A Techno-Economic Analysis of the Concept
1.1 billion people worldwide (or approximately one in every five people) live without access to electricity. Electrification of geographically remote communities is particularly challenging. These communities exist in both the developed and developing worlds, with different economic development contexts within which electrification must occur.By Mohamed Mamdouh Elkadragy, Karlsruhe Institute of Technology, Germany
Hybrid renewable energy systems have the potential to play a fundamental role in global energy scenarios based on renewable resources, for grid-tied and especially for off-grid applications in remote locations. One of the main obstacles to accelerated expansion of off-grid energy systems is the lack of reliable data relating to system performance combined with economic impacts. This is in large part due to the absence of standardisation in technical and economic analyses. The objective of ping is to understand how the technical, economic (including social), and environmental context in which an off-grid system is deployed affects its economic feasibility and sustainability.
System Topology and Layout
Five major elements are the main building blocks of most of the developed off-grid hybrid renewable energy system (OHRES) topologies. The first element is the renewable electrical energy sources. This is followed by the non-renewable electrical energy sources. Third is the electrical energy storage element and fourth is the supplied electrical load. Fifth is the system control and monitoring. These major elements represent together a complete OHRES which needs to be interconnected (coupled) to provide a physical platform for such elements to interact. The system topology is based on DC coupling; Figure 1 illustrates the general layout of the system including the different components.
Five major elements are the main building blocks of most of the developed off-grid hybrid renewable energy system (OHRES) topologies. The first element is the renewable electrical energy sources. This is followed by the non-renewable electrical energy sources. Third is the electrical energy storage element and fourth is the supplied electrical load. Fifth is the system control and monitoring. These major elements represent together a complete OHRES which needs to be interconnected (coupled) to provide a physical platform for such elements to interact. The system topology is based on DC coupling; Figure 1 illustrates the general layout of the system including the different components.
Affordable Energy for HumanityThe study is carried out within the global initiative Affordable Energy for Humanity (AE4H). AE4H is a global consortium of experts from academia and the private and public sectors that undertakes research, advocacy and knowledge transfer activities to advance Sustainable Development Goal 7 (as declared by the United Nations): to ‘ensure access to affordable, reliable, sustainable and modern energy for all’ by 2030. Participating AE4H researchers advance knowledge across four domains: 1) Generation, Devices, and Advanced Materials, 2) Microgrids for Dispersed Power, 3) Information and Communication Technologies for Energy System Convergence, and 4) Environmental and Human Dimensions of Energy Transitions. AE4H was established in 2015 as a partnership between the University of Waterloo, Canada, and the Karlsruhe Institute of Technology. 140+ experts from 50+ organisations in 20+ countries participate in the initiative in various capacities.
System Design Criteria and ObjectivesThe OHRES of ping has to balance five major objectives:
1) The system has to represent economic feasibility over its lifetime. This does not require by default having the lowest initial cost for the system, but rather ensuring the reliability and sustainability of the system performance and value stream income during the system lifetime.
2) From the technical side, the system should be user-friendly due to the targeted segment of developing economy end users. This feature has to be validated with local case-study tests in target locations to ensure a common understanding of the user needs and knowledge level.
3) Simple system architecture is a key to system reliability and robustness as it will have a major effect on the complexity level of the system operation and maintenance (O&M) activities. This is especially true in off-grid locations where a complicated O&M activity is economically not feasible due to many factors which vary from one off-grid location to another even within the same country. The level of complexity of the system architecture will also have a major influence on one of the challenging aspects of off-grid systems – logistics and system handling for remote areas.
4) Although the architecture system is simple, system reliability and robustness must be considered. This is taken into account to ensure the sustainability of the system performance from a long-term perspective, which will have a major influence on the system economics. In addition, building the trust between the end consumers and the OHRES is elementary in developing country markets.
5) Safety is a non-negotiable criteria for system design, especially for electrical energy systems. The system takes this into consideration by paying attention to the safety-related aspects of both components and the system.
Case Studies and System-Related Aspects
The research compares an OHRES deployed in two case studies with contrasting economic and environmental conditions. The selected locations are a private household in British Columbia, Canada, and a school in Jinja, Uganda, in sub-Saharan Africa. An OHRES will be installed in each location combined with an off-grid remote system monitoring and weather station (SMWS) as illustrated in Figure 2. The main components of the SMWS include the following:
The research compares an OHRES deployed in two case studies with contrasting economic and environmental conditions. The selected locations are a private household in British Columbia, Canada, and a school in Jinja, Uganda, in sub-Saharan Africa. An OHRES will be installed in each location combined with an off-grid remote system monitoring and weather station (SMWS) as illustrated in Figure 2. The main components of the SMWS include the following:
- Self-powered commercial weather station.
