Progressive meets Society – Interview with Stefano Lo Presti

Earth observation is a very powerful source of information […] We started to use it to support evaluation and decision-making processes in the public and private domains ranging from farming to golf and insurance sectors and we are continuing to use it successfully, developing new ideas and solutions every day.


Earth Observation data combined with weather, soil and agronomic data can be an advantage for farmers when it comes to monitor vegetation health. The use of a holistic approach integrating data of different nature and from different sources has been a key factor for Centrale Valutativa to develop an innovative tool, Tethys Smart Farming, aimed at better monitoring crops and supporting farmers’ decision-making. The tool brings direct economic benefits to farmers which can reduce management costs of crops while having a positive impact on the environment.

In this new interview for Progressive Meets Society, Stefano Lo Presti, Co-Founder & Managing Partner of Centrale Valutativa, shared with us the experience of the startup with the exploitation of satellite data, how their combination with data from other sources is an advantage compared to more traditional monitoring systems of crops and why the collaboration with Earth Observation experts has been important to properly use satellite data.

Stefano, first of all, can you please introduce Centrale Valutativa to our readers, how did you come up with your business idea and the work you are doing to support evaluation and decision-making processes?

SLP: Centrale Valutativa was founded 5 years ago with the initial objective of offering services on the evaluation of public policies, especially in the agricultural field. That had been our work for the previous 20 years, during which we had used and developed new tools for evaluating EU policies in the agro-environmental field, including satellite imagery.

Whether we have to evaluate the effects of a policy or to understand a specific phenomenon, such as the water needs of a plant, it is necessary to have data and information that can describe it accurately. Earth observation is a very powerful source of information, even if it must be processed and, above all, interpreted in the right way. We started to use it to support evaluation and decision-making processes in the public and private domains ranging from farming to golf and insurance sectors, and we are continuing to use it successfully, developing new ideas and solutions every day.

For the evaluation of the Rural Development Programmes of the Common Agricultural Policy – CAP we are now studying how to assess the amount of the subsidies to be given to farmers who convert their farms to eco-sustainable practices such as organic farming, integrated farming, conservation agriculture, etc. This is done by calculating the yield differential that is obtained between the different cultivation techniques. We are also working on the calculation of the drought or hail damage basing on earth observation data in order to improve the accuracy of the public compensation given to the damaged farms.

Let’s take a closer look at the work you do with earth observation data. CENTRALE VALUTATIVA developed TETHYS SMART FARMING, a tool that thanks to the processing of satellite images is able to provide farmers with useful information for a more modern, efficient and sustainable management of their farms. Which are the main objectives of this service?

SLP: The main goal of Tethys Smart Farming is to provide a tool to support the farmer’s decision making. It consists in three services to the farmer:

Tethys crop monitor detects in advance the onset of stress conditions (phytophages, cryptogamic diseases, water shortage, nutritional deficiencies). The instrument allows to monitor the growth of the crop and to control its vegetative status.
Tethys water saver allows you to estimate the amount of water lost from the crops due to evaporation and transpiration and therefore the need for water replenishment useful to maintain the status of the crop itself. The system defines when, how much and where to irrigate.
Tethys yield estimator estimates crop yield, the system produces prescription maps useful to understand which are the most productive and which are the less productive areas of the field under study.

At the moment we are studying a service on variable rate fertilization, in order to optimize the use of fertilizers saving money and reducing water pollution.

From precision farming to smart farming: what sort of technologies and satellite data have you used for TETHYS SMART FARMING and how have you used them?

SLP: TETHYS SMART FARMING uses data of different nature and origin: weather data, soil and agronomic data and obviously earth observation data, which are integrated according to a holistic approach and processed through dynamic agronomic models. Depending on the service we use different data:

Tethys Crop Monitor uses vegetation indices such as NDVI, NDWI and biophysical indices such as LAI, fCOVER. Every time Sentinel 2 and Landsat 7 and 8 pass by, we produce maps and the variation of the index compared to the previous survey and we also produce graphs of their trend over time.

