service and should be used to synchronize generation and transmission planning GIS tools have come to be costs. The REM model thus includes both power system planning and with expansion at the distribution level. Planning engineers have GIS and can be used iteratively with the Reference Network Model widely used. retained their faith in power-flow models such as Siemens’s PSS®E (RNM), a distribution network planning model that is not (yet) fully (Power System Simulation for Engineering) that have a solid engi- integrated in REM. neering foundation. Integration of models is critical to ensure that Columbia Earth Institute methodology. The model’s inputs include investment plans are realistic and accurately reflect the costs that electricity demand, costs, and geographic characteristics. Its spatial utilities face in practice. nature enables the presentation of existing electricity network and Well-integrated models also ensure that the network is efficient, population distributions, which form the basis for future expansion secure, and resilient. decisions. While it does not build in load-flow analyses, the model Achieving efficiency with respect to technical characteristics acknowledges that these are required for holistic access planning, (e.g., low levels of loss) and cost may require that aspects of the especially at granular levels. existing network be carefully redesigned as an integral part of the KTH OnSSET. The KTH model also focuses largely on GIS planning. expansion process. A common deficiency of distribution network Its overall aim is to link GIS and energy planning by (i) utilizing the expansion in developing countries is that the medium- and low-volt- open source GIS datasets that have recently become available age network is repeatedly extended without regard to the possibility to estimate the technical and economic potential of local energy that some existing feeders should be upgraded before they are resources, and (ii) developing and applying a geospatial electrification extended. There is almost no consideration of such questions in a toolkit that yields the mix of technologies needed to secure universal typical stand-alone GIS-based model. Also, GIS-based models do not electricity access at the least cost. This model is well aligned with take into account central generation capacity or the implications for efforts to exploit DERs, but it does not include much power system the grid of increasing that capacity. planning and has limited value for access planning at granular levels. 5 P l a n n i n g M o d e l s f o r E l e c tri c it y A c c ess : W h ere D o we G o f r o m Here ? A secure network has sufficient capacity and redundancy to • Increase the emphasis on network reliability and security absorb contingencies. This issue, too, is typically ignored by stand- considerations, to push planners toward a better balance of DER alone GIS-based models. and grid-supply options. Finally, a resilient network is one designed to withstand natural • Promote better coordination between distribution and upstream disasters. generation/transmission models. Well-integrated planning Because grid expansion at the distribution level must be coor- models can help cover dinated with generation and transmission planning, the two models The first option could entail a significant investment in model are complementary—one model centered on load flow and used to development. Integrating load-flow equations into a GIS-based model the whole planning expand the grid incrementally; and a GIS-based model at the other may pose significant data and computational issues. Simpler and spectrum—from the end that closely aligns with DERs. The complementarity is particularly more expedient options may include better coordination between (i) national level down to relevant in light of planners’ concerns to maximize system reliability GIS-based and load-flow models (following the example of MIT’s REM granular distribution at the and resilience when expanding existing networks, as opposed to model and, to a lesser extent, the NRECA model) or (ii) distribution emphasizing off-grid means to expand access in isolation from planning and upstream models. village level. Integration of attention to the grid. Of course, both grid and off-grid expansion are Choices will have to be made among these multiple possibilities. models is critical to ensure important to close the electricity access gap, but an integrated model The key objective of this brief is to seek opinions on relative priorities. that investment plans are offers the best means of determining where and how each should be If readers can provide evidence that access programs have been realistic and accurately expanded. affected by lack of supply at the transmission substation level, Having established the merits of bringing the two paradigms this will argue for a better coordination between generation and reflect the costs that closer, we now consider how this can best be done. transmission master planning. If evidence surfaces of persistent utilities face in practice. Sophisticated stand-alone GIS tools are still largely used by uni- problems with underestimation