- Hall effect sensors (voltage/current measurement).
- Controller and data acquisition unit.
- GSM modem or Internet router.
Both case studies were selected taking into account the commonalities between sites regarding technical performance specifications such as expected range of peak loads and off-grid system size. A semi-identical system design is applied by using similar technologies with many common components for both case studies. This allows a contrastive and reflective system analysis.
OHRES Techno-Economic Modelling and Data Analysis Platform
The role of the off-grid system data analysis platform (OSDAP) is to analyse the primary data generated through the local SMWS. The Python-based platform analyses the weather data, field system measured values and the data generated via system components, through applying handling techniques such as data clustering, filtering, null elimination, and visualisation. However, the cornerstone of the platform is a data reliability validation which is used for the modelling of hybrid generation systems, optimising off-grid systems and generating techno-economic models. The OSDAP architecture is illustrated in Figure 3.
The role of the off-grid system data analysis platform (OSDAP) is to analyse the primary data generated through the local SMWS. The Python-based platform analyses the weather data, field system measured values and the data generated via system components, through applying handling techniques such as data clustering, filtering, null elimination, and visualisation. However, the cornerstone of the platform is a data reliability validation which is used for the modelling of hybrid generation systems, optimising off-grid systems and generating techno-economic models. The OSDAP architecture is illustrated in Figure 3.
Uganda Case-Study System Phase 1 DeploymentOne of the most critical prerequisites for a successful off-grid system design is a very early site survey due to the fact that each off-grid location is unique. This aspect is taken into consideration in the study, especially for the developing country case study in Uganda where there is not enough information and data available. In early 2018 a site visit was done to the case-study location in Uganda. The visit included several activities and objectives, each objective having a list of needed actions in order to achieve the needed result (the detailed action plan is not shared here). Figure 4 shows the deployment of the weather station and the remote data acquisition system, including a GSM modem for providing Internet connection in Uganda. The weather station is installed for the hot-run test in a secure testing location near to its planned final installed location. It is planned that the weather station will be transferred to the final installation location once the school is in operation.
The data on the data acquisition and control unit can be accessed and downloaded to the databank using an online Web portal. Figure 5 shows a real example of how the data is illustrated on the Web portal based on the data transferred from the weather station in Uganda. The SMWS and the data portal are developed in cooperation with the institute’s industrial partner Infinite Fingers.
Major Lessons Learned for Phase 1 System Deployment in Uganda
Lesson 1: Test as Much as Possible Prior to Shipment
When possible, it is important to undertake pre-commissioning and cold-run tests for different OHRES parts in a controlled environment (laboratory test, factory test or local prototypes) before sending the parts to the final off-grid location. This minimises the likelihood of problems in the final remote location where there is almost no technical support or room for complicated troubleshooting.
When possible, it is important to undertake pre-commissioning and cold-run tests for different OHRES parts in a controlled environment (laboratory test, factory test or local prototypes) before sending the parts to the final off-grid location. This minimises the likelihood of problems in the final remote location where there is almost no technical support or room for complicated troubleshooting.
Lesson 2: Some Components Would Still Represent a Technical Challenge
For some of the OHRES parts, it is not possible to perform pre-commissioning and testing before sending them off-grid. Even some of the pre-tested components can represent a challenge for commissioning on-site. For example, in this system such components included the GSM modem, which provides the Internet connection for the remote data stream from the remote location in Uganda to the database in Germany. Such components represent sources of very high risk to the success of achieving the objective of having an off-grid running system with remote monitoring. Unfortunately, there are no clear risk mitigation methodologies available for such risk sources due to the general lack of standardisation in the off-grid sector, in addition to the lack of enough publicly-shared practical field experience.
For some of the OHRES parts, it is not possible to perform pre-commissioning and testing before sending them off-grid. Even some of the pre-tested components can represent a challenge for commissioning on-site. For example, in this system such components included the GSM modem, which provides the Internet connection for the remote data stream from the remote location in Uganda to the database in Germany. Such components represent sources of very high risk to the success of achieving the objective of having an off-grid running system with remote monitoring. Unfortunately, there are no clear risk mitigation methodologies available for such risk sources due to the general lack of standardisation in the off-grid sector, in addition to the lack of enough publicly-shared practical field experience.
