Is it possible to retire all coal-fired power plants by 2025? It is part of the doubts that ACERA A.G proposed to answer in the study requested from SPEC in collaboration with the Complex Engineering Systems Institute and the Federico Santa María Technical University.
The report takes on special importance in a global context in which climate change is a latent problem and does not threaten to become a reality, but we already live with it. Both the energy and transport sectors represent between 75% – 80% of greenhouse gas and particulate matter emissions, so considering the conclusions presented in this study becomes of a necessary urgency.

In this regard, Rodrigo Moreno, ISCI researcher and academic at the University of Chile commented: "The study shows what are the enabling conditions for a safe retirement of coal-fired power plants. Along the same lines, the study highlights the urgent need to promote investments in new technologies, such as energy storage, in order to give "firmness" to the capacity of variable renewable energies and thus be able to replace conventional thermal technologies reliably."

While Carlos Suazo, executive director of SPEC adds that "the development of the study allowed us to understand that it is feasible to find a technological mix of replacement of coal units, without compromising the security or quality of electricity supply. However, there are different topics of great relevance to discuss: what are the costs involved, what is the technological deployment to allow that energy transition, what technologies are needed for this to happen efficiently, what is required at the level of research and development at the local level to carry out this paradigm shift, among others. This analysis led to the search for solutions to modernize operating policies and the conceptualization of our market design. This last point is of utmost importance in order to allow a timely and efficient energy transition for citizens." Part of the conclusions are:

Despite the large number of projects under construction and development that will be integrated into the SEN in the coming years, an additional effort is required to remove the coal and adapt the system. There is a need for greater and timely developments in generation and storage capacity.

Additional infrastructure will be required to provide dynamic support to the system in order to maintain security and continuity of supply. Conversion of existing infrastructure and some operating policies reduces these requirements.

It is necessary to review various policies: gas availability and flexible intraday operation, diesel supply chain or definition of minimum stock, restrictions on hydropeaking, disincentives due to high levels of dumping, operation out of economic order and lack of remuneration for services such as inertia or cycling.

It is feasible to find a technological mix for the replacement of coal-fired units, even in scenarios of accelerated retirement to 2026.

This mix, accompanied by some operational practices, allows us to achieve two relevant aspects:
• Economic efficiency: supplying demand at minimum cost (adapting the system)
• Technical feasibility: maintain the robustness of the SEN in the face of imbalances that may jeopardize its stability and continuity of supply.

While infrastructure development is challenging and comes at a high cost, this is not identified as the main barrier to early retirement. The main barrier identified is related to the sufficiency of market signals and the current institutionality to attract such investments and facilitate the implementation of the necessary policies. This is because additional expansions to 2026 are mainly in the hands of the private sector. There would be no centralized processes such as tenders to regulated customers that add new capacity to that date.

It is worth asking, for example, whether market signals are sufficient for the integration of enabling technologies of incipient development such as storage and contribution of renewables to frequency control, among others.

Another relevant barrier is that investment decisions are not integrated into a single agent. Mismatches between the entry of new projects and withdrawals of coal-fired power plants are possible. Any failure in this process and failure to achieve a system adapted to the new scenario can mean a more fragile, less efficient and more polluting system.