The energy transition

  ⁽³⁾Senior Researcher, INESC TEC & Assistant Professor, Faculty of Engineering of the University of Porto

The decarbonisation of the economy (and of society) is an essential component to tackle climate change and its terrible consequences. Although the term “transition” suggests continuity, strong measures were taken or projected, throughout the world (namely in the European Union); first, by cleaning the electricity generation mix (more renewables, no coal, less natural gas) and second, by transferring the consumption in transportation, industry, and domestic uses, from fossil fuels to electricity. Efficiency is, of course, among the concerns in all the cases.

This is a simplistic description of the energy transition, since accomplishing these objectives requires new developments in many technical domains and will change the way our societies are organised. Addressing some of the relevant issues is the main idea behind this special theme, so we are not trying to describe systematically all the details, but rather present original thoughts on selected topics, as a contribution to the readers’ perspective of the subject - either because the topic is less obvious or because relevant questions, not always explicitly formulated, are answered.

We start with the 100% renewables goal for the electric system, something that is desirable and feared at the same time. Carlos Moreira and Rui Castro address this topic and share their view on the necessary changes to meet said goal and the overall consequences.

In the foreseeable future, the importance of distributed generation (namely Low Voltage solar photovoltaic production) will increase, as compared with the traditional centralised electric power system situation. The concept of security of supply and associated methodologies may need a reformulation because of the changes in the global flows of the electric system. Leonel Carvalho discusses the relevant aspects of present and future evaluation of the security of supply.

The Portuguese and the UE electricity markets operate according to a structure designed to accommodate conventional players (centralised generation companies, retail energy sellers) in a marginalist scheme, although feed-in tariffs (to remunerate the special regime production, i.e., CHP e renewables) were possible from the beginning. Should this organisation continue? João Saraiva analyses this question, while Jose Villar, Ana Antunes e Cláudio Monteiro discuss the active role of energy communities in the energy transition.

Still regarding how the overall electric system is organised, but this time in technical terms, we feature an outlook on the role of energy conversion systems based on advanced power electronics, and their relevance to the fast development of smart grids and microgrids, issued by João Afonso, Carlos Antunes, Clara Gouveia and Vítor Monteiro.

As pointed out before, the energy transition is more than to simply replace everything by electricity in this sense, we dedicate part of the material to specific energy related topics: buildings, industry, and mobility

It is widely acknowledged that buildings are responsible for a great share of global energy use; that’s the starting point of Vítor Leal, who highlights the role of buildings as a giant “battery” of the energy system.

As for industry, Zenaida Mourão and Luis Guardão review the challenges and opportunities associated with the energy transition, taking advantage of other shifts in progress to reach a more efficient industrial sector, with a strong and positive impact on sustainability.

Mobility is one of the main sources of discussion, theories, proposals, and controversy. We will contribute to the topic of sustainable mobility through a specific outlook that deserves more attention. Álvaro Costa presents an alternative to the underground mode for public mobility and discusses its advantages and limitations.

Of course, a key element of the energy transition is a dramatic increase of the production of electricity from renewable sources, even if we are collectively able to be much more efficient. The topic of offshore parks is addressed by Bernardo Silva from a multi-technology point of view, with a common harvesting and transmission structure.

Mobility is one of the main sources of discussion, theories, proposals, and controversy. We will contribute to the topic of sustainable mobility through a specific outlook that deserves more attention. Álvaro Costa presents an alternative to the underground mode for public mobility and discusses its advantages and limitations.

Answering one of the FAQ about the future of renewable energy sources, António Vallêra and Miguel Brito estimate the limits of solar PV generation, and its sufficiency to meet the electricity consumption, according to different electric mobility scenarios.

Storage has been discussed intensively - from the classic hydro storage and other forms of non-electric energy storage to mobile and stationary batteries -, but we opted to address the emergent topic of renewable gases and green hydrogen. Peças Lopes, Joel Soares and Bruno Santos contribute to the discussion of the advantages and difficulties of this approach, developing the idea of a hydrogen seasonal storage strategy.

Less than one year ago, we would stop here; but nowadays, it is important to convey the message that the recent events affecting Europe’s energy supply do not justify dismantling what we have already achieved regarding climate change. For instance, there is no sense in reverting the decommissioning of coal-fired power plants.

A final word to remember, within the same framework, all the issues associated with nuclear power - from safety and security concerns to the unsolved problem of disposal of radioactive waste.

About the infographic

The INESC TEC activities in the energy sector are mainly undertaken by CPES (Centre for Power and Energy Systems), but other centres explored their competencies in different areas (computer science, ICT, etc.) to participate in multidisciplinary projects related to energy. This includes support to prototype development and testing through laboratorial infrastructures such as SGEVL (Smart Grids and Electric Vehicles Laboratory) and others.

The impact on industry is a constant concern of INESC TEC in this sector, and long-term partnerships have been established with EFACEC, EDP, REN, EDA and EEM. New partners (including international partners), reflecting the changes in the energy sector, emerged meanwhile, namely Sonae (Elergone Energias and Capwatt), Mota-Engil Renewing, SAP, ENEIDA, Dourogás, ENTSO-E, APG, TNO, and RWTH, among others.

The infographic presents data for the period 2017-2021, mainly from CPES, but also including contracts developed by other centres.