The supermarket of the future
A supermarket designed as a net-zero construction that produces its own food for the region. This is the concept behind Rewe Green Farming and its prototype in Wiesbaden, Germany. Timber engineering is central to the company’s plan for similar stores.
The green space in front of the entrance is a haven for pollinators. Customers park their EVs on the permeable surface for charging with 100% green electricity. In the meantime, they can browse the shelves of regional goods – some of which have been produced on-site at the supermarket. On the roof, basil is growing in a greenhouse. Irrigation and natural fertilizer are provided by the fish in the store’s resource-friendly aquaponics farm. And the fish are sold just a stone’s throw away in the refrigerated section downstairs. Or they are taken to the region’s supermarkets. This saves time, uses environmentally friendly packaging and avoids long transport routes.
An increasing number of people are joining forces in food cooperatives that enable them to choose their own regional producers. Instead of shopping at major supermarkets, they prefer to set up their own supply chains. This change in the way people source their food is gradually causing large companies to rethink their approach. The pilot project Rewe Green Farming in Wiesbaden-Erbenheim, Germany, is the first supermarket in Europe with its own rooftop farm. Named “Store of the Year 2022” by the German Retail Association, it was also chosen as a UK Civic Trust Award Winner in 2024.
Sustainable design using timber
This is a new concept for the supermarket multinational, which chose a sustainable design that uses timber. 42 sculptured wooden columns bear the weight of the supermarket and its rooftop farm. They add a rhythmic structure to the hall and exploit a simple construction principle. Wooden beams of different lengths placed crosswise and lengthwise form a spatial structure that creates archways between the columns. A central atrium allows plenty of daylight in the supermarket.
We believe this is the future of climate-friendly construction. The timber columns lend a human dimension to the project.
Friedrich Ludewig, architect and founder of AMCE
The coniferous wood used for construction has been taken from domestic forests, says Rewe. According to a project brochure, the timber structure has been built with 1,100 cubic metres of this renewable raw material, which stores 700 tonnes of CO₂ over the long term. “We believe this is the future of climate-friendly construction,” says Friedrich Ludewig, architect and founder of the London office AMCE, which was responsible for the prototype design and planning. “The timber columns lend a human dimension to the project.”
Simple and modular
The visible timber construction creates a natural atmosphere reminiscent of traditional marketplaces. Owing to the high level of prefabrication for the timber columns and building stages, it took just eight weeks to assemble the entire structure. The modular construction system developed by the architects focuses on simplicity and ease of reproduction: “The structure is designed to be easy to build and simple to adapt. Rather than several elements that use advanced technology, we have instead chosen a large number of standard elements that are available locally and can be assembled with simple screw connections.”
This simple modular design allows the system to be adapted and configured for any store size. The advantages of timber construction are obvious, above and beyond its sustainability. Explaining the choice of material, Ludewig says: “In future, nobody will ask ‘why did you choose wood?’, but rather ‘why didn’t you use wood for that building?’.”
20,000 tilapia fish per year
Outside the supermarket, the planners came up with a different idea for the parking area to avoid the customary soil sealing. Instead of a conventional layout in rows, cars are parked in a ring of spaces that provides the same capacity. The surface is permeable, and the resultant green space is pollinator-friendly and nature-inclusive.
In future, nobody will ask ‘why did you choose wood?’, but rather ‘why didn’t you use wood for that building?’
Friedrich Ludewig, architect and founder of AMCE
It is a concept that “reduces soil sealing and creates permeable surfaces”, as Rewe explains. Rainwater is collected in cisterns and subsequently used for cleaning, sanitary facilities and the rooftop farm.
In any case, shoppers seem delighted with their new supermarket. According to information from Rewe, after 14 months sales already reached levels that were originally planned for the third year. Customers are even able to take a look at the food production areas. A spiral staircase leads up from the café to a viewing room on the roof where the production cycles are explained.
90 percent less water
In the first year, approx. 20,000 tilapias were farmed in the store’s 13 rooftop basins, together with 732,000 basil plants. Aquaponics allow basil and fish to grow in two symbiotic cycles that need 90 percent less water than in conventional farms.
The aquaculture cycle in fish production and the hydroponics cycle in plant production are mutually beneficial and provide each other with water, nutrients and fertilizer.
The Rewe Green Farming supermarket has been certified with the Platinum seal for sustainable construction from the German Sustainable Building Council (DGNB). Experiences in Wiesbaden will be developed by the supermarket giant into a standard concept for interconnecting retail and production, with a subsequent rollout across Germany.
Text: Gertraud Gerst
Translation: Rosemary Bridger-Lippe
Photos: REWE / Jürgen Arlt, Holzbau Amann, ACME