Yet a group of researchers in Europe and Asia say they have found a surprising way forward, turning the planet’s most “useless” sand – that of the desert – into a new kind of concrete that could ease pressure on fragile coastlines and cut part of the sector’s carbon footprint.
The hidden sand crisis behind our cities
Skyscrapers, motorways, wind turbine bases, metro lines, even smartphone screens: almost all of them depend on sand. Not the golden postcard beaches of holiday brochures, but construction-grade sand with sharp, angular grains that bind well with cement.
In just six decades, global sand consumption has tripled. The building sector alone now drives the use of around 50 billion tonnes of sand every year. That is more material than any other raw resource on Earth after water.
Geology cannot keep pace. Natural sand takes hundreds of thousands of years to form as rock slowly erodes, fractures and is carried by rivers. Humanity is extracting it in mere decades.
As inland reserves shrink, mining companies have moved to riverbeds, coastal dunes and the seabed. The result is a cascade of knock-on effects: eroding beaches, collapsing riverbanks, damaged marine habitats and saltwater creeping into freshwater aquifers.
Construction sand is being used up far faster than geological processes can replenish it, turning a humble grain into a strategic resource.
Several countries have already seen a rise in illegal sand mining, from West Africa to Southeast Asia, feeding a black market worth hundreds of millions of dollars. Local communities are left with destroyed fisheries, vanishing beaches and increased flood risk.
Why desert sand has always been ruled out
At first glance, using desert sand sounds like the obvious fix. Deserts cover about 20% of the world’s land surface. The Sahara alone is larger than the United States. So why are we not already building with it?
The answer lies in the shape and texture of the grains. In standard concrete, sand plays a mechanical role. The grains are slightly angular and rough. They interlock like tiny bricks. Cement then hardens around this compact skeleton.
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Desert sand grains have lived a very different life. They have been rolled and blasted by wind for thousands of years. This constant abrasion polishes them into smooth, rounded spheres.
Desert sand behaves more like millions of microscopic ball bearings than like a stable skeleton for concrete.
These polished grains slide over each other instead of locking together. When you try to use them in normal concrete recipes, the mix is weak and crumbly. The more you add, the worse the performance.
For decades, engineers simply wrote off desert sand as “too fine and too round” for serious construction. Coastal, river and quarry sands remained the go-to option, with all the environmental damage that brings.
A radical idea: concrete with almost no cement
Research teams from the Norwegian University of Science and Technology and the University of Tokyo decided to challenge this assumption. Instead of forcing desert sand to work with conventional cement, they rewrote the recipe from scratch.
The concept they developed has a slightly sci‑fi name: “botanical sandcrete”. At its core, the idea is surprisingly straightforward: cut back sharply on cement and use plant-based binders combined with very fine wood particles.
In laboratory trials in Tokyo, the researchers mixed desert sand with a cocktail of organic additives, including biomass-derived binders and powdered wood. This mixture was then placed in moulds and subjected to carefully controlled cycles of heat and pressure.
Under these conditions, the plant-based compounds soften, flow and then set, gluing the sand grains together into a solid, stone-like block. The wood particles act both as a filler and as a kind of internal micro‑reinforcement.
Adapting the process to the sand, not the other way round
Conventional concrete technology is built around cement chemistry. This time, researchers flipped the logic: they tailored the process to the specific behaviour of desert sand.
Because the grains are round and fine, the team adjusted the ratios to make sure the organic binders could flow between them and coat them effectively. They also tuned the pressing pressure so that the grains pack as densely as possible without crushing.
By changing the recipe and the manufacturing steps, the “wrong kind” of sand begins to function as a resource rather than a waste.
Through dozens of test batches, the researchers varied three main levers:
- Temperature: to optimise how the organic binders soften and cure
- Pressure: to compact the sand and expel excess air
- Pressing time: to allow stable chemical bonds to form
The result is not traditional concrete in the strict sense. It is a new category of composite material that behaves in some ways like concrete but relies on very different internal chemistry.
What this new material can actually do
Early tests suggest that botanical sandcrete can reach mechanical strength levels suitable for a range of non‑structural uses. That means applications where failure would be inconvenient or costly, but not life‑threatening, such as:
- Outdoor paving slabs and pedestrian walkways
- Garden and park tiles
- Low curbs and edging elements
- Urban furniture, like benches or planters
- Cladding panels where the load is modest
For now, no one is pretending that this material can replace steel‑reinforced concrete in bridges or high‑rise towers. Its long‑term behaviour under heavy loads, frost, humidity and UV radiation still needs rigorous testing.
| Property | Traditional concrete | Botanical sandcrete (lab stage) |
|---|---|---|
| Main binder | Portland cement (clinker) | Plant-based binders and additives |
| Sand type | River, coastal or quarry sand | Fine desert sand |
| Typical use | Structural and non‑structural | Non‑structural (pavers, tiles, light elements) |
| CO₂ footprint of binder | Very high | Lower, depending on biomass source |
Researchers stress that they are at the prototype stage. Before any mass rollout, they will need to examine durability in different climates, resistance to water infiltration, potential biological degradation of the plant components and compatibility with existing construction standards.
