What is Leiden University doing to make its buildings future-proof and independent of fossil energy?
Leiden University aims to greatly reduce CO2 emissions and energy consumption, and to achieve fossil-free construction and renovation. This means we need to use space and energy even more efficiently, and transition from green energy to more self-generated electricity. Given that raw materials are finite and the cost of building materials is constantly rising, our goal is circular renovation and management of our buildings. Making our campuses greener improves our environment, maintains our productivity and also helps to save energy.
The University’s Long-term Property Vision 2016-2025 (in Dutch)sets out how the University will develop from single complexes to three campuses with a specified spatial norm.
Our real estate strategy is described in detail in the Multi-year Investment Plan (MIP), which is updated annually on the basis of the latest insights. The current investment plan looks ahead to 2030.
The new working-from-home policy and steeply rising energy prices make it essential to use rooms much more efficiently. This topic is discussed each year by the Real Estate directorate and the faculties.
The Roadmap to carbon-neutral campuses shows how Leiden University aims to ensure that our buildings comply with the Paris Climate Agreement.
The main focus is energy transition: from fossil to non-fossil energy sources. Our aim is to have reduced CO2 emissions by 65% in 2030 and by 95% in 2050. We will achieve this by making our buildings more sustainable, bringing our natural gas consumption down to zero, drastically reducing other energy use and generating electricity ourselves as far as possible.
Three current developments make achieving these goals even more urgent:
- the energy crisis and the resulting large price increases
- the war in Ukraine, bringing forward the Netherlands’ intention to become independent of Russian gas
- warnings in the IPPC reports that the earth is warming even faster than predicted
Increasing the sustainability of our buildings makes the biggest contribution to achieving these goals. A particularly essential element is insulation when carrying out major renovations and new construction. This is a complex challenge in the case of protected historic buildings, where more regulations come into play.
[See the Roadmap tile in the right-hand column for a visualisation of the plans up to 2030.]
Buildings that use less than 70 kWh per square metre of usable floor area per year are known as future proof, or ‘Paris Proof’. At present, this standard is only met by the Arsenaal and a few parking garages. Five more buildings will become compliant around 2030, using thermal energy storage instead of natural gas:
- Lecture Hall Buildings
- South Cluster
- North Cluster
- New Lipsius Building
When district heating becomes completely fossil free, at least four more buildings will be Paris Proof:
- Van Steenis
Where are the solar panels located?
This interactive page of the online Energy Transition Monitor (in Dutch) shows how many solar panels there are on the roof of each of our buildings, and how much energy they yield.
There are several different quality standards and labels that indicate how future proof and sustainable a building is.
Leiden University uses energy labels to show the energy performance of buildings. These labels run from G (very inefficient) to A++++ (energy supplying). A disadvantage of this system is that the labels relate only to offices and teaching rooms, and not to laboratories. Nevertheless, the energy performance of our buildings will still improve if we aim for energy label A when carrying out renovations. The Energy Transition Monitor (in Dutch) shows the energy label that applies for each building.
BREAAM-NL quality standard
Leiden University works with the BREEAM-NL quality standard when making buildings more sustainable (new construction, major renovations and demolition). The performance level is determined on the basis of scores in nine categories, ranging from energy, water and material use to waste production and transport movements.
Leiden University’s minimum requirement for performance level is Very Good (3 out of 5 stars) and our ambition is Excellent (4 out of 5 stars). This is an internationally recognised way to show the extent to which a building is more sustainable, healthy and future proof, over and above the compulsory standards laid down in the Buildings Regulation.
WELL Building Standard
The Faculty of Humanities also takes account of the WELL Building Standard in developing the Humanities Campus. This quality standard emphasises the health of buildings and the wellbeing of their users. There are three levels of WELL performance: silver, gold and platinum. The WELL categories of air, comfort and light are also integral to the BREEAM standard. In addition, however, the WELL standard assesses both building-related health aspects, such as construction materials, building services and interior design, and human wellbeing resources, such as fitness and mind.
We are conducting a pilot with the WELL Building Standard (excluding certification) in the North Cluster renovation (Matthias de Vrieshof).
Goals for 2025 in terms of labels and quality standards
North Cluster; pilot
29% GFA has energy label B or higher (7 buildings)
40% GFA has energy label B or higher (14 buildings)
Construction, demolition and industrial waste comprise Europe’s largest and fastest growing waste stream, accounting for 30% of all waste. This is despite the fact that raw materials for construction are becoming increasingly scarce and their extraction damages the environment. We will therefore be taking a more circular approach to harvesting and construction: not merely demolishing buildings, but carefully dismantling them, so that materials can be re-used in new construction or renovation.
