Passive House is set of standards for sustainable construction, and houses built to those standards have dramatically lower energy needs. It is most commonly applied to homes, as it requires an attention to detail that’s challenging at a larger scale. There are exceptions, and to that list we can now add Klinikum Frankfurt Höchst, the world’s first Passive House hospital.
Foundations for the new hospital were laid in 2016, and it is now being fitted out. Currently the largest construction site in Frankfurt, the six storey hospital will be complete in 2019. Several months of testing are scheduled before it opens, as any tweaks or patching up will be very disruptive once its in use. When it’s ready, operations and 2,000 employees will transfer from the existing 1960s build hospital nearby, with 36,000 patients and 80,000 out-patients expected every year.
The scale of the project is daunting enough, but there are other challenges that are specific to hospitals. One of them is hygiene. Passive Houses rely on high levels of insulation, triple-glazed windows, and sealed building ‘envelopes’. A key principle is to make the building air-tight, and then use mechanical ventilation that brings air in and captures the heat from outgoing air. This technique is more complicated when used in a hospital. Fresh air is important. Smells needs to be carried away, and nobody wants infections spreading through the ventilation systems.
Another difficulty is the energy intensive medical machinery. MRI scanners require huge amounts of energy, and there are cold stores, ranks of sterilising equipment, and much more besides. Keeping costs down on light and heat is one thing, but a lot of work has gone into sourcing energy efficient medical equipment wherever possible.
It’s a highly ambitious project, but there are very good reasons to apply Passive House standards to a hospital. They’re occupied and busy around the clock, every day of the year. That alone makes them big energy users. They need to be comfortably warm for patients, so heating bills are high. Then again, with thousands of people coming and going and lots of machines running, they can get too hot and stuffy in the summer and need to be cooled.
Those costs are often borne by the public sector, and in an age of shrinking budgets and rising healthcare costs, cutting energy bills could be significant. It’s more expensive to build this way, but the savings will pay for it in the long term. Germany has 2,100 hospitals, and many of them are due for refurbishment and modernisation. If the concept can be proved in Frankfurt, it may inspire a new generation of hospitals across the country.