The Green Grids Initiative’s first blog post made the case that there can be no transition without transmission. Grid infrastructure is the backbone of the power system, and as the share of renewable energy in power systems increases, the ability to transfer power from wherever it is generated to wherever it is nedeed will grow in importance.
Grids are complex and expensive systems to develop, but one category of grid infrastructure stands out for the particular challenges it faces: interconnectors.
An interconnector is any grid infrastructure that connects two or more power systems operating under different legislative, regulatory and/or system operation regimes. Generally speaking, interconnectors make up only a small portion of the total amount of grid infrastructure within a system operator’s purview. The European Union (EU), one of the most interconnected regions in the world, has set a target for cross-border interconnection of 15% by 2030, meaning that by this date, EU members should be able to transmit at least 15% of the electricity they produce across their borders.[1] For most other countries, the level of interconnection is smaller still.
Even a relatively limited amount of cross-border connectivity, however, can bring real benefits, allowing system operators to jointly take advantage of larger and more diverse power systems than any one country or jurisdiction could develop on its own. Interconnected systems are able to more effectively and efficiently react to changes in supply, which in a high-renewables world becomes increasingly weather dependent and therefore harder to predict. Interconnectors can help manage peak demand through the sharing of surplus supply and reserves and they can also give developers access to regions with high and growing demand, increasing the economic case for developing new generation. Interconnectors can therefore enable the more cost-effective and secure integration of higher shares of renewable energy and other low-carbon resources.
In many parts of the world, however, progress on interconnector projects is slow or entirely stalled. This is not because of an absence of interest or ambition. In Southeast Asia, for example, the third ASEAN Interconnection Masterplan Studies (AIMS III) found that between 26,644 MW and 30,114 MW of new interconnections would be economically and technical viable, but as of 2020, only 7,720 MW of interconnector capacity had been developed.[2] The primary obstacle to progress is the scale and complexity of the task itself. Developing any transmission project is challenging, requiring among other things the development of feasibility studies, stakeholder engagement process, and regulatory compliance. Interconnectors have the additional complicating factor of involving more than one jurisdiction. This means coordination of planning, alignment with and integration into existing regulatory regimes, and agreements on cost sharing and cost recovery, as well as many other complicating factors.
Governments facing this array of complicating factors may reasonably choose to focus instead on domestic grid development, where these factors are easier to manage. But doing so to the exclusion of interconnector development means power systems must manage entirely with domestic resources, which can in turn make the energy transition more challenging and more expensive in the long-run.
What would be helpful is a guide for governments to help them effectively develop and leverage interconnectors – something that reduces the complexity and helps overcome obstacles to progress.
With that idea in mind, the GGI has developed a set of Principles for Interconnectors. Aimed primarily at relevant government agencies, the Principles aim to provide guidance to countries that are actively seeking to, or merely interested in, developing large-scale interconnector projects.
The principles themselves are built around the lifecycle of an interconnector, which can broadly be broken down into four stages:
1. Concept
2. Project development
3. Operation
4. Decommissioning
Each stage contains a number of steps or sub-stages, from preliminary feasibility studies at the earliest part of the concept stage, to agreement on cost-sharing and financing modalities at the development stage, to implementing effective operating protocols after the project has been fully commissioned, and finally, ultimately, safely decommissioning the transmission infrastructure at the end of its life. Taken as a whole, the Principles aim to be useful for projects regardless of where they are in their lifecycle, whether it be just a line drawn on a map, or an existing transmission line whose use must be reconsidered in the context of a rapidly evolving power system.
The Principles for Interconnectors have been developed by a task force formed under the GGI Asia-pacific Working Group but are based on input received from experts from the GGI Ecosystem and beyond with universal principles in mind, so that the principles could be applied in many regional contexts. Each principle contains case studies and, where relevant, references tools that may be useful to support their implementation. Ultimately, however, the Principles are a living document. They will continue to evolve and grow over time, based on target country and outside expert feedback, and on their real-world application.
Written by Matthew David Wittenstein, Chief of Section for Energy Connectivity, United Nations Economic and Social Commission for Asia and the Pacific