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Micro combined heat and power (micro‐CHP) systems can efficiently provide private homes or small commercial buildings with both heat and electricity. The European industry is ramping up demonstration of fuel cell based micro‐CHP units in the EU projects ene.field and PACE. Systems based on solid oxide fuel cells (SOFC) and polymer electrolyte membrane fuel cells (PEMFC) have been demonstrated. More than 1,000 units have been tested in 10 European countries in the years 2012–2017. In the coming 5 years, additionally 2,500 units will be deployed via the EU funded program PACE. These field trials have been accompanied by analyses of end‐user satisfaction, environmental impact, and costs involved. The end‐users participating in the field trials had a very positive perception of the fuel cell micro‐CHP technology. The environmental impact of fuel cell micro‐CHP was compared to that of heat pumps and gas condensing boilers in a life cycle assessment (LCA). The micro‐CHP units have a better environmental performance than these competing technologies in all the analyzed use‐cases. Today, the capital costs of fuel cell based micro‐CHP are significantly higher than that of traditional heating technologies. However, as serial production begins, economies of scale will cause the costs to drop substantially and the micro‐CHP can become economically competitive.

Commercial TaC and Si3N4 powders were tested as possible electrocatalyst support materials for the Oxygen Evolution Reaction (OER) for PEM water electrolysers, operating at elevated temperatures. TaC and Si3N4 were characterised by thermogravimmetric and differential thermal analysis for their thermal stability. The Adams fusion method was implemented to deposit IrO2 on the support surfaces. A series of electrocatalysts was prepared with a composition of (IrO2)x(TaC/ Si3N4)1-x,where x represents the mass fraction of IrO2 and was equal to 0.1 (only for TaC), 0.3, 0.5, 0.7, 0.9 and 1. The thin-film method was used for electrochemical analysis of the prepared electrocatalysts. SEM-EDX, BET and powder conductivity measurements were used as complementary techniques to complete characterisation of the electrocatalysts. Additionally, they were compared in their properties with previously reported data for a SiC-Si support. The stability of the electrocatalysts was assessed by estimation of reversibility of the anodic/cathodic processes.

Polymer electrolyte membrane (PEM) water electrolysis is a prospective method of producing hydrogen. We focused on one of its issues - the lack of a suitable support material for the anode electrocatalyst. TaC and NbC were studied as possible electrocatalyst supports for the PEM water electrolysis. Resistance to oxidation of the TaC and NbC was investigated by exposing them to air at 84 and 150 ºC. Subsequently, their electrical conductivity was measured as the indicator of oxidation. Change in specific surface area and conductivity was measured after different periods of ball milling. We found that the TaC was significantly more resistant to oxidation than the NbC. Eventually, both materials retained relatively high electrical conductivity even with the oxidized surface. TaC can thus be recommended as an electrocatalyst support for the oxygen evolution reaction and both materials are proposed to be tested as alternative electrocatalyst supports for the hydrogen evolution reaction.