18Off-Grid and Edge-of-Grid Photovoltaic Systems

Task Managers

Mr. Christopher MARTELL

Task 18 will deal with off-grid electrical systems and edge-of-grid electrical systems which include photovoltaics.

Off-grid refers to electrical systems or grids which are remote from the main electrical grid. Often these grids are state owned or regulated electrical infrastructure. This is not to say that an off-grid system cannot be state owned or regulated, but that an off-grid system stands alone from the principal infrastructure of a, typically, state owned or regulated grid.  Examples of an off-grid system include:

  • A single dwelling, powered by a system which includes photovoltaics
  • An islanded mini-grid, powered by renewable generation which includes photovoltaics
  • A power system which provides electricity to an entire island community consisting of hundreds of people
  • A communications node located in a remote area
  • A temporary work site such a remote mine

Edge-of-grid refers to areas where the main electrical grid may be unstable or not fit for purpose and the use of systems which include photovoltaics may serve as a solution. Edge-of-grid areas are often exposed to similar issues as off-grid areas with regards to reliability, resiliency and security and photovoltaics may provide part of the solution for these areas. Examples of edge-of-grid systems include :

  • Grid connected communities which are located hundreds of kilometres away from principal electrical infrastructure
  • A single, grid connected asset which is located in an area which is expensive for a utility company to service
  • A grid connected microgrid where the grid connection provides poor power quality and/or poor reliability


Task 18 will dedicate the majority of its efforts to larger and more complex off-grid and edge-of-grid system issues.  IEA PVPS Task 11 addressed many of the issues arising at the time for smaller off-grid systems, however the industry has moved significantly since the closure of Task 11:

  • Off-grid and Edge-of-Grid systems have grown in capacity to multi-megawatt scale
  • The control systems, data granularity and field sensory data gathered and used to inform Off-grid and Edge-of-Grid systems is highly complex and often incorporates Artificial Intelligence decision making.
  • Off-Grid and Edge-of-Grid systems may be financed via roll out of programs


The objective of Task 18 is to find the technical issues and barriers which affect the planning, financing, design, construction and operations and maintenance of off-grid and edge-of-grid systems, especially those which are common across nations, markets and system scale, and offer solutions, tools, guidelines and technical reports for free dissemination for those who might find benefit from them.

The issues that will be focused on with regard to off-grid and edge-of-grid photovoltaic system will centre on:

  • Reliability: A system that has the ability to generate and distribute energy to meet the demands of those connected with a high degree of confidence
  • Resiliency: A system that can withstand or recover quickly from natural disasters, deliberate interference or accidents
  • Security: A system that is sustainability affordable and provides an uninterrupted supply of energy which adequately meets the associated demand.

Task 18's current phase began in 2019, ends in 2023 and activities are organized as follows

1Subtask 1 : Technical Innovations in Off-Grid and Edge-of-Grid PV Systems

This activity will broadly research and summarise the significant innovation and increased sophistication of off-grid and edge-of-grid systems over the past 8 years (since the closing of Task 11).  A particular focus will be given to:

  • lithium ion batteries in off-grid and edge-of-grid applications
  • compatibility of off-grid systems as they grow and consider interconnection
  • Metering and monitoring technology
  • Mini-grid data analysis and control systems
  • Technology used in 100% renewable energy fed grids

2Subtask 2 : Financial Optimisation of Hybrid Off-Grid Systems

  • Activity 1: Definition of Constraints and Variables for Hybrid System Optimisation
  • Activity 2: Triple Bottom Line (TBL) Analysis
  • Activity 3: Generator Mixture Modelling

3Subtask 3 : Operations and Maintenance of Remote Area Power Systems

  • Activity 1: Monitoring and Control for Active System Operations and Maintenance
  • Activity 2: Active System Operations and Maintenance Modelling
  • Activity 3: Sustainable Training Programmes for Remote Area Maintenance

4Subtask 4 : Cooperation and Dissemination

The goal of this subtask is to reach a maximum level of task work product dissemination, to cooperate with Industry Associations, Consultancies, Academia and other industry participants and to tailor the workings of Task 18 in order to limit any redundancy with other groups and/or increase the value of Task 18 work output for other groups.  Key groups for collaboration are other IEA PVPS Tasks, the International Renewable Energy Agency (IRENA) and Mission Innovation (a European Union initiative borne out of COP21)

This activity will distribute reports, models and tools through partner newsletters, workshops, webinars and presentations. The Task will also make use of social media group work platforms and communication platforms to achieve deliverables and foster engagement.  The Task also has its own website which will be used as a repository for all meeting minutes, agendas, progress updates, etc.  The IEA PVPS will, of course, be treated as the official repository of all finalised Task 18 work output

Task 18 Reports