Cities are changing. And energy must keep up.

Portuguese cities will change more in the next decade than they did in the previous two. This transformation is not only inevitable; it is already visible. And there is a central element that connects all the pieces of this process: energy. If we want to talk about mobility, housing, sustainability, or digitalization, we must first talk about energy. A clean, digital, and smart energy system can leverage more affordable housing, efficient mobility, and a more competitive industry. What is at stake is not a distant future. It is, already today, quality of life, social cohesion, and economic attractiveness.

Energy plays a structuring role as a fundamental pillar and innovation platform. When well integrated, it becomes an invisible mesh that connects buildings, mobility, and grids, ensuring that the right kWh reaches the right place at the right time. Clean electrification, combined with energy flexibility, can reduce imports, stabilize tariffs, and smooth consumption peaks. But this requires planning, regulatory clarity, and a vision of a city where urbanism and energy speak the same language.

Portugal is already proving it's possible: in 2024, renewable sources covered 71% of national electricity consumption, the highest level ever, reducing CO₂ emissions from 3.7 Mt to 1.9 Mt. We're also seeing progress in self-consumption, electric mobility, and grid digitalization. However, bottlenecks persist: slow licensing processes, limited capacity in dense areas, and a disconnect between urban and energy planning.

Integrating clean energy into cities isn't just a matter of technology. Saturated grids require reinforcements and active load management. In historic centers, there's also the dilemma of infrastructure preservation and aesthetics. Initial costs drive away families, condominiums, and SMEs, while there's still a shortage of skilled labor for installation and maintenance. Furthermore, the lack of timely consumption and production data limits management effectiveness.

But it's not just about overcoming technical barriers. The transition must be fair and inclusive. Rehabilitation programs in social housing, dynamic pricing that protects vulnerable families, and accessible green public transportation are essential. Sustainable cities without social justice ultimately generate new inequalities.

Looking abroad, some European cities offer interesting insights: heating and cooling networks in Copenhagen or Stockholm, Barcelona's "superblocks" that reduce traffic, or the energy community models in Amsterdam. In Portugal, despite inspiring projects like InovGrid in Évora—which automated grids and reduced consumption—; in Lisbon—with the "Smart Lisbon" project that is consolidating an integrated urban management platform that aggregates energy, environmental, and mobility data; or in Porto—where the municipality invested in photovoltaics in municipal buildings with a clear replication strategy and reduced greenhouse gas emissions by 52.2% between 2004 and 2020—we need to scale these experiences, replicate them quickly, and ensure government stability.

Mobility is perhaps the most immediate reflection of this transition. Electric vehicles already represent almost 20% of passenger vehicle sales and can function as an energy resource through smart charging and bidirectional (V2G/V2B) capabilities. Micromobility requires adequate infrastructure and tariff integration. Multimodal hubs, equipped with solar panels, storage, and dynamic load management, can become true energy assets.

If we fail to integrate, the cost will be high. Cities with expensive and volatile energy, overloaded grids, and unreliable services will lose competitiveness and quality of life. Pollution will increase, multiplying heat islands, and the transition will benefit only those who can afford it, exacerbating inequalities.

On the other hand, if we harness this shift effectively, cities can strengthen their resilience and become more accessible, inclusive, and sustainable spaces. The decentralization of production through energy and self-consumption communities already demonstrates how citizens can also become producers, reducing costs, increasing independence, and generating community cohesion.

We're at a point where it's not enough to simply announce targets. We need to accelerate implementation, simplify processes, and ensure that every urban planning decision takes the energy dimension into account. Because, ultimately, cities and energy are two sides of the same coin. Cities are changing. The question is whether energy will be able to keep pace.