OpenTCC: An open source low-cost temperature-control chamber

Microbial electrochemical technologies (MET) are emerging systems for environmental applications such as renewable energy production or pollution remediation. MET research often requires stable temperatures and low levels of electromagnetic interference. Due to the presence of electrical wires and sensors, heating MET using water jacket recirculation can raise safety issues, whereas heating coils may affect the results of electrochemical analyses. The proposed open-source temperature-control chamber (OpenTCC) aims to provide a low-cost solution for controlling temperature (in the range 20-55 °C) while simultaneously reducing the electromagnetic interferences caused by switching mode power supplies. OpenTCC consists of a light and cheap structure, incorporating eight heating pads and two Peltier-cooling modules powered by open-source electronic circuits. Its hardware is controlled by an Arduino microcontroller and a Python interface which provides data-logging and serve as a basis for programable temperature cycles. The system has a modular design to allow stacking several independent modules. OpenTCC provides a reliable and tunable temperature control at lower costs than currently available commercial temperature controllers and provides a platform for field-specific upgrades. Though optimized for MET, Open-TCC can be adapted to other laboratory applications due to its flexible design.