The Project

Sustainability was key to every aspect of the Dutch pavilion at the Expo 2020 in Dubai. All features of an expo pavilion that are traditionally unsustainable were transformed using eco-friendly methods. The steel that was used to build the stand was rented from the Dubai construction industry to be re-used after the show. On a floor made out of mushrooms stood a food cone, encircled with more than 3000 edible plants. The sunlight needed for the plants was filtered through solar panels on the roof.

But when designing a structure that incorporates thousands of plants, one crucial question remained: how can the plants be watered sustainably in a desert that receives an average of 68mm of rainfall per year?

The Solution

Designer Ap Verheggen delivered the solution by supplying the innovative ‘SunGlacier’, a solar-powered rain shower that can harvest hundreds of litres of water every day from the desert air.

Using sunshine, gravity and air, SunGlacier can create fresh, clean drinking water in almost any climate on Earth. The system utilises the ‘growing waterfall principle’, condensing water vapor in cold falling air. Up to 99% of water is dehumidified from the air and due to the unique design, nothing evaporates during the process.

At the Expo 2020 in Dubai with outside temperatures of over 40°C, the unit harvested 50l of water per hour. These results suggest incredible possibilities to use this system for providing drinking water and crop irrigation in dry areas.

Sunglacier's Control System

Precise control of the system is required in order to achieve maximum water output. Vink Koeltechniek, a Dutch cooling system specialist, designed and installed the control system that creates the optimal parameters for harvesting water. The system utilises Resource Data Management's (RDM's) Intuitive TDB controller - an HVAC controller with RDM's PLC software.

Vink Koeltechniek designed a PLC strategy that would lead to an optimised water harvest. The Intuitive TDB controls the entire process of harvesting water. It measures parameters such as temperature, pressure, humidity, and flow rate, and calculates the dew point based on outside relative humidity and temperature. These parameters are fed into the PLC strategy which then specifies the outputs which are also controlled by the Intuitive device. The outputs include compressor, fan and pump speed, stepper motor (expansion valve), three-way valve, motor run signals, indicator lamps, alarm signals, and solenoid valves.

“The great variety of possible inputs and outputs one can use with RDM is very helpful. This makes RDM a great partner for research and development projects.” – Vink Koeltechniek

When developing the control system for SunGlacier, Vink Koeltechniek continued to be impressed by many aspects of the RDM Intuitive controller which facilitated the design of the solution:

Free-to-Download PLC Desktop Editing Software

Intuitive TDB controllers are pre-loaded with RDM’s PLC software TDB. In addition, PLC desktop editing software – TDB Editor – is free to download. For Vink Koeltechniek, this meant they were able to optimise the control strategy needed to harvest as much water as possible from Dubai’s desert air.

“In order to generate the maximum benefit from resources, investment and energy, it is important to create optimal conditions and continuously recalculate parameters. With the use of RDM controllers, it is easy to measure, calculate, and control even complex mathematical formulas.” - Vink Koeltechniek
Built-In Data Logging

Every 15 minutes, Intuitive controllers log data of both their inputs and outputs and save it for months. If a USB stick is used, the frequency of data logging increases to 15 seconds and storage capacity extends to years.

For Vink Koeltechniek, this feature proved extremely useful. Using the data of all inputs – temperature, pressure, humidity and flow rate – as well as all outputs, they were able to optimise the PLC strategy on an ongoing basis. As the Expo 2020 continued, they further optimised SunGlacier’s water harvesting capabilities based on the data they received.

Remote Access to the Controller

All of RDM’s Intuitive controllers can be remotely controlled and monitored from anywhere with internet access. In this case, it allowed Vink Koeltechniek to monitor data and adjust PLC control strategies accordingly from their headquarters in the Netherlands, while the device was still active in Dubai.

Environmental Benefits

SunGlacier allows the user to harvest water even in dry desert areas. Together with water purifying techniques, it creates a stand-alone solution that is able to harvest drinking water in almost any place. The solution can provide fresh drinking water to people and animals and can be used for crop irrigation. The optimised control system, RDM’s Intuitive TDB, allows the SunGlacier solution to harvest as much water as possible from any outside condition.

“Our sustainable solar-powered water-from-air technology makes it possible for us to produce food in the future without being dependent on rainfall, rivers or other traditional water sources.” - Ap Verheggen – Designer of SunGlacier
Company Bio

Vink Koeltechniek has delivered cooling systems for commercial and industrial purposes, for the past 40 years. Based in the Netherlands near the city of Rotterdam, they operate internationally, adopting a personal and customised approach.