The EU has the long-term goal to reduce greenhouse gas emissions by 80% to 95% compared to 1990 levels by 2050. This is only possible by introducing more shares of renewable energy sources in the energy systems, such as wind, solar, and (waste) biomass. With a high degree of energy produced by fluctuating sources such as wind and solar, the energy system will inevitably require technologies that produce electricity in times of lack and store electricity in periods of excess electricity supply from renewable sources and that provide green fuels for the heavy transport sector and industry.
Solid oxide technologies (SOC: SOFC & SOE) are key enabling technologies for allowing the transformation of the energy systems from fossil based fuels to renewables in order to reach sustainable development goals. SOCs are an efficient link between sectors: power, gas/fuel, heat. SOC can therefore emerge as key players in the energy transition and in sustainable energy systems in many concepts, such as
• fuel/gas to power and heat at small to large scale,
• energy storage through power to hydrogen/fuel,
• utilisation and upgrading of biogas,
• balancing of intermittent electricity from renewable sources through load following and reversible operation, and
• central and decentral solutions for electricity and heat production.
Important advantages of SOCs are:
• High efficiencies to convert a fuel (like hydrogen) into electricity (>60%) in fuel cell mode and electricity to fuel (like hydrogen) (~100%) in electrolysis mode
• Flexibility regarding used gasses and higher impurity tolerance as compared to low temperature fuel and electrolysis cells
• Possibility to operate the same unit in fuel cell and electrolysis modes (reversible SOC).
First commercial units are available on the market based on state-of-the-art (SoA) materials. In order to reach large-scale market breakthrough and economic competitiveness, SOCs need to become cheaper and reach longer lifetimes.
The NewSOC project addresses those challenges by proposing twelve concepts to improve SoA SOCs aiming at a competitive next generation technology. The concepts cover the following areas: (i) structural optimisation and innovative architectures based on SoA materials, (ii) alternative materials, which allow for overcoming inherent challenges of SoA, (iii) innovative manufacturing to reduce critical raw materials and to reduce the environmental footprint at improved performance & lifetime.
The NewSOC project reached the overall objectives:
25% Increase of the applicable electrolysis current at degradation rates below 1%/1000 h
25% Reduction of the area specific resistance
25% Increase of cycling stability for reversible operation, thermal and load cycling
25% Reduction of cell manufacturing costs, and
25% Reduction of toxic organics or materials during manufacture.
The NewSOC project validated the new cells & stacks at the level of large cells with > 50 cm2 active area and short-stacks in close collaboration with industry, thereby moving the technology readiness level (TRL) from 2 to 4.
The NewSOC project provided a path on how to increase the TRL level beyond the project period towards TRL of 6. Furthermore, the NewSOC project evaluated the new SOC materials and fabrication processes with both a life cycle impact and cost assessment including interpretation through the eco-efficiency framework.
