An electrowetting module (20) comprises a fluid chamber (8) which contains a first fluid (A) and a second fluid (B), which are separated by an interface (14) , and means (16, 17) to exert a force on at least one of the fluids to change the position and/or shape of the interface. By providing the second fluid body with a dissolved or mixed compound, being insoluble in or immiscible with the first fluid body, and/or the first fluid body comprises a dissolved or mixed compound being insoluble in or immiscible with the second fluid body, in amounts sufficient for lowering the freezing point of the respective fluids to below -20.degree. C., the performance of the module can be improved so that the module can be used at low temperatures.