Tethys Water Saver is based on the dynamic mathematical model SEBAL (Surface Energy Balance Algorithm for Land), developed by Wageningen University in the Netherlands, systematizing meteorological and pedological satellite data. In this case we only use Landsat 7 and 8 as the algorithm provides for the use of the thermal sensor that Sentinel does not have.

Tethys Yield Estimator is based on the evapotranspiration of the crop obtained with the SEBAL model, the fPAR (a biophysical index) and other parameters characteristic of each crop.

The study we are conducting on fertilization optimization, which is still in the experimental phase, is based on prescription maps, biomass produced at the time of fertilization and fCOVER, a biophysical index that provides useful information on crop growth.

You mentioned that data of different nature were integrated according to a holistic approach. Why was the combination of satellite data with weather, soil and agronomic data an advantage compared to more traditional monitoring systems of crops health?

SLP: In the agricultural world the use of new technologies is still limited, the farmer is very bound to traditional tools and to his experience. Lately, however, things are slowly evolving as a function of the generational change we are witnessing and under the pressure of climate change. The latter are undermining some of the certainties of farmers. Only through tools such as Tethys which integrates Earth Observation data, farmers will be able to better and promptly understand what is happening to crops, and will be able to prevent abnormal situations related to climate change. In this sense, Tethys represents a tool for farmers to adapt to climate change.

Based on your experience, which have been the main benefits reported from farmers using TETHYS SMART FARMING?

SLP: Benefits are both economic and environmental.
From an economic point of view, farmers could lower the costs in monitoring crop health while increasing in yields. This means reduced time in the field to see how the crop is doing and reduced fertilizer and water use.
The environmental benefits are related to less water use and less energy expenditure to pump the water, resulting in a reduction of greenhouse gas emissions. The lower use of fertilizers results in a lower risk of water pollution and reduces nitrous oxide emissions. Just consider that a greenhouse gas is 298 times more climate-changing than CO2.

Earlier in the interview, you said that Earth Observation data must be processed and, above all, interpreted in the right way. How did cooperation with experts in the Earth Observation sector facilitate the access to and exploitation of satellite data?

SLP: Centrale Valutativa has been incubated at ESA-BIC for five years and in this framework we also collaborated with the ESA Research and Service Support service operated by Progressive Systems. Although we are a multidisciplinary team composed by agronomists, GIS experts, economists and statisticians, we have had the opportunity to learn through training courses how to use satellite images, how to interpret the results they give and how to do business. There is still a long way to go, but we are on the right track.

A long way to go that offers a wealth of opportunities. By looking at the future, where do you see CENTRALE VALUTATIVA in 10 years from now? Are you planning to use earth observation data for other projects in the future?

SLP: Difficult question, clearly we hope that many farmers will use our services. I think that although it is something new and for many people still unknown, in a few years many farmers will be familiar with such tools and will use them more extensively, contributing to a more conscious and sustainable agriculture.
In the future, if ESA or NASA launch hyperspectral satellites, we will be able to work on particular plant diseases and identify weeds in order to target weed control and reduce the use of pesticides.

Stefano, thank you very much for your time and for sharing the experience of Centrale Valutativa with us. For a close, building on your experience, which piece of advice would you give to a young and innovative start up in 2021 that is taking the first steps in the Earth Observation sector and is willing to exploit satellite data for their business?

SLP: I would tell that Earth Observation is a new science that gives a lot of opportunities, don’t give up at the first difficulties: it is hard work but enjoyable and very satisfying.

To learn more about Stefano Lo Presti:

Stefano Lo Presti is currently co-founder and managing partner of Centrale Valutativa S.r.l, dealing with agricultural engineering since 1993. He has carried out for ten years’ research in food technology at the University of Tuscia and the University “La Sapienza” of Rome, and in 1998 he obtained a PhD in food biotechnology. He worked at Agriconsulting Company since 1997 where he was responsible and coordinator of the assessment of the environmental effects of rural development programs. He gained experience in the analysis of the environmental effects of agriculture; in particular, on the topics of: water quality, irrigation system, erosion and climate change mitigation and adaptation. He was in charge of water management at the level of “Consorzi di Bonifica”, and uses spatial analysis technologies based on Geographic Information System (GIS). He is currently project manager of Tethys Smart Farming.