TerraRad Tech AG and partners deploy a drone-mounted miniaturised microwave moisture sensor in Switzerland; Up to 30% water savings.
Agricultural innovation: A more sustainable use of water
Interviews, Videos & Guest Articles Published on 28 August 2026
Agricultural innovation: A more sustainable use of water
This summer’s repeated heatwaves and persistent drought have put increasing pressure on water resources, leading to restrictions in parts of Switzerland. This issue is particularly pressing in agriculture, where using water efficiently requires knowing when and where irrigation is needed. In an Innosuisse-supported innovation project, TerraRad Tech AG worked with ETH Zurich, WSL and Agroscope to develop and test a miniaturised microwave sensor that measures moisture in soil and vegetation. TerraRad Tech AG CEO, Derek Houtz, explains how it works and what the project revealed.
What agricultural challenge does your innovation project aim to address, and why is it particularly relevant today?
Derek Houtz, CEO of TerraRad Tech AG : Agriculture needs more precise information about soil and crop moisture to optimise irrigation and determine the best time to harvest cereals such as wheat and barley. By combining data from two types of microwave sensors, we can obtain information about soil moisture and the water content of vegetation.
During our Innosuisse-supported innovation project, the miniaturised sensor was mounted on a drone to collect moisture data across fields. This high-resolution data could help farmers adapt irrigation to local conditions.
Accurate information about kernel moisture can also support harvest timing. Kernels that are too dry have a lower weight, while kernels that are too wet are more susceptible to mould or fungi during the drying process.
The project also led us to identify a potential application for the miniaturised sensor in the turfgrass sector, where it could be used with small or autonomous mowers to measure moisture levels.
In simple terms, how does the miniaturised microwave radiometer work, and what information could it provide to farmers?
The C-band radiometer, one of the two types of microwave sensors, measures microwaves that are naturally emitted by crops, particularly by the kernels sitting at the top of cereal plants. The intensity of these emissions varies depending on the amount of moisture present.
Kernel moisture is particularly important when determining the right time to harvest cereals. If it is too dry, the harvest weight is not as high and the overall yield is decreased, if it is too wet, there is a considerably higher risk of mould or fungi affecting the dry weight of the yield.
For turfgrass management, the sensor enables portable moisture mapping using walking mowers or small autonomous machines.
How can more precise moisture data contribute to a more sustainable use of water?
High-resolution soil moisture data can show how moisture levels vary within a field or grassed area. This information can be used to adapt irrigation more closely to local conditions and avoid applying the same amount of water everywhere.
When paired with a modern irrigation system, this approach has the potential to reduce agricultural water use by up to 30%.
What positive effects could the innovative solution have for farmers and other people working in agriculture?
Combining the measurements provided by the two sensors could help farmers optimise irrigation and determine the best time to harvest cereal crops such as wheat and barley.
For turfgrass management, mapping soil moisture on putting greens, sports fields or public grassed areas using small autonomous mowers could support more targeted irrigation.
What did the project reveal about the technology’s environmental potential and the challenges that remain?
The research conducted during the Innosuisse project identified several challenges. Further development of the algorithm is required before kernel moisture can be measured remotely with sufficient accuracy across different environmental conditions, soils and crops.
Factors such as soil and crop temperature, the angle of cereal spikes as they dry, and changes in surface roughness caused by precipitation created more uncertainty than expected.
At the same time, the project highlighted the water-saving potential of passive microwave sensing for turfgrass applications. With our existing sensor, we have already observed water savings amounting to tens of millions of litres per year at a single gold course in a desert environment. While this figure is specific to arid conditions and is not directly transferable to Switzerland, it illustrates the technology’s potential. The miniaturised sensor could make this approach suitable for small autonomous mowers and enable more regular moisture mapping.
How do the different project partners contribute to the development and validation of the solution?
ETH Zurich contributed to the development and testing of the hardware. We presented the radiometer prototype and the initial results in a conference paper at the International Geoscience and Remote Sensing Symposium in 2023.
The Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) contributed with modelling of vegetation emission based on its structure and physical parameters. This work was novel within the microwave-modelling community and could also contribute to satellite remote-sensing algorithms and similar future applications involving radiometers and radars.
Finally, Agroscope contributed to the agricultural knowledge, experience, and field measurement setup. Its contributions included experimental design, control plots, in-situ measurements and a rainout shelter used to control moisture levels.
What role has Innosuisse’s support played in making this innovation project possible?
Innosuisse supported us through its innovation project with implementation partner funding. It recognised the potential of the technology and the collaboration between the different institutions.
Its funding enabled us to develop and test the sensor together with ETH Zurich, WSL and Agroscope and to investigate a novel application in agricultural technology.
What are the next steps for bringing this Innosuisse-supported innovation to market?
The next step is to prepare the miniaturised sensor for commercialisation. This includes adapting the design for manufacturing, finalising the housing and developing the assembly plans.
We plan to integrate the sensor into autonomous mowers and offer universal mounting kits for different types of machines.
We are also working on an integration that could enable irrigation systems to automatically adjust water use based on data from our soil moisture sensors.
Founded in 2020, TerraRad is a growing start-up specialising in environmental remote sensing technologies. Its mission is to provide advanced solutions for mapping soil moisture to conserve natural resources and optimize environmental conditions.