Periodic Reporting for period 3 - D2Service (Design of 2 Technologies and Applications to Service)
Reporting period: 2018-09-01 to 2020-03-31
Fuel cells are a very efficient technology for generating electricity from natural gas or hydrogen, featuring high efficiencies and low pollutant and noise emissions. When used in micro-CHP units in building energy systems, a part of the waste heat from the electricity generation can be recovered and used to supply heat to the building. Another application is back-up power in case of power outages, where fuel cell-based systems efficiently and reliably provide clean electricity. Fuel cell appliances can thus make a valuable contribution to a cleaner energy supply.
As high-tech devices, these types of systems currently still require specially trained technicians for maintenance work and often non-standard components. In case of system failure, a specialist might have to travel a long distance to check and possibly repair a unit, which in turn is not producing energy during this time, leading to unnecessary high operational costs.
The project therefore focussed on the following aspects:
- System layout improvement for easier maintenance and components exchange, allowing for shorter service times.
- Individual component improvement and standardisation for easier replacement and increased durability, reducing service frequency.
- Remote monitoring improvement for earlier failure detection and avoidance of expensive service visits.
- Development of manual design guidelines to allow non-specialised technicians to perform routine service tasks.
A consortium of project partners from four European countries jointly worked on these aspects. Two different fuel-cell technologies – PEMFC and SOFC –were employed in different systems being improved in the project. In all addressed aspects concerning service, the project achieved significant improvements in term of reduction of service effort, service time, component and system durability, and service task complexity to enable non-specialised technicians to do elementary service work. The improvements have been tested and verified in a field trial on in total six systems.
In parallel, work was done on the improvement of important components. Coating methods of the cathode-side heat exchanger to reduce the chromium evaporation and subsequent stack CO-poisoning were investigated and successfully applied. New catalyst material for the Hydrodesulphurisation (HDS) unit with a strongly increased durability has been identified. Tests performed within the project duration indicate that a life time of 60,000 hours can be reached.
Developments of the SOFC micro-CHP system focused on redesigning the system layout to allow easier access for exchange and maintenance tasks and on improving lifetime and serviceability of individual components, such as stack, desulphurization, water treatment and air filter units.
To reduce maintenance efforts for micro-CHP systems as well as for back-up power units in remote areas, remote monitoring and diagnosis tools were improved, allowing for earlier failure detection and reduced service travel frequency.
As a result the periodic service intervals for micro-CHP systems have been increased by factor 2-4 and service cost has been reduced by more than 40