An interview with the inventors of miniMET

miniMET is a new citizen science weather station project being developed by AEMET, Spain’s state meteorological agency.

It involves the development of Raspberry Pi weather stations by schools and linking them all in a network. Students will be able to build their own weather stations with little equipment and send their data directly to AEMET.

We talked to the promoter of the project, Fernando Asanza, to find out how he got the idea and how it all works.

Father and son, the guys who dreamed up the miniMET Project


How did you get the idea for the miniMET project?

At the very beginning of 2014, I was looking for a new way of encouraging my 12-year-old son Samuel, a good student who is passionate about video games and YouTube, to explore more creative and educational aspects of computer technology.

So I put together two elements: the new Raspberry Pi, a credit card size computer, and free software, GNU/Linux MAX, based on Ubuntu Linux, that was being installed in all public schools in Madrid.

To help spread the word I set up a blog called RasPiMAX, acronym of Raspberry Pi with Linux MAX. A few months later I begun to collaborate with the MAX Group, a team of developers from the Ministry of Education, Youth and Sport of the Community of Madrid, who welcomed my ideas with enthusiasm, as putting Linux Max into a Raspberry Pi would help to introduce both of them to young people at schools. This broadened the scope to all students of Madrid schools.

Raspberry Pi boards (Zero W on the left, 3B on the right)


Why did you choose Raspberry Pi and how did it develop into the miniMET Project?

The Raspberry Pi is a great way of introducing young people to programming and it is very easy to connect it to all kinds of affordable accessories like lcd displays, joysticks, LEDs and, of course, sensors of parameters like pressure, temperature, humidity, luminosity and air quality, among others.

Testing temperature and pressure sensors with a LCD display

After a while teaching Sam to use the Linux system and its applications, we started to work using the communication ports on the Raspberry Pi to connect with many devices and sensors.

Joining several weather sensors to make a Raspberry Pi weather station was then only a matter of time and so the miniMET station began to take shape. Over the last three years we have developed up to three different versions of weather station.

2014: miniMET I project

2015: miniMET II project

2016: miniMET III project has two versions, with Raspberry Pi 3B and the Zero W, both with the same shelter


How did you involve Spain’s state meteorological agency, AEMET?

With the miniMET III station almost finished, I was wondering where I could test it further and so I decided to try it in the best possible place I could imagine, AEMET, where I had also been working for many years.

As I had already devised the idea of a network of school observatories, I decided to present my project to AEMET, not only to test the station itself, but also to see if they would be interested in jointly developing the project further. It so happened that at that time AEMET were looking for ideas to start new citizen science projects and so the miniMET project was adopted.

I am really excited and never dreamt that, what started as a way of encouraging my son to learn programming, became a real project three years afterwards. In addition, the development and leadership of such an innovative project at AEMET will be a great personal and professional challenge for me.

When will the project start? How many schools are participating?

At the present moment, the project is being defined in its last details with several phases up to the end of 2018. It includes the final definition of the prototype, further tests, development of manuals, the design of the data management through AEMET opendata and developing a way of visualizing the data online.

There are several volunteers including schools, environmental centres and even amateur meteorologists who are willing to participate in this prototype phase, so I hope to begin with at least ten of them by the end of 2017.

On this AEMET terrace all kind of weather stations are being tested


How will volunteers develop their miniMET stations?

Speaking about school teams, educational environmental centers and individuals, the project is about doing it all by themselves. As a technology project it begins in a workshop. Schools will buy components, build the station, program it and set it operationally in place.

All components of the project are sold in local stores or on the Internet

Finally they will have to connect it to the net and begin sending observation data. Then they will see their station and their observations displayed on an internet-based map.

AEMET will provide them with full documentation, lists and costs for electronic components and materials, where to buy them and how to build it and set it up. Volunteers will also download and install the software, which will be developed by us. They will be assisted by AEMET’s people responsible for the project, with forums, e-learning techniques and even on-line assistance. We are thinking about all possibilities including visiting schools to help and check the miniMET stations in-situ.

This is a living and evolving project. We bring everyone the instructions to mount an initial prototype to publicly launch the project, but we will be encouraging students to research, innovate and improve it, showing their results in annual competitions. The best, most innovative ideas could be incorporated into AEMET’s next station version and its corresponding manuals.

So users will not only cooperate by sending us their observation data but also by improving the weather station itself. This includes the software, if someone thinks they can improve it, or if someone has ideas for better ways of visualizing the data on the map. We really want to share the project with everyone in all aspects, in order to make them co-responsible of it. This is a key value of citizen science.

We also want to involve the official education community in many ways such as development of environmentally-related teaching materials, regarding weather and climate among others – according to each school level – encouraging and supporting schools to participate.

Sam and Fernando testing sensors with python programming


To Samuel: what is your favourite thing about Raspberry Pi, why do you like it, how do you generally use it?

Well, first of all, it should be made clear that the Raspberry Pi is far from the performance of a PC and therefore I do not try to use it for bulky work or games and tasks too demanding in processing or graphics capabilities.

However, and this is what I like most about it, it has all PC technology, all computational and communications possibilities, with those mentioned restrictions of speed, memory and storage.

This means, and that’s what I’m using it for, I can learn with it everything related to computing, both hardware and software, in a really fun way. I’m learning a lot of things, some very advanced, really useful later, when I use a regular PC, either with Windows or with Linux MAX, like those ones at school.

For example, I am learning programming, either with Scratch that helps me to visually understand how a program works, dragging and fitting functional blocks on the screen, or with Python, which is also popular in the Raspberry Pi community.

But in addition to free software advantages, being open hardware implies that it is well documented and I can thus know and take full advantage of it, as in the case of the miniMET weather station, testing all kind of sensors using Python programming. With few lines of code I can read temperature or pressure in the respective sensor. I can display those values on the screen, store them or even send them over the net.

In short, the Raspberry Pi is a very affordable computer, a small PC fully functional though not so powerful, in which everything is intended to education, to learning computing for every age. Besides that, is also a very creative and fun hobby.

For further information please see:

The miniMET informational web:

If you would like to help with translations please contact:, project email:


About the Author

Mara Dambour

Mara Dambour

Learning Zone Writer

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