We already re-use all the wood from the renovation of University buildings: either in the same building or elsewhere on the campuses. We also try to find a new purpose for cable ducts, cables, windows, steel and other elements, either internally or externally. To enable re-use of materials, it is important to use demountable elements in construction, which can easily be disassembled in the same way as Lego. In other words, without glue or nails. At Leiden University we are developing our own standard, based on experience in practice.
- Sustainable demolition of the Gorlaeus Highrise (2017) with maximum re-use of materials (more than 90%). 150 tons of steel were used in the load-bearing structure of BioPartner. Read: The promise of re-use in the building industry (in Dutch). The first three storeys were kept intact for use as the future Gorlaeus bicycle storage (2024).
- The car park in Nieuw-Rhijngeest Zuid is made of second-hand paving stones.
See also the Circularity Circularity page on the Leiden Bio Science Park website.
- 2,900 metres of re-used wood was installed in the Arsenaal (in Dutch) geplaatst and the original windows (in Dutch) found a new use in the Circular Pavilion in Hoofddorp.
- 165,000 kg of construction, demolition and industrial waste was upcycled (91 kg of building waste per m2 of exterior wall) into WasteBasebricks by the company StoneCycle. These were used for the exterior walls of the Equipment Centre (Installatiepaviljoen, next to the Snellius Building). Even the CO2 emissions from manufacturing these hand-made bricks were compensated.
The new generations who will come to study or work at Leiden University in the future want a pleasant environment in the buildings and on the campuses. Working closely with an ecologist, we examine whether the following aspects can be achieved in every construction project.
Greening, cooling, climate adaptation and biodiversity
All our campus grounds should be ‘green-blue’, which means that at least 30% consists of vegetation and water elements. The vegetation can be either horizontal or vertical, growing along exterior walls, for example. We are aiming for this because it is important that everyone can sit in green surroundings within 500 metres of their workspace or study space.
Green spaces can process and hold back rainwater more effectively
Rainwater dilutes our brackish groundwater and there is less risk of flooding in the event of heavy rain.
It is already a legal requirement that renovations and new buildings must be climate adaptive; in other words, rainwater must be held back and allowed to drain slowly into ponds and ditches in the surrounding area (and no longer into the rainwater sewer). We also intend to improve this aspect in existing buildings and concreted areas.
On the Leiden Bio Science Park around the Gorlaeus Building and Nieuw-Rhijngeest Zuid, our aim is to achieve not only a tree balance (cut down 1 tree = plant 1 tree) but also a water balance for rainwater collection.
Greenery provides cooling
Climate change is resulting in more frequent heat waves. In an area composed mainly of asphalt and concrete, the temperature rises quickly and falls more slowly, because these materials hold the heat for a long time. This leads to heat stress in people and animals. Adding greenery helps to keep an area cool. The constant evaporation of water means that trees, grass and shrubs can lower the ambient temperature by as much as 7° C, which has a positive impact on people’s productivity and ability to concentrate.
Heat stress in visuals
See the mind map (in Dutch) produced by Amsterdam University of Applied Sciences, showing the impact of extreme heat in a concreted area. Or go to the National Heat Stress Map (in Dutch) and zoom in on Leiden or The Hague to discover the hot spots in terms of ‘feels like’ temperature.
Other advantages of green spaces
- Greenery reduces stress, which is beneficial for health and wellbeing.
- Green spaces and parks are good for social cohesion in the neighbourhood, as they provide places for people to meet.
- Greenery absorbs traffic noise and improves air quality by filtering out fine particulates and converting CO2 into oxygen
- Greenery increases biodiversity and creates a better habitat for birds and insects.
Emission-free construction logistics
Together with the Municipality of Leiden, the Province of South Holland and the companies Constructif, Renewi, CityBarge, Circle Logistics and other partners, Leiden University is working on emission-free transport of goods and industrial waste on Leiden’s canals. The Humanities Campus renovations will turn Leiden’s city centre into a building site for the next few years. We therefore aim to gain experience with emission-free transport by water while constructing the South Cluster, increasing the likelihood of this approach to construction logistics proving successful. Leiden University is thus following the national route towards Zero Emission Urban Logistics (ZES) (in Dutch), in which the Municipality of Leiden is also a participant. This concept will ensure optimal construction-related logistics, resulting in better accessibility in the city and region and greater safety for cyclists and pedestrians.
Leiden University restores, modernises and builds for the users of its buildings in Leiden and The Hague. In this, sustainability and biodiversity play an important role.
Read about the most eye-catching building projects.