# Automated Low Investment Cost Evaporometers (ALICEs)
## 5 Conclusions  
The presented system in its current form was tested, the device worked properly and fulfilled the requirements of evaporation measurement for evaporation research. The use of open-source electronics reduced the cost of the device well below the cost of devices available on the market. The cost of the components and the material to make one device can be around EUR 20. This does not include work and does not include basic electrotechnical tools and materials such as wires.  
The precision of the 3D printing allowed the creation of this device. Setting of the 50 stainless steel needles would be time consuming and difficult without a 3D printed assembly jig. Furthermore, drilling of the circuit board was carried out via another 3D printing jig. The circuit board is another component requiring high precision. Holes for the Arduino and sub-board connectors were spaced 2.54 mm apart. Manual positioning of the circuit board in the drill, with such precision, would be highly difficult.  
The technology of the device is based on a combination of 3D printing and a simple measuring microcontroller, in this case based on the Arduino platform, which provides the possibility of a connection with a set of other environmental values. Data collection and storage can be carried out remotely with WIFI or GSM modules.  
3D printing offers a very useful way to create complex devices for hydrological research. The inert nature of plastics is useful for the construction of devices partially immersed in a water environment. The insulating properties of 3D printed plastics are also viable in cooperation with electronics. In general, the use of 3D printers allows the design to be changed rapidly and to be adapted to different needs. Precise positioning of the contact needles via a 3D printed jig allowed high resolution of the water level measurements. Quite good data were therefore obtained during the experimental measurements. These data show the gradual decrease in the water level over time, which followed the real evaporation of water from the testing evaporation pan. In field conditions, this evaporation pan should be accompanied by a rain gauge, a wind velocity meter, and other climate measurement devices. This setup allows evapotranspiration to be calculated via the evapotranspiration coefficient.  
The following are available online at [[https://www.mdpi.com/article/10.3390/app11114986/s1](https://www.mdpi.com/article/10.3390/app11114986/s1)]([https://www.mdpi.com/article/10.3390/app11114986/s1](https://www.mdpi.com/article/10.3390/app11114986/s1)), 3D model of the 3D printed parts in.stl format and Arduino code.  
All authors participated in testing and conducting measurements on the small rainfall simulator and writing this article together. All authors have read and agreed to the published version of the manuscript.  
The research is funded by the Technological Agency of the Czech Republic (research project TJ02000351-Development of Tools and Methods Improving Estimation of Annual Evaporation Balance) and by the Student Grant Competition of CTU in Prague (research project-SGS20/156/OHK1/ 3T/11-Monitoring, experiments, and mathematical modelling of rainfall runoff and soil erosion processes).  
Not applicable.  
The authors declare no conflict of interest and the funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.