Climate stakes: why every experiment counts
Cement production, the backbone of classic concrete, is one of the most carbon-intensive industrial processes on the planet. It accounts for roughly 8% of global CO₂ emissions. That is more than aviation and shipping combined.
The problem lies not only in the fuel burned to heat cement kilns, but also in the chemical reaction itself. When limestone is transformed into clinker, it releases huge amounts of carbon dioxide locked in the rock.
Any serious cut in cement demand, even limited to certain uses, can have a measurable impact on global emissions over time.
Botanical sandcrete does not make cement obsolete. But by reducing the need for cement in specific, high‑volume products such as paving blocks and urban tiles, it can chip away at demand. If entire categories of low‑risk elements switch to this technology, the avoided CO₂ could add up quickly.
There is another climate angle: coastal sand mining weakens natural barriers against storms and rising seas. Creating an outlet for desert sand lessens pressure on beaches and river deltas that currently act as front‑line defences against climate impacts.
From lab to desert: what a real‑world rollout might look like
On paper, desert nations stand to gain the most: they hold the raw material in virtually unlimited quantities. But deployment will not be automatic. Several conditions must be met.
First, biomass sources for the botanical binders need to be locally available and managed sustainably. In arid regions, that may mean using agricultural residues, fast‑growing hardy shrubs, or imported biomass from nearby wetter zones.
Second, the process requires precise temperature and pressure control. That implies small factories equipped with presses and heat treatment units, likely powered by electricity. In sunny regions, solar power could offset much of this energy demand.
Third, construction codes must evolve. Engineering standards currently specify known concretes and mortars. Certifying a new material, especially one with organic content, involves years of tests, paperwork and cautious pilot projects.
One plausible scenario is that botanical sandcrete first appears in niche, controlled environments: eco‑resorts, university campuses, industrial sites run by the same company that operates the pilot plant. As confidence builds, municipalities could start using the material for pavements and parks.
How this fits with other sand and cement solutions
Botanical sandcrete sits alongside, not above, a suite of other ideas aimed at easing the sand and cement crunch:
- Recycled aggregates: crushing old concrete and reusing the sand‑like fraction in new mixes
- Alternative binders: geopolymers and industrial by‑products such as fly ash and slag to replace clinker
- Stricter mining rules: better monitoring of river and coastal sand extraction and bans in sensitive zones
- 3D‑printed structures: optimised shapes that use far less material for the same or better strength
- Design efficiency: lighter structural designs and more modular buildings that cut total concrete use
No single technology will “fix” the sand crisis. The likely future is a patchwork: more recycling in wealthy countries, alternative binders in regions with heavy industry, strict mining bans in damaged ecosystems and new composite materials like botanical sandcrete wherever conditions allow.
Key terms and what they really mean
Two technical expressions keep popping up in this conversation: “non‑structural use” and “biobased binder”. Both deserve a clear, plain‑language explanation.
Non‑structural use simply refers to elements that do not carry the main loads of a building or piece of infrastructure. A paving slab, a decorative façade panel or a garden step falls into this group. A concrete column, bridge deck or dam wall does not. New materials almost always start in the non‑structural category, where the safety stakes are lower and performance requirements are easier to meet.
Biobased binder means a substance that binds particles together and comes partly or fully from plants. In this case, it could be derivatives of lignin or cellulose (components of wood and other plants), or resins produced from agricultural by‑products. The climate benefit depends heavily on how that biomass is grown, processed and transported.
Risks, trade‑offs and the road ahead
Turning desert sand into a resource brings its own set of questions. Over‑extraction is less of a concern than with rivers or coasts, but desert ecosystems are not empty. Vehicle traffic, dust and localised mining can disturb wildlife and fragile soils.
There is also a social angle. Countries currently exporting coastal sand, often at high environmental cost, could see that market shrink. That might hit some local economies unless governments anticipate the shift and support alternative livelihoods.
On the flipside, countries rich in desert landscapes – from North Africa to the Arabian Peninsula and parts of China, India and Australia – could reduce import bills for construction materials. In regions facing fast‑growing cities, a local, lower‑carbon paving material could free up cement supplies for structures where there is no easy substitute yet.
If the 2020s are remembered as the decade when cement, steel and plastics finally faced real competition, botanical sandcrete will likely feature as one of many small but telling signs that the construction industry is starting to rethink not just how much it builds, but what it builds with.
