La transizione energetica

Energy transition,
what is it and why is it so important?

Tips to avoid (or postpone) the end of the world

When it comes to reducing emissions and safeguarding the environment, as the operator of the Italian energy transmission grid Terna has an important responsibility towards society and its future.

Currently, fossil fuels still account for over 80% of global energy consumption; a change of course is essential to reduce our dependency on this type of energy and limit the global temperature increase.

Billion tonnes of CO₂ was emitted into the atmosphere

The transition under way will radically change the appearance of the electricity system. By focusing on projects and investments in network infrastructures, Terna is laying the foundations to optimise and support the current transformation process for an appropriate, safe and efficient system with an increasing focus on renewable energy sources.

For a leading transmission and dispatching operator, this commitment is formalised through investments in skills, technology and innovation to optimise the management of grid development and maintenance activities (Transmission Operator) and to ensure the safe and quality planning and management of the electricity service (System Operator).

Thanks to the unique expertise of its employees and its constant dialogue with the territories, Terna is able to contribute to the growth and development of sustainable projects in Italy.

The apocalypse we brought upon ourselves

The scientific community is united in its opinion that climate change is closely linked to human activity. The average temperature of the Earth has risen by approximately 1°C since the end of the nineteenth century, predominantly as a result of emissions of carbon dioxide and other greenhouse gases.

However, the most consistent rise in temperature has taken place in the last fifty years, with a trend of around +0.2°C every decade.

U.S. National Academy of Sciences

The scientific understanding of climate change is now sufficiently clear to justify taking steps to reduce the amount of greenhouse gases in the atmosphere

Intergovernmental Panel on Climate Change

Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia

International academies: Joint statement

Climate change is real. There will always be uncertainty in understanding a system as complex as the world’s climate. However there is now strong evidence that significant global warming is occurring

The leading cause of global warming has been identified by the scientific community as the greenhouse effect, which occurs when certain types of gases, such as carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄), prevent heat from leaving the atmosphere. These elements are joined by so-called “chlorofluorocarbons”, or CFC gases, artificial substances used in various industrial processes and responsible for the now infamous “hole in the ozone layer”.

In the last century, the use of fossil fuels such as coal and petrol, has drastically increased the concentration of CO₂ in the atmosphere.

The consequences of this phenomenon are already being felt: between 1993 and 2016 Greenland lost approximately 281 billion tonnes of ice per year, while Antarctica lost around 119 billion.

Among other things, as temperatures rise, it will become increasingly difficult to grow grains, the main source of nourishment for billions of people in many parts of the globe

Sea levels have also risen, increasing by approximately 20 centimetres in the last century. Similarly, the acidity of the oceans has increased by 30 percent since the onset of the industrial revolution, resulting in serious consequences for marine and plant life.

Above all, climate change is causing substantial changes in precipitation, with significantly higher rainfall in certain parts of the world and dangerous reductions in others. Droughts and heatwaves will increase both in frequency and intensity, with particularly serious repercussions for agriculture.

In light of global warming and the risks it poses for the immediate future, to prevent temperatures from rising excessively (over the 2°C defined by the Paris Agreement) the global economy must aim to cut its carbon intensity¹ by 6.4% each year until 2100.

Projection of CO₂ emissions in the various possible scenarios
Unit: gigatonnes of CO₂ equivalent (GtCO₂e)
The graph illustrates the trend of global CO₂ emissions in different scenarios. Following current policies and the pledges made by the various governments, CO₂ emissions will not drop significantly, the only positive scenarios are those defined by the Paris Conference, which plan to limit the increase in the planet's temperature to 2° or 1.5° compared to pre-industrial levels.
Source: Climate Action Tracker Data
Current Policy Projections
Pledges and Targets
2° consistent
1.5° consistent

Reaching this target would require a scientifically impossible reduction in emissions (and therefore in performance) of current fossil fuel plants. In layman's terms, this would be the equivalent of a car in 2050 using one litre of fuel per 200 kilometres, compared to the 20 kilometres managed by today's vehicles. This means that, in order to meet these targets, we need to develop technology that burns fossil fuels in a way that increases its energy efficiency tenfold, which would break every law of thermodynamics. How can we solve this problem?

The only viable solution is to focus on radical energy transition, which enables us to achieve the ambitious goal of combating climate change: only by decommissioning non-renewable and highly polluting energy sources can we feasibly stabilise the already seriously high concentration of CO₂ in the atmosphere.

1 Carbon intensity is the amount of carbon emitted per unit of energy consumed. A low carbon intensity corresponds to a high energy efficiency.

Energy transition:
it restarts here

Energy transition is the transition from current sources of energy production, based mainly on the use of non-renewable sources, such as oil, gas and coal, to a more efficient, less polluting mix of renewable energy.

Over the course of history, we have already seen significant energy transitions. Think of the move from wood to coal consumption that took place during the Industrial Revolution or the introduction of nuclear energy. But due to the increase in demand for energy, today's renewable sources are not capable of replacing the 'old' energy production systems, but rather complement them.

Global primary energy consumption for source types
Unit: kilotonne of oil equivalent (Ktoe).
SOURCE: IEA World Energy Balances 2018.
Natural gas

Between 1990 and 2015, the percentage of renewable energies used on a global level remained almost unchanged, with an insignificant increase from 13% to 14%. The reason for this lies in the fact that several countries had only recently entered the industrial world, drastically increasing their energy demand, which was primarily met by the traditional, already widely available and more affordable, pollutant sources.

Until only a few decades ago, due to the lack of technologies capable of replacing non-renewable sources, it was hard to imagine a solution to this problem. However, it is now possible to produce energy from renewable sources and transport it to where it will be consumed, at increasingly competitive prices, thanks to the transport and distribution networks.