of investment needs following use of versities and have not yet been fully embraced by utilities’ planning GIS-based models, the priority will be to enhance the technical rigor groups, except in capacity building exercises undertaken by donor of the models. Some of the open questions we hope to resolve are: agencies. Practicing engineers and consulting firms continue to rely • The value proposition (cost, effectiveness) of an integrated model on traditional load flow–based tools for power system analysis. But for utilities in developing countries now we know that a well-integrated model can advance access • The feasibility of upgrading existing models (integrating RNM into planning across the geographical spectrum (from the national to the REM) to improve their usefulness in securing holistic outcomes village level). The residual problems are (i) that licenses for models • Computational feasibility and the maximum network size a given such as NRECA and REM can be expensive and (ii) that the RNM model can handle distribution network planning model is not fully integrated into MIT’s • Accessibility and financial feasibility of integrated models for REM model. Until these obstacles are surmounted, one or more governments and utility planners. of the following tactics can be employed to take advantage of the benefits of combining the two planning paradigms. One can: • Embed one of the variants of load-flow models (three-phase AC load flow, single-phase AC load flow, DC load flow) into a GIS-based model. Even the simplest version would substantially improve the current state of the GIS models and hence improve their compatibility with pure load-flow models. 6 P l a n n i n g M o d e l s f o r E l e c tri c it y A c c ess : W h ere D o we G o f r o m Here ? What are the next steps to better integrate power References MAKE FURTHER system planning and GIS-based planning? Chattopadhyay, Debabrata, Rhonda Jordan, and Rahul Kitchlu. 2014. CONNECTIONS “Planning for Electricity Access.” Live Wire 2014/35, World Bank, Several opportunities are within our grasp Washington, DC. http://hdl.handle.net/10986/20596 Live Wire 2014/9. “Tracking Access to Electricity,” by Sudeshna Ghosh The access planning exercises and least-cost electrification studies IEA (International Energy Agency), International Renewable Energy Banerjee and Elisa Portale. conducted by the World Bank have generally been expensive. The Agency, United Nations Statistics Division, World Bank, and World collection of primary data has accounted for a large share of this Health Organization. 2019. Tracking SDG 7: The Energy Progress Live Wire 2014/16. “Capturing the Multi-Dimensionality of Energy expense. However, the advantages of building the Bank’s in-house Report 2019. World Bank, Washington, DC. http://documents. Access,” by Mikul Bhatia and Nicolina capacity for cheaper and better modeling can be significant. The past worldbank.org/curated/en/517781558037625254/Main-Report Angelou. five years have seen some encouraging developments, including Leke, Atsa, Mutsa Chironga, and Georges Desvaux 2019. “The Live Wire 2014/20. “Scaling Up Access the global access planning tool developed by the World Bank’s Innovations Closing Africa’s Electric Power Gap.” Harvard to Electricity: The Case of Lighting Geospatial Operation Support Team (World Bank 2018), the Global Business Review (online), January 16. https://hbr.org/2019/01/ Africa,” by Daniel Murphy and Arsh Electrification Platform helmed by ESMAP , and significant coun- the-innovations-closing-africas-electric-power-gap Sharma. try-level work done by regional teams with the participation of Bank NASA (National Aeronautics and Space Administration). Live Wire 2014/35. “Planning for staff and consultants. https://www.nasa.gov/feature/goddard/2017/ Electricity Access,” by Debabrata Moving forward, some key recommendations for World Bank new-night-lights-maps-open-up-possible-real-time-applications Chattopadhyay, Rahul Kitchlu, and Rhonda L. Jordan. teams are: Njugunah, Margaret. 2018. “Kenya Has Highest Access to Electricity • Explore practical ways to integrate load-flow modeling and in East Africa: WB Research.” Capital Business (online). May 8. Live Wire 2015/51. “Scaling Up Access GIS-based modeling and make the resulting model accessible https://www.capitalfm.co.ke/business/2018/05/kenya-has-high- to Electricity: Emerging Best Practices for Mini-Grid Regulation,” by Chris and economical for governments and utility planners in client est-access-to-electricity-in-east-africa-wb-research/ Greacen, Stephanie Nsom, and Dana countries. One practical way of arriving at this outcome would World Bank 2019. “More People Have Access to Electricity Rysankova. be to reassess the priorities of the Bank’s task team leaders and Than Ever Before, but World Is Falling Short of Sustainable power system experts. Energy Goals.” Press release, May 22, Washington, DC. http:// • Collaborate with universities to develop integrated models that www.worldbank.org/en/news/press-release/2019/05/22/ leverage innovations, new data, and new tools and that can be tracking-sdg7-the-energy-progress-report-2019 applied to