Lesson 3: Handling Logistics in an Effective Way
System logistics could be an underestimated aspect in theoretical evaluations of off-grid electrical systems; this is due to the lack of practical experience in most of the research work done in this area so far. In practice, logistics play a major role in system deployment feasibility and represent a major influence on the economics of the off-grid system.
System logistics could be an underestimated aspect in theoretical evaluations of off-grid electrical systems; this is due to the lack of practical experience in most of the research work done in this area so far. In practice, logistics play a major role in system deployment feasibility and represent a major influence on the economics of the off-grid system.
Lesson 4: Having the Right Local Main Project Partner
One of the most critical learning lessons (which is also a source of high project risk) is having a main reliable local partner who represents the main access point to the targeted local community. Such a partner undertakes most of the local coordination roles and support activities on the ground. One of the common partner types in developing countries is non-governmental organisations (NGOs). Most active local NGOs in developing countries know most of the real local needs and have a solid foundation of trust and contacts in their service area. Selection of a reliable and trusty NGO is not as easy as it sounds. If the NGO does not share the same general vision of the project and does not have a real need for the type of development proposed within the project scope, it will not be possible to establish a productive partnership. On the other hand, if the project represents one of the core needs or activities of the NGO, the reflection on results will be remarkable.
One of the most critical learning lessons (which is also a source of high project risk) is having a main reliable local partner who represents the main access point to the targeted local community. Such a partner undertakes most of the local coordination roles and support activities on the ground. One of the common partner types in developing countries is non-governmental organisations (NGOs). Most active local NGOs in developing countries know most of the real local needs and have a solid foundation of trust and contacts in their service area. Selection of a reliable and trusty NGO is not as easy as it sounds. If the NGO does not share the same general vision of the project and does not have a real need for the type of development proposed within the project scope, it will not be possible to establish a productive partnership. On the other hand, if the project represents one of the core needs or activities of the NGO, the reflection on results will be remarkable.
Lesson 5: Local Community Involvement
In remote areas, local communities are either a support for or a risk to off-grid projects. The involvement of the local community in the early stages of a project (even in the project planning stages if possible) increases the chances of gaining its full support during the project life cycle and even can be the only guarantee of the project’s sustainability in some cases. What was also learned is that involvement of the local community should be done with a certain respected hierarchy. This was achieved through project information gatherings arranged by the institute’s local main NGO partner through the village mayor who addressed the invitation to the local community and government.
In remote areas, local communities are either a support for or a risk to off-grid projects. The involvement of the local community in the early stages of a project (even in the project planning stages if possible) increases the chances of gaining its full support during the project life cycle and even can be the only guarantee of the project’s sustainability in some cases. What was also learned is that involvement of the local community should be done with a certain respected hierarchy. This was achieved through project information gatherings arranged by the institute’s local main NGO partner through the village mayor who addressed the invitation to the local community and government.
Conclusion and Outlook
The comparative techno-economic assessment of the case studies in Canada and Uganda will provide a clear understanding of OHRES behaviour in two contrasting contexts. This will generate a precise understanding of how the OHRES economics are affected by the technical and environmental aspects. This will support the deployment of such systems not only in similar environments to the ones within the research scope, but also any other location within the extreme boundary conditions of the study, theoretically the whole world.
The comparative techno-economic assessment of the case studies in Canada and Uganda will provide a clear understanding of OHRES behaviour in two contrasting contexts. This will generate a precise understanding of how the OHRES economics are affected by the technical and environmental aspects. This will support the deployment of such systems not only in similar environments to the ones within the research scope, but also any other location within the extreme boundary conditions of the study, theoretically the whole world.
Biography
Mohamed Mamdouh Elkadragy is a renewable energy scientist with more than five years of industrial and applied research related professional experience on an international scale. He holds a master’s degree in Renewable Energy (with excellence), and a BSc in Electrical Engineering. Currently working as a research scientist at the Karlsruhe Institute of Technology, the main focus of his research is the development of renewable energy storage systems, solar photovoltaics, wind and renewable hybrid systems.
Mohamed Mamdouh Elkadragy is a renewable energy scientist with more than five years of industrial and applied research related professional experience on an international scale. He holds a master’s degree in Renewable Energy (with excellence), and a BSc in Electrical Engineering. Currently working as a research scientist at the Karlsruhe Institute of Technology, the main focus of his research is the development of renewable energy storage systems, solar photovoltaics, wind and renewable hybrid systems.