Share by type of energy source
Unit: percentage (%).
SOURCE: IEA World Energy Balances 2018
Natural gas

What are the international organisations saying?

In order to address the issue of emissions, numerous initiatives have been launched by international organisations: only joint action between different countries can lead to concrete results on a global level in terms of climate change. In Italy’s case, there are three main sources to consider.

1 The Paris climate change conference (COP21) saw 195 countries come together to adopt the first universal and legally binding global climate agreement. The governments that participated in the conference have numerous individual objectives, but the three main objectives are:


2 The European Union has made long-term commitments to reduce CO₂ emissions by at least 40% by 2030. In terms of the approval of the Clean Energy Package (Clean Energy for All Europeans) presented by the European Commission in 2018, the main aim remains to prioritise energy efficiency, combined with leadership in renewable energy and guaranteeing the secure provision of electricity


The long-term aim is outlined in the “2050 - A Clean Planet for All” strategy presented by the European Commission in November 2018. This strategy demonstrates how Europe can guide the process of reducing emissions through a series of policies and initiatives that involve industrial policies, academic research and active citizenship

3 The integrated National Energy and Climate Plan (NECP) represents the Italian national energy strategy for achieving the objectives of efficiency, reduction of CO₂ emissions and development of renewable energy based on the European indications


In terms of renewables, the plan aims to cover 30% of final consumption with renewable sources. The contribution of renewables to final consumption is shared across 55.4% of the electricity sector, with 33% in the thermal sector and 21.6% in incorporation in transport - for example, through the massive spread of electric cars which is expected to reach six million vehicles in 2030.

The reduction of primary energy consumption expected by the PNIEC

With the total phase-out of coal-fired power plants set for 2025, renewables are expected to increase—from their current share of 34.1%—thanks to technological developments and the upgrading of currently active plants, in particular photovoltaic and wind power plants. Energy efficiency solutions will therefore become fundamental to encouraging lower consumption.

In this context, electricity grids play an even more central and strategic role than ever before, with a progressive transformation of the constant energy flows from large production plants to consumption centres and infrastructures capable of dynamically managing and sorting energy flows, which vary over time and space due to the strong uncertainty of renewable sources.

A power line in the background of a photovoltaic solar panel system in Latina, Lazio (photo by Terna)

Why does every Euro invested in renewable energy have to be matched by more than an Euro invested in electricity grids and services?

As the International Energy Agency states, every Euro invested in renewable energy sources must be matched by more than one Euro invested in the development of infrastructure to transport the energy produced. It is no use installing wind turbines where the wind is strongest—in the open sea for example—if you do not have an electricity grid capable of transporting the energy produced to the most populated areas where it is needed most.

This last point has become fundamental for Terna in its role as 'enabler' of the energy transition towards production based on renewable energy. The Group's activities and mission almost completely correspond with some of the United Nations’ Sustainable Development Goals.

Affordable and clean energy

Ensure universal access to affordable, reliable and modern energy services and significantly increase the share of renewable energy by 2030

Industry, innovation and infrastructure

Build quality, reliable, sustainable and resilient infrastructure, including regional and cross-border infrastructure, to support economic development and human well-being

Climate action

Strengthen the resilience and ability to adapt to climate-related risks and natural disasters in all countries through the implementation of the Resilience Plan

Terna's main tools for achieving these objectives are:

  • Investments to develop the transmission grid (Development Plan) and ensure its resilience.
  • Investments in the security and resilience of the service (Security Plan and Resilience Plan).
  • Plant maintenance.
  • Innovation aimed at accompanying the transition to renewable sources and promoting energy efficiency. This is how the network operator tackles the challenges of the six main dimensions of the electricity system.
Terna's National Control Center has the task of ensuring the functioning of the electrical system, to guarantee continuity and quality of the service in conditions of maximum safety (photo by Terna)

In particular, Terna's commitment to promoting decarbonisation revolves around the investment of significant resources to facilitate the systemic development of renewables.

This means that the transmission grid operator is constantly adapting the infrastructures so that they can transport the energy produced by renewable sources, as well as grid planning and real-time management of the electricity system.

The Italian National Transmission Grid Development Plan, which contains the works the Group, foresees for the next ten years and the status of those started in earlier years

Electricity is in fact very hard to store and must therefore be consumed as it is produced, ensuring that consumption and production are instantaneously balanced to avoid issues in service continuity.

For example, in the evenings, the energy produced from solar panels decreases rapidly, yet it is specifically during the afternoon that the peak consumption for the entire day is concentrated. On the contrary, peak production of photovoltaic energy is concentrated during the central daytime hours and, in future energy scenarios, the need to accumulate this energy in excess of consumption will increase progressively. Moreover, the northern Italian regions require a greater amount of energy, while the majority of renewable energy plants are concentrated in the south due to the natural availability of sun and wind.

To lead Italy through the energy transition, while continuing to guarantee the quality and safety of the electricity supply, the following five factors must be considered at all times.

Alongside the development of the national electricity grid, Terna is working to increase the interconnection capacity with neighbouring countries to increase the integration of the Italian and European grids, therefore guaranteeing energy exchange and services (for example, allowing the use of pumping plants in the north of Italy to supply foreign services). This is the case with the Italy - France interconnection: 190 kilometres of underground power lines, crossing 25 municipalities in the province of Turin: a unique project in terms of engineering and technological solutions, thanks to the design and construction of the longest underground power line in the world, with a total capacity of 1,200 MW and a very low impact on the environment and the territory.

In general, Terna's investments in the energy transition focus on making the Italian electricity system more sustainable and efficient, as well as significantly reducing CO₂ emissions: a substantial contribution to the battle against climate change.

A Terna electric station in Latina, in the hamlet of Borgo Sabotino (photo by Terna)