Community Research and Development Information Service - CORDIS


FlexiFuel-SOFC Report Summary

Project ID: 641229

Periodic Reporting for period 1 - FlexiFuel-SOFC (Development of a new and highly efficient micro-scale CHP system based on fuel-flexible gasification and a SOFC)

Reporting period: 2015-05-01 to 2016-10-31

Summary of the context and overall objectives of the project

The FlexiFuel-SOFC project aims at the development of an innovative, highly efficient and fuel-flexible micro-scale biomass CHP technology consisting of a small-scale fixed-bed updraft gasifier, a gas cleaning unit and a solid oxide fuel cell (SOFC). The technology shall be developed for a capacity range of 25 to 150 kW (fuel power) and thus be applicable for micro-scale CHP applications.
To reach this overall goal the project focuses on several specific objectives. An existing, already for heating purposes successfully demonstrated small-scale fixed-bed updraft gasifier technology is further developed towards enhanced fuel flexibility and integration into a SOFC based CHP system. Thereby, the further enlargement of the fuel spectrum applicable in the gasifier from softwood pellets and wood chips to wood chips from short rotation coppice (SRC, e.g.: willow, poplar) and selected agricultural fuels such as olive stones, nut shells and agro-pellets plays a central role. Moreover, a compact gas cleaning concept covering particle precipitation, removal of HCl, H2S and other sulphur compounds as well as tar cracking is developed. The aim is to provide a product gas with no PM, H2S contents <1 ppm and HCl contents <5 ppm as well as to upgrade the tar rich product gas by cracking specific tar compounds which cannot be converted by reforming in the fuel cell system. Last but not least, a SOFC technology enabling an operation at nearly atmospheric pressure, a defined temperature range of the product gas (700 to 800°C), a high power density as well as cost efficiency of the SOFC stacks and a high electric efficiency (stack efficiency of about 40% with product gas from the updraft gasifier) is developed.
With this new CHP technology an almost equal-zero emission (regarding CO, OGC, NOx, HCl, SOx, PAH and PM and due to the utilisation of biomass also regarding CO2) fuel-flexible heat and power generation with an overall efficiencies of close to 90% is envisaged. Therefore, two testing plants, a basic and an advanced one are developed, manufactured and assembled. The performance and evaluation of test runs with different biomass fuels at these testing plants shall form the basis to finally achieve an optimised system design at project end. Accompanying risk assessments, safety analyses, techno-economic and environmental impact assessments as well as market studies shall assure that the new technology resulting from the project also is market competitive.
In order to achieve these ambitious goals a multidisciplinary consortium consisting of a biomass conversion technology provider (WHtech), an engineering company specialised on the development of energetic biomass conversion systems (BIOS), specialists regarding gas cleaning (TUD, HyGear) and fuel cell technologies (IKTS, AVL) as well as partners experienced in market studies and techno-economic assessments (WIKUE, UU) has been formed. Industry (AVL, WHtech), SMEs (BIOS, HyGear), Universities (UU, TUD) as well as research organisations (IKTS, WIKUE) cooperate within this consortium.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the first 18 months of the 4-year project, the work focused on the development of the single plants components and the design, manufacturing and assembly of a first generation testing plant of the new technology. As an initial task, the operating conditions for the single plant components as well as the interfaces between them have been defined. Moreover, a detailed plant concept has been worked out. To achieve a high number of annual full load operation hours of the SOFC also at varying heat demands, a portion of the product gas from the gasifier is led through the gas cleaning unit to the SOFC system while the remaining product gas is combusted in a burner directly coupled with a boiler in order to gain a constant electricity production and a high heat production flexibility. Based on this approach the work regarding the single plant components was initialized.
Regarding the gasifier, the work started with the development of an integrated product gas extraction and heating unit through which the product gas is led towards the gas cleaning unit. Moreover, the gasifier was further developed in order to allow also the utilisation of biomass fuels with comparably low ash melting temperatures (such as agro-pellets) thus achieving a significantly enhanced fuel flexibility. Therefore, experimental studies at an adapted present model of the gasifier as well as comprehensive CFD (computational fluid dynamics) simulations have been performed. Based on the results of this work the new gasifier for the first testing plant has been constructed.
With respect to the gas cleaning unit, experimental work, process modelling and chemical equilibrium calculations were employed in order to develop the different reactors needed and to select appropriate sorbents for Cl and S-removal as well as catalysts for tar reforming. Also these tasks could be completed within the first project period and a first generation gas cleaning unit has been designed, manufactured and assembled.
Furthermore, a stationary SOFC system tailored to the gas composition of the cleaned and reformed product gas from the gasifier has been developed. Therefore, the stack module itself has been modified with respect to the product gas properties and the balance of plant components have been newly developed for integration into the whole plant concept. First validation tests with the stack module have revealed that the envisaged power (6 kWel for the first testing plant) can be achieved with product gas from the gasifier at the targeted electric efficiency.
Besides R&D on the main plant components also the overall control system has been developed and implemented. At the end of the reporting period, the assembly of the first generation testing plant took place. Test runs with this plant are foreseen for the coming months.
Besides these technical tasks, also a strong focus was put on economic, environmental and market related issues. The compilation of a comprehensive market study regarding the market potentials and future trends for micro-scale biomass CHP systems in Europe has been initialized in order to identify the most relevant future markets for the new technology. Preliminary techno-economic analyses have been performed in order to check the economic viability of the new technology and to define cost targets for the single plant components. Moreover, work on preliminary environmental, economic and societal assessments has been started.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

With its ambitious approach regarding the development of a first generation of a highly efficient and fuel-flexible micro-scale biomass CHP system the project shall at its end result in a significant step beyond the present state-of-the-art. For the first time a micro-CHP technology with almost zero emissions and an overall system efficiency close to 90% shall be made available. Therefore, the new technology shall have manifold impacts on European heat and power generation in terms of biomass fuel flexibility, biomass resource efficiency, power range flexibility as well as investment and operation costs.

Related information

Record Number: 195244 / Last updated on: 2017-02-23