Why does the electricity consumption of data centers worry?

MadridSpain has for some time been boasting about having managed to contain the price of the electricity bill compared to other surrounding countries in a context marked by strong tension and volatility in the global energy market. The main reason: the deployment of renewable energies, which lower the wholesale price of the pool electricity –reducing gas consumption, which is more expensive–. Nothing that could go in the opposite direction pleases the Spanish government, which now fears that the deployment of the data center industry driven by the rise of artificial intelligence (AI) is going, precisely, in that direction.

"Do you know how much data centers increase the electricity bill you pay? A lot", stated the Minister for Digital Transformation, Óscar López, in an interview on TVE this Monday morning. Pedro Sánchez's executive is negotiating with the sector a draft royal decree to regulate the requirements for energy, environmental, and resilience and digital sovereignty sustainability for data centers. The text initially proposed opened a clash with the sector, which rejects it and has threatened to withdraw investments. The minister himself has confirmed that talks are being held to make it "balanced".

One of the most contentious points is the requirement that data centers use new generation renewable energy every hour they are in operation, and at least 80% of their energy consumption. This, however, opens another debate: where these data centers are installed, far from or close to the energy source.

What consumption are we talking about?

Neither the Ministry for Ecological Transition, nor the Ministry for Digital Transformation, nor even the Spanish government's decree include calculations of what the increase in electricity costs in the country might be with the deployment of data centers: initially, it was estimated that they would account for a demand of between 2.5 and 3 GW by 2030, but this has already been exceeded in terms of "pre-conceived power," according to the minister. This refers to the forecast of admissible power that the electrical grid can support.

Although it is happening in dribs and drabs (it takes months to build the facilities), their growth in the country has not ceased, and in 2025 the power installed by data centers was 439 MWh. A Barclays report indicated that by 2025 they would represent between 14% and 24% of the electricity demand in the country.

The key to understanding the concern is that if the increase in this electricity demand is not accompanied by new inframarginal generation (renewable technologies such as wind or solar, which are more economical) and gas gains weight to satisfy consumption, the price of the pool could skyrocket for everyone.

Sources from the Ministry for the Ecological Transition insist that the concern is not linked to the capacity of the electrical grid, but to this increase in the wholesale price. This is also important because large electricity companies have reported that the current Spanish grid does not have enough capacity to handle the arrival of new industry that depends on electrification to meet its energy demand (this is the case with data centers). That is why they have asked to reinforce and improve this grid with more investment, which also impacts the electricity bill through elements such as access tolls.

What has happened in other countries?

In 2025, global electricity consumption by data centers reached 415 TWh (1.5% of global demand), according to data from the International Energy Agency (IEA). The same organization forecasts that it will double to 945 TWh by 2030. The United States and China account for nearly 80% of the projected growth. In fact, the minister gave the example that in the North American country, citizens' protests against their deployment have grown.

The same country that has established itself as a laboratory for this industry and everything surrounding it, starting with artificial intelligence, is beginning to have states where its installation has been questioned. This is the case in Maine, but also in New York.

But there is no need to go that far. In Ireland, the minister exemplified, 30% of electricity consumption is the result of data centers. Their rise and that of artificial intelligence have led to an increase in electricity consumption to the point that the country has opened the debate on the use of nuclear energy, which has been banned for years. The European Union is also flirting with doubts: the Executive Vice-President of the European Commission for a Clean Transition and former socialist minister, Teresa Ribera, has called for a global "reflection" on data centers to prevent "negative effects for society as a whole" and has used the "notable" increase in the electricity bill as an example.

Faced with this landscape, López has questioned whether the deployment of data centers should be done without taking into account, precisely, the consumers' electricity bill. "Should data centers be sustainable? Of course. Should they be built at the expense of us all paying more for the electricity bill? I don't think so," said López, who pointed out that there are other industries that "compete for energy" and that "create more jobs." At the same time, however, he acknowledged that more supercomputing capacity is needed. Spain, in fact, has proposed to have one of the first artificial intelligence (AI) gigafactories in Europe.