Data centres and the future: the energy challenge facing Italy

From the cloud to streaming platforms, and from e-commerce to artificial intelligence, the entire digital world that surrounds us today is held up by the unseen, unheard infrastructure of data centres: the real engines of the digital economy, hosting servers, archives, and applications, and consuming quantities of energy comparable to those of entire cities. According to the International Energy Agency (IEA), data centres around the world consumed around 460 TWh of electricity in 2022, representing almost 2% of global demand. Predictions indicate that this consumption could grow by around 30-40% by 2026, driven by the explosion in generative artificial intelligence and the expansion of hyperscale clouds.

In Europe, the proportion of electricity consumption attributable to data centres varies from 0.5% to 2.5% depending on the country, with significant concentrations in certain areas like Frankfurt, Amsterdam, London, and Milan. Italy is rapidly carving out a position for itself as a digital hub, with Lombardy at the centre of this development.

It's no wonder, then, that Terna’s Development Plan reveals the most significant growth in requests for the connection of new data centres to the National Transmission Grid (NTG) to come from Lombardy (and from the north of the country more generally). As of June 30, 2025, requests from data centres in Italy exceeded 300 projects, totaling more than 50 GW (compared to around 30 GW at the end of 2024), according to data from the national transmission system operator.

Why do data centres consume so much energy? A data centre is an energy-intensive ecosystem by definition. It requires electricity to power thousands of servers which are active 24/7, cooling systems which often consume almost as much as the hardware itself, and infrastructure for security, fire safety and operational continuity. The most critical element remains cooling; in fact, the British newspaper The Guardian has reported that data centres can consume millions of litres of water per year to cool the server rooms. What they really need, however, is not simply to receive energy, but to receive it in a stable and resilient form, as continuity is vital to prevent digital blackouts resulting in incalculable economic losses.

Terna’s strategic role in powering data centres. The question of energy supply continuity is key to the business of large companies like Terna, the national transmission grid operator, which is working specifically to ensure the efficient planning of grid infrastructure and the secure, stable and efficient functioning of the electricity system 24/7.

Terna manages over 75,000 km of power lines and 900 substations, and under its 2024–2028 Industrial Plan update, it has earmarked €16.6 billion to expand and strengthen the national grid. Of this sum, around 10.8 billion euros are earmarked for development projects to overcome any grid congestion and integrate renewable energy, issues which have a direct impact on enabling the use of sustainable energy to power data centres without load limitations. These interventions can take many forms.

• The construction of new substations which can be used to provide connection points close to the data centres, with adequate standards of reliability.
• The rationalisation and restructuring of the grid in key areas with interventions in the province of Turin, the metropolitan area of Genoa, Brianza, Brescia, Cremona and Milan, which will support high levels of data centre integration in an area of strategic importance due to its position between Italy, Switzerland, and the other European digital hubs.
• The construction of new links and interconnections with projects like the HVDC Milan-Montalto backbones, the Adriatic Backbone, the SA.CO.I.3 and the Tyrrhenian Link (West and East branch), all DC infrastructure which make it possible to transport large quantities of energy across long distances with little loss, ensuring data centres have access to renewable energy at low prices even when they are physically distant from the renewable production sites.
• The upgrading of the existing grid by strengthening infrastructure to make sure it is capable of bearing the growing loads. Hyperscale data centres can require 100-200 MW in DC power, equivalent to the consumption of entire urban districts, but there have also been connection requests in excess of 500 MW.

Environmental challenges and the energy future of data centres. Across the globe, data centres are coming under growing pressure to reduce their environmental impact. In addition to their electricity consumption, the massive quantities of water they use for cooling risks creating conflict with local communities in areas subject to water stress. A single data centre can consume up to 5 million litres of water per day, equivalent to the needs of a town with 30,000 inhabitants.

In Italy, there are two aspects to the challenge: on the one hand, guaranteeing stable and sustainable energy for data centres; and, on the other, ensuring service continuity for homes and traditional businesses. With this in mind, and as emphasised in the Development Plan, Terna has set itself the goal of reducing dependency on foreign energy (currently at 60%, with a target of 37% by 2030); doubling the installed capacity of renewables, from 50 GW in 2024 to 107 GW by 2030, a growth of +57 GW; and integrating 12.9 GWh of storage capacity by 2030, an essential factor in managing the intermittent nature of renewable sources and ensuring the continuity of supply.

The digital transition and the energy transition are parallel pathways travelling in the same direction. For this reason, Terna is also investing in the digitalisation of the grid with Digital Twin and advanced automation projects, with the goal of managing energy flows in real time in order to meet the ultra-reactive demands of data centres.

In any case, the growth of data centres in Italy and all over the world shows no sign of slowing down. Their existence is now essential for clouds, AI, e-commerce, digital health, and smart cities. But their intensive demand for energy creates systemic challenges that only Transmission System Operators like Terna can resolve. This makes electricity infrastructure the deciding factor in paving the way for a sustainable and resilient digital future: every time we open an app, ask Siri a question or make an online transaction, it's the national electricity grid which silently makes digital life possible for all.