the full geographic spectrum, from national planning World Bank 2018. “Geospatial Operations Support Team to granular distribution planning at the village level. at the World Bank.” Brief, December 6, Washington, • Offer workshops and training programs to build technical DC. https://www.worldbank.org/en/research/brief/ planning capacities within the World Bank, governments, utilities, geospatial-operations-support-team-at-the-world-bank universities, and the private sector. The authors would like to thank Rhonda Jordan, Nicolina Lindblad, and Shaky Sherpa for their help in preparing the section on existing access planning models and the associated graphic. They also thank Claire Nicolas, Christopher James Arderne, Chiara Rogate, Samuel Oguah, and Joern Huenteler for their valuable contributions. The authors are grateful to Dana Rysankova, Raihan Elahi, and Zubair Sadeque for their review comments. Get Connected to Live Wire Live Wire briefs are The Live Wire series of online knowledge notes, an initiative of the World Bank Group’s designed for easy reading Energy and Extractives Global Practice, offers rich insights from project and analytical work on the screen and for done by the World Bank Group. downloading and self-printing “Live Wire is designed in color or black and white. Every day, Bank Group experts apply their knowledge and expertise to solve practical problems in for practitioners, policy client countries. Live Wire captures the rich insights gained in the field, allowing authors to share For World Bank Group their findings with other practitioners, policy makers, and planners. employees: Professional makers, and planners printing can be done on a inside and outside the Shouldn’t you be connected to Live Wire? customized basis for meetings and events by contacting World Bank Group. Since 2014, the 80 briefs in the series have dealt with vital topics such as energy demand and GSDPM Customer Service It is a resource to supply; renewable energy; energy efficiency; energy policy; economic growth; environmental Center at (202) 458-7479, or protection; climate change mitigation; power systems; rural and urban development; access to share with clients, sending a written request to energy; infrastructure economics; private sector participation; access to finance; and regulation. cgsdpm@worldbank.org. colleagues, and • Topic briefs offer technical knowledge on key energy issues. counterparts.” • Case studies highlight lessons from experience in implementation, often with insights from private sector engagement. • Briefs on global trends provide analytical overviews of key energy data and developments. • Bank views portray the Bank Group’s energy and extractives sector activities. The format is accessible, rigorous, and concise enough to be easily shared. The 4–12 pages of each brief make ample use of graphics. Briefs are peer-reviewed by seasoned practitioners within the World Bank Group and professionally edited and produced. While their main channel of dissemination is online, Live Wires are available in print-ready files for specific client needs. Please visit the World Bank Group’s Open Knowledge Repository to browse the Live Wire collection and download the issues important to you: www.worldbank.org/energy/livewire An invitation to World Bank Group staff Contribute to If you can’t spare the time to contribute to Live Wire but have an idea for a topic or case we should cover, let us know! We welcome your ideas through any of the following channels: Do you have something to say? Via the Communities of Practice Say it in Live Wire! in which you are active By participating in the Energy Those working on the front lines of energy and extractives development in emerging economies and Extractives Global Practice’s have a wealth of technical knowledge and case experience to share with their colleagues but may annual Live Wire series review not have the time to write for publication. meeting Live Wire offers prospective authors a support system to make it easier to share their knowledge: By communicating directly with the Live Wire team • Staff from the Energy and Extractives Global Practice are available to assist operations staff in (contact Jonathan Davidar, drafting Live Wire stories. jdavidar@worldbankgroup.org) • User-friendly guidelines help authors mold their contribution to the expectations of the Live Wire audience. • A professional series editor ensures that the writing is punchy and accessible. • A professional graphic designer assures that the final product looks great— a feather in your cap! Since 2014 the Energy and Extractives Global Practice has produced 80 Live Wire briefs under the bylines of 240 staff authors. Live Wire briefs have been downloaded thousands of times from the World Bank’s Open Knowledge Repository and circulated in printed form for countless meetings and events. Your Name Here Become a Live Wire to Live Wire aims to raise the profile author and contribute , your practice and career of operational staff with practical while mo del ing goo d knowledge to share—wherever they “knowledge citizenship” are based. by sharing your insights ers. and experience with oth