Summer energy poverty is no longer a marginal issue. Across Europe, longer and more intense heat waves are exposing a gap in the way energy poverty has traditionally been understood and addressed.
For years, most policies and projects have focused primarily on winter: whether households can afford adequate heating and maintain a minimum indoor temperature. This remains essential. But it is no longer sufficient.
The experience of projects where Ecoserveis has participated such as CoolToRise show that summer energy poverty cannot be understood only through income, energy bills or meteorological data. It emerges from the interaction between heat exposure, housing quality, neighbourhood conditions, health, social circumstances and people’s real capacity to adapt .
The challenge now is to move from a narrow focus on heating affordability towards a broader, year-round understanding of thermal vulnerability.
Who is most vulnerable in practice?
Energy poverty is still often assessed using income as the main proxy for vulnerability. Income matters, but summer risk is much more spatially and physically determined. The real danger appears where four factors overlap: heat exposure, poor housing, health vulnerability and limited adaptive capacity.
In practice, some of the highest-risk groups include older people living alone, particularly those in top-floor apartments, poorly ventilated buildings or dense urban neighbourhoods.
People with chronic illnesses or disabilities may also face increased risk, especially when heat affects mobility, medication, sleep or the ability to carry out basic daily activities.
Low-income tenants are another particularly exposed group. They often cannot renovate the dwelling, install external shading, improve ventilation systems or replace inefficient appliances. Even where air conditioning is available, fear of high electricity bills may prevent them from using it.
Postal code can also be a strong predictor of summer energy poverty. Neighbourhoods differ significantly in nature-based solutions, building density, access to public facilities, night-time temperatures and the concentration of vulnerable populations.
Looking beyond the household
Projects such as CoolToRise also showed that summer energy poverty cannot be solved solely through household-level advice or individual behaviour change. en
People can close shutters, ventilate at night, drink water or avoid using the oven. But these strategies have limited impact when the dwelling overheats structurally, the street remains hot throughout the night or windows cannot be opened because of noise, pollution or security concerns.
The building and the neighbourhood are therefore central units of analysis.
A poorly insulated top-floor flat in a dense urban area with little vegetation can remain dangerously hot long after outdoor temperatures fall. Conversely, a household with similar income living in a shaded, well-ventilated building may face much lower exposure.
Summer energy poverty is not simply a problem of individual consumption, but also of housing, urban design, public space and institutional capacity.
What policy evidence captures — and what it still misses
Since CoolToRise was implemented between September 2021 and August 2024, summer energy poverty has gained greater recognition at policy level. New research, policy discussions and initiatives increasingly acknowledge that access to adequate cooling is becoming a social and public health concern .
However, much of the available evidence still relies heavily on outdoor temperature data, income indicators and household surveys. These are useful, but they do not fully explain what happens inside homes or how people experience heat.
Two households with the same income and living in the same city may face radically different levels of risk. Exposure can vary according to whether the dwelling is on the ground floor or the top floor, its orientation and solar exposure, the quality of insulation and external shading, the possibility of ventilating safely at night, the density and morphology of the surrounding neighbourhood, the presence of trees, green areas and shaded public spaces or the efficiency and affordability of cooling appliances.
Current evidence also tends to underestimate what could be called the “culture of heat”: the habits, expectations, knowledge and social norms that influence how people respond to high indoor temperatures.
Thermal comfort is not experienced in the same way in winter and summer. People generally show greater physiological and behavioural adaptation to warm temperatures than to cold conditions. This means that a single fixed indoor temperature threshold cannot fully describe summer comfort or risk.
Governance matters as much as infrastructure
Summer energy poverty cuts across energy, housing, health, social services, climate adaptation and urban planning. Yet these areas are often managed separately.
Climate shelters and neighbourhood cooling measures work best when responsibilities are clearly distributed and local actors share information.
Municipalities may identify vulnerable neighbourhoods, health services may recognise high-risk individuals, social organisations may have trusted relationships with residents, and housing departments may understand the condition of the building stock. Without coordination, these pieces remain disconnected.
Governance should not be treated as a secondary aspect of technical intervention. It is often what determines whether measures reach the people who need them.
From seasonal responses to year-round protection
Addressing summer energy poverty requires more than adding cooling measures to policies originally designed for winter. It requires a shift in how thermal vulnerability is understood, measured and acted upon.
Projects and public authorities should assess whether homes remain safe and liveable throughout the year, considering not only household income and energy costs, but also indoor temperatures, building performance, health conditions, tenure, neighbourhood characteristics and access to public cooling infrastructure.
This also means ensuring that measures intended to reduce winter energy poverty do not inadvertently increase summer overheating. Renovation strategies should combine insulation with external shading, ventilation, passive cooling and protection against excessive solar gains.
The central recommendation is therefore clear: Europe must move from a narrow heating-affordability approach to a year-round thermal vulnerability framework.
Summer energy poverty is not simply winter energy poverty under hotter conditions. It has its own drivers, spatial patterns and inequalities. Effective responses must start from people’s lived experience, while acting simultaneously at household, building, neighbourhood and institutional levels.
Only by connecting these dimensions can Europe ensure that the transition towards more efficient and climate-resilient homes also protects those who are most exposed to heat.
