"TERRA project aims to develop, from TRL 3 to 5, a tandem electrocatalytic reactor (TER) coupling an oxidation reaction to a reduction reaction, with thus the great potential advantage of i) saving resources and energy (needed to produce the oxidant and reductants for the two separate reactions), and ii) intensify the process (reduce the nr. of steps, coupling two synthesis processes and especially eliminating those to prepare the oxidation and reduction agents). The proposal address one of SPIRE Roadmap Key Actions “New ways of targeting energy input via electrochemical”. The TER unit may be used in a large field of applications, but will be developed for a specific relevant case: the synthesis of PEF (PolyEthylene Furanoate), a next generation plastic. TERRA project aims to make a step forward in this process by coupling the FDCA and MEG synthesis in a single novel TER reactor, with relevant process intensification. Between the elements of innovation of the approach are: i) operation at higher T,P than ""conventional"" electrochemical devices for chemical manufacturing, ii) use of noble-metal-free electrocatalysts, iii) use of novel 3D-type electrodes to increase productivity, iv) use of electrode with modulation of activity, v) possibility to utilize external bias (from unused electrical renewable energy) to enhance flexibility of operations. In addition to scale-up reactor and test under environmental relevant conditions (TRL 5), the approach in TERRA project is to address the critical elements to pass from lab-scale experimentation to industrial prototype with intensified productivity. These developments are critical for a wider use of electrochemical manufacturing in chemical and process industries. "