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Reporting period: 2018-03-01 to 2019-08-31

FLEXCHX is a three-year project (2018-2021), which develops a flexible and integrated hybrid process combining electrolysis of water with gasification of biomass and catalytic liquefaction. The project is aimed at creating a method for managing the seasonal mismatch between solar energy supply and the demand of heat and power that is highly pronounced particularly in northern and central Europe. The state-of-the-art Combined Heat and Power (CHP) technologies have become under severe financial stress in a number of European markets characterized by a rapid addition of VRE (variable renewable energy) capacity and stagnating electricity demand. Consequently, many new thermal generators are currently designed to produce only hot water for heating purposes instead of CHP (this is also the case in Finland where CHP has been the common standard so far). As a result, there is a clear need for new flexible district heating and combined heat and power production solutions in Europe that can maintain economic feasibility under increasing VRE penetration. The FLEXCHX concept constitutes a complete rethinking of how combined heat and power should be produced in variable renewable energy-dominated power grids, and how the use of excess solar and wind energy can be combined with effective use of biomass residues. The FLEXCHX process can be integrated to various combined heat and power production systems, both industrial CHPs and communal district heating units. In the summer season, renewable fuels are produced from biomass and hydrogen; the hydrogen is produced from water via electrolysis that is driven by low-cost excess electricity from the grid. In the dark winter season, the plant is operated only with biomass in order to maximize the production of the much needed heat, electricity and FT hydrocarbons. Most of the invested plant components are in full use throughout the year, only the electrolysis unit is operated seasonally.

The overall goal of FLEXCHX is to develop a flexible energy production process that can be operated in the future European energy mix throughout the year with high efficiency and low cost. The specific project objectives are:
1. To develop an integrated production concept for heat, power and transport fuels utilizing biomass/waste and excess renewable electricity
2. To develop and validate (to TRL5) the key enabling technologies required for realizing the FLEXCHX process
3. To design and evaluate an optimal introduction of the intermediate hydrocarbon feed (FT wax) from several distributed biomass gasification/electrolysis units to a centralized large-scale refinery in order to meet the target production cost of renewable transport fuels 80-100 €/MWh (< 80-100 cents/l) of drop-in liquid fuel (such as diesel, jet fuel, gasoline).
4. To produce a techno-economic map of Europe for the specific CHP applications, where implementation of the FLEXCHX technology gives the best economics along the value chain of renewable heating and cooling
5. To present a road map for follow-on demonstration and industrial deployment taking into consideration regional socio-economic-political landscapes.
To fulfill the ambitious goal and objectives of FLEXCHX, the project is organized in nine work packages: WP1 Coordination and Management; WP2 Concept development; WP3 Gasification and raw gas cleaning; WP4 Reforming and final syngas cleaning; WP5 Flexible FT synthesis; WP6 Validation of the key enabling technologies; WP7 Integration of FT products to refineries; WP8 Techno-economic & environmental assessment of the process concepts, and WP9 Dissemination and Exploitation. WP3, WP4 and WP5 are technical development work packages for the key enabling technologies of the project. During the first half of the project, WP3 has modified an existing fixed bed gasification pilot plant of VTT into a pressurized staged fixed gasifier followed by hot filtration and catalytic reforming units. This process can be flexibly operated with mixtures of oxygen, air, steam and carbon dioxide as the gasification agents simulating different operating modes of the FLEXCHX process. The plant was successfully taken into operation and two one-week-long gasification tests were realised with a total of 130 hours of operation under gasification including 12 measured set points. The raw gas was filtered from particulates in a hot filter unit consisting of 12 candle filters. Filter unit could be operated with stable pressure drop and the goal of total particulate removal was achieved. The filtered gasification gas was led into the catalytic reformer, which is developed in WP4. In the reformer, tars and light hydrocarbon gases were effectively reformed and the synthesis gas approached the equilibrium of homogeneous water gas shift reaction. In WP4, the reformer process concept is developed by VTT, while Johson Matthey is developing and testing highly efficient and impurity tolerant catalysts for this process. In WP5, Ineratec has used their laboratory and bench-scale test facilities for studying the performance of their Fischer-Tropsch synthesis technology with various gas compositions representing different operating modes of the FLEXCHX process. WP6 will validate the operation of the whole gasification, gas cleaning and synthesis operation during the second half of the project.

WP2, WP7 and WP8 are supporting the experimental development and validation activities. In WP2, three reviews have been made. The status and outlook of elecrolysis technologies were reviewed by DLR, the biomass feedstock potential in the target countries was studied by Enerstena, VTT and LEI. LEI together with Helen studied the CHP markets in Lithuania and Finland and made a preliminary design on how to integrate the FLEXCHX process to selected CHP plants and systems. In WP7, Neste Engineering Solutions NES made a study on the market outlook of biofuels and examined how the FT products produced at distributed FLEXCHX plants can be introduced to the processes of oil refining industry. In WP8, DLR has made a simulation model for the whole FLEXCHX process and studied by detailed modelling the performances of the individual process steps.
FLEXCHX concept will progress beyond the present state-of-the-art in several areas as summarized below:
• The proposed way of integrating low-cost variable electricity with biomass gasification captures this otherwise curtailed energy with minimal losses and simultaneously converts biomass carbon to valuable and urgently needed transport fuels
• Tri-generation of power, heat and fuel intermediates allows flexible operation of production units that follow market signals for these energy products.
• The main novel approach of FLEXCHX is the method for operating the plant flexibly under different operating modes, either maximizing the production of transport fuel intermediate (solar season) or maximizing the overall efficiency to power, heat and fuel component (heating season).
• FT wax is an ideal intermediate product that can be collected from several primary plants to centralized refineries, where high-quality fuels are produced for aviation, maritime and heavy duty road transport.
• The new process for flexible production of heat, power and fuels at the target scale of 5-50 MW (where most of the CHP potential is) is based on the development of highly innovative new technologies
Experimental approach of FLEXCHX project
Operation of the FLEXCHX process in summer season
Operation of the FLEXCHX process in dark heating season