Energy access constitutes one of the fundamental building blocks for economic growth as well as social equity in the modern world. Access to sustainable energy is needed to achieve sustainable development. A microgrid should not be seen as a competitor to the centralized grid but as a complement.

Through examination of several implemented cases from different parts of the world the following topics are considered:

• Analysis of the interaction between centralized grids and microgrids
• Analysis of stakeholder decision parameters for electrification
• Analysis of design differences and requirements for microgrids, depending on the intended purpose and the need of the end customers

It is determined that good planning, suitable requirements and clear regulations for microgrids (in relation to centralized grids) limits the risk of stranded assets and enables better business cases for the involved stakeholders.
The paper is based on the discussion paper The role and interaction of microgrids and centralized grids in developing modern power systems – A case review publiced by ISGAN (International Smart Grid Action Network) Annex 6: Power T&D Systems.

Evolutions in the grid operation sector will require an ever closer cooperation between Transmission System Operators and Distribution System Operators. The current interaction between TSOs and DSOs has been investigated for six specified grid operation challenges, and possible future ways of cooperation have been identified. Technical aspects as well as policy aspects have been taken into account.
The technical requirements for an evolved interaction between TSOs and DSOs can be met using available technology. However, several non-technical issues and points of discussion have been identified, of which some are related to the regulated environment grid operators are working in.

A growing amount of variable renewable energy generation, coupled with increasing consumer involvement through micro generation and flexible demand management, challenge the old ways of planning, operating, and investing in power systems.

In most developed countries, the existing electric infrastructure and workforce is rapidly aging, while in many developing countries, demand for electricity is rapidly rising. Across this landscape of change, it is crucial for policy-makers to understand the synergies between grids and information and communication technologies. Only smart and strong grids will connect people with reliable clean energy. This paper presents a part of the work being done within ISGAN Annex 6 on Power T&D Systems. International Smart Grid Action Network (ISGAN) is an initiative within the Clean Energy Ministerial (CEM) and an Implementing Agreement within the International Energy Agency (IEA). For more information please go to www.iea-isgan.org, or www.cleanenergyministerial.org/Our-Work/Initiatives/Smart-Grid.

This work involves the major economies and consequently major energy users in the world and is addressing the challenges for a secure and clean energy system including the concerns put forward by Intergovernmental Panel on Climate Change (IPCC). IEA publish regularly the reports World Energy Outlook (WEO) and Energy Technology Perspectives (ETP). In addition IEA has published a number of Technology Roadmaps, e.g. on Smart Grids, Wind Energy, Concentrating Solar Power (CSP), Solar PV Energy and Energy Storage. All scenarios showed by IEA are indicating a further increase of electricity as energy carrier both due to the integration of Renewable Energy Sources (RES) and due to increased electricity consumption in many countries, besides common applications also due to increased use of home electronics, heat pumps, air conditioning and electrical transportation (e.g. electrical vehicles, high speed trains). Increased variable electricity production (large scale and distributed) will require mitigation from storage and/or demand response. This will give further demands for capacity, flexibility and reliability of the future power T&D system.

Energy access constitutes one of the fundamental building blocks for economic growth, as well as social equity, in the modern world. Access to sustainable energy is needed to achieve sustainable development. This paper serves as an input document to the global discussion on how to reach the UN goal of “Sustainable Energy for All”, by sharing case study knowledge in the field. The following topics are considered through the examination of several implemented cases from different parts of the world:

• Analysis of the interaction between centralized grids and microgrids.
• Analysis of stakeholder decision parameters for electrification through extension of the central grid or microgrids; such as distance from grid, economic feasibility and environmental sustainability.
• Analysis of design differences and requirements for microgrids, based on intended purpose and the needs of the end customer.

It has been determined that good planning, appropriate requirements and clear regulations for microgrids limit the risk of stranded assets and enable better business cases for the involved stakeholders.