Switzerland's hospital heat bill: the diagnosis is in

A new University of Zürich study puts a CHF price tag on what heat already costs Swiss hospitals, and shows the bill rising in every scenario. The missing piece is an investment case that turns that evidence into funded action.

• A new peer-reviewed study by the University of Zürich puts a CHF price tag on heat's toll on Swiss hospitals CHF 20.6M annually today, rising to CHF 52M by the 2060s  and the projection is unambiguous: costs escalate under every emissions scenario, driven by aging demographics and rising temperatures.

• The conclusion is clear:  Adaptation investment is needed regardless of the emissions path and  yet a persistent data-to-action gap, not a lack of evidence, is what holds back investment at the scale required.

• The same analytical approach that quantifies the cost of inaction points to what is missing: extend the logic to the cost of action, compute the ROI, and you have the decision tool that converts climate risk into investment decisions and that is precisely what Resilens provides.

We knew heat kills. Now we know what it costs. Will we wait another 20 years to act?

In the summer of 2003, a heatwave killed an estimated 70,000 people across Europe, among them around 1,400 in Switzerland alone. The event was treated as a wake-up call. Two decades later, in 2022, Switzerland still recorded 474 heat-related fatalities (and these numbers are only set to rise in 2026). The warning was heard. The adaptation did not follow at the scale required.

Switzerland is living that lesson right now: June 2026 broke national temperature records, MeteoSwiss raised heatwave danger to level 4, and a second heat wave is forecast to hit Central Europe in early July. The costs in this piece aren't a future projection. They're this week's forecast.

Awareness has grown since then, and the research has kept pace. The study Quantifying the financial burden of heat-related hospital admissions in Switzerland under a changing climate: A scalable analytical framework by Vaghefi et al. (2026) goes one step further than documenting harm: they put a CHF price tag on inaction. That is progress. A price tag creates an investment incentive, but it does not yet create an investment case. And it is an investment case that decision-makers need to justify concrete, site-specific adaptation spending: not just evidence that heat is costly, but a defensible answer to the question every budget holder eventually asks:  “What does this intervention cost and what is the return on investment?”

The price tag on inaction

What makes the Vaghefi et al. study significant is not only the numbers, it is how they were produced. The researchers built a modular, five-component analytical framework: climate data, exposure definition, epidemiological modelling, cost estimation, and future projections. In a nut shell:  The framework converts raw temperature records into CHF figures.

The results are striking across all three emissions scenarios modelled. Under the moderate path broadly consistent with current climate policy, additional annual heat costs grow from roughly CHF 8 million in the 2030s to CHF 30 million by the 2060s. Under the high-emissions scenario, heat-attributable costs reach CHF 52 million per year, five times the additional costs projected for 2030. But the most important finding is this: even under strong mitigation, costs for the 75+ age group still rise by approximately 250%. The primary driver is demographic. Switzerland is aging, and older adults are the most heat-vulnerable population by a wide margin. Climate change adds a further 15–30% on top of that demographic baseline.

As Prof. Dr. Markus Leippold, one of the study's senior authors, puts it plainly: "The implication is blunt: adaptation is needed regardless of the emissions path."

The data-to-action gap

Vaghefi et al. quantify the cost of inaction, but the adaptation sector has a persistent problem that evidence alone cannot fix:  the data-to-action gap.

The successful implementation of adaptation relies on organisations understanding the hazards they face, knowing which measures to prioritise, and unlocking investment to finance them. Yet data and information consistently stop at the monetisation of climate impact. Practitioners lack the capacity to quantify the adaptation benefits, so adaptation lags behind rising climate impacts. And so the narrative that adaptation is an unprofitable enterprise goes unchallenged, while climate risk increases and the adaptation gap becomes ever larger.

The hesitation is understandable. Why should a hospital operator, a municipal planner, or an impact investor authorise complex, multi-year adaptation projects without knowing whether implementation costs would outweigh the losses avoided? A price tag on inaction answers half of that question. It does not answer the other half.

The consequences are visible at scale. The EU requires €70 billion per year in adaptation investment until 2050; currently only €20–33 billion is deployed. The gap is not a shortage of evidence, it is a shortage of investment cases that unlock financing and make adaptation happen.

The missing step: from cost of inaction to ROI of action

Without the modelling of adaptation benefit, you have a price tag on inaction. With it, an investment case. This is exactly where the Vaghefi et al. study points, not just to what has been measured, but to what needs to be built next.

As published, the framework's logic runs in one direction: From climate exposure to cost of harm. The missing step is to run the same logic in reverse. If we can quantify what heat costs a hospital system under a given emissions and demographic scenario, we can also quantify what a specific adaptation measure would avoid. The ratio of avoided cost to implementation cost is an ROI what Resilens calls the AdaptationReturn. And the AdaptationReturn is what converts evidence into a capital decision.

What is needed is a sixth component in the framework, an adaptation benefit module. That extension is not trivial.  This requires expanding from a hazard model to a measure catalogue, passive cooling, building insulation, shading, heat action protocols, each with its own cost, implementation timeline, and most importantly its avoided-harm estimate. It requires site-level granularity: which building, which population, which intervention. And it requires the output to land in a format that fits within the existing workflows of the people who need to act on it: Something a senior stakeholder can read, a funder can audit, and a financing instrument can be structured around.

That is the operational layer which adaptation is missing. And it is what Resilens is built to provide.

Resilens: from cost of inaction to business case for action

The Resilens decision engine builds on literature such as Vaghefi et al. and extends it one step further: from the cost of inaction to a site-level, measure-specific, finance-ready investment case. It combines climate hazard data with site-level exposure profiles and a catalogue of adaptation measures. For each measure, it estimates the harm avoided and computes a benefit-cost ratio that a decision-maker can act on directly.

The result is not a research output. It is a decision input, designed to sit inside the workflows that hospital operators, municipal planners, and adaptation practitioners already use, and to produce the defensible, comparable, auditable metrics that they need to justify adaptation investment.

Where the Vaghefi et al. study asks what is the cost of heat to Swiss hospitals under different futures, Resilens asks the follow-on question: Which specific facility is most at risk, what measure to prioritize, at what cost,  and what the ROI is in a way that an investor can price, a regulator can audit, and a municipality can act on.

The evidence base is in place. The data-to-action gap is the next problem to solve. If you're allocating capital or prioritizing adaptation spend for a hospital system or municipality, get in touch to see how the AdaptationReturn framework applies to your portfolio.