Energy Management in Historical Buildings [Case Study – Hospital de la Santa Creu i Sant Pau]

When we talk about historical heritage and energy efficiency, many actions may cross your mind: you may think of renovation works, improving insulation, repairing cracking, changing supplies, lighting… Any of these actions are valid, together with regular monitoring of consumption to analyse whether the measures taken are truly effective or not.

In Europe, 35% of the building stock is more than 50 years old. Even if they are of a certain age, these buildings, of whatever type, are not considered historic. But of that 35%, a small percentage are buildings with decades or even centuries of history, and which deserve particular attention. In this article, we review some of the main features of energy efficiency projects in historical buildings. We also share the success story of the Art Nouveau Site of the Hospital de la Santa Creu i Sant Pau in Barcelona, a UNESCO World Heritage Site.

Energy Management in Historical Heritage

The conservation of historical buildings, built decades or even centuries ago, can sometimes conflict with energy efficiency from a 21st-century perspective. Whether it has been well maintained or not, an old building can fail due to the wear and tear of materials. Pipes that leak, windows that no longer close as well, beams or roofs that lose insulation… And of course, the energy bill rises rapidly.

However, it is also important to highlight that any older buildings and especially from the modernist period already include elements to be more efficient from a design point of view. The orientation of the pavilions, the construction materials, the size of the windows, the landscaped areas and trees between each building… Some of the key elements of today’s passive construction (passivhaus) were already in place two centuries ago and are part of the architectural heritage.

This is very good news for the manager of a 19th-century building, whether it is a private or a public institution. If the structures are good and the building is in a good state of conservation, it compensates for investment in energy efficiency and renovation.

This preserves the historical heritage and reduces energy consumption to ensure its long-term continuity.

Historic Heritage or Energy Efficiency, should we choose?

Despite the above, there may still be doubts about the effectiveness of renovating and modernising a historical building.

The energy efficiency of a particular historical building may be excused if its renovation is difficult and costly, or it may adversely affect its conservation, but if this is the case with every building of a certain age, it can be a problem. A gap opens up between inefficient historic and cultural buildings, and new, modern buildings with little architectural value but high efficiency.

Moreover, from an economic point of view, energy efficiency has not always been a priority in the renovation of historical buildings although there is a lot of room for improvement and savings potential. In addition,  mentalities are changing: between awareness for the planet, energy savings and high energy costs, energy efficiency is no longer seen as an extra but as a reality to be considered. 

In this context, and taking into account both heritage conservation and energy savings, there is no need to choose between one or the other. It is clear that an energy efficiency programme in a listed building will have to be carried out with greater care than in a conventional building, involving architects and conservation experts. It will be necessary to work in tandem to achieve the objectives, but it is possible.

Retrofitting and Energy Efficiency 

At the European level, several ERDF (European Regional Development Fund) funded programmes have addressed the issue of historic heritage and energy efficiency. They have studied the maintenance, rehabilitation and energy efficiency of historical buildings in order to issue recommendations to the European Commission.

The European cooperation programme VIOLET has addressed this issue and released recommendations to tackle the energy efficiency of historical buildings at the European level. The Smart Heritage Buildings now paused, focused on IoT technology and sensors for historic heritage maintenance. Do you still have questions about the binomial historical heritage and energy efficiency, especially when it comes to different locations? Read on to find out more about the success story of the Hospital Santa Creu i Sant Pau Private Foundation.

Energy Management at the Private Foundation Hospital de la Santa Creu I Sant Pau

The success story of the Hospital Santa Creu i Sant Pau Private Foundation is one of energy efficiency, but also of the maintenance, refurbishment and care of a listed building with a long history.

Inaugurated in 1930, the Hospital de la Santa Creu i Sant Pau is divided into different buildings in the Art Nouveau style with garden areas between them. Considered one of the largest modernist complexes in the world, it was declared a World Heritage Site by UNESCO in 1997. Of the total number of World Heritage Sites, some 400 are located in Europe, of which 47 are in Spain.

Context of the Historical Heritage and Energy Efficiency Project

Hospital Santa Creu i Sant Pau Private Foundation manages both the Art Nouveau complex where the old hospital was located and the new hospital, which is currently in operation. 

These buildings or pavilions housed all the hospital’s activities until 2009 when the hospital’s activities were transferred to a new building on the same site.

Once the hospital had ceased to be used for this purpose, the Foundation undertook a project to refurbish and restore the Art Nouveau Site. Since then, it has been used for activities as diverse as research, culture, events and training.

During the restoration, special emphasis was placed on sustainability and energy efficiency. Because of the architectural value of the modernist pavilions, restoration as a cultural heritage and modernisation to be more efficient were developed at the same time. This included aspects of insulation, supplies, meters and energy efficiency.

The Energy Challenge

With an annual consumption of 2,307,705 kWh at the start of the project in 2014, one of the key objectives for the Foundation was to identify unnecessary consumption, as well as to detect differences between buildings with similar activities and surface areas.

In addition, the manual management of its 140 electricity, gas and light meters was inefficient, requiring an enormous amount of time and resources. Although the number and location of these meters were adequate, the existence of different models and manufacturers also presented a challenge in terms of homogenising information and monitoring effectively…

Thus, the main objective of the energy efficiency project was the maximum optimisation of energy consumption in the buildings on the site.

The Dexma Platform, and in particular Dexma Analyse, became the main tool for managing, measuring and monitoring the 15 buildings that make up the Art Nouveau site. They have also been of great help in facilitating the use of graphs, analysis tools and comparison of readings.

Do you want to know how and with what results? Download the case study to find out the details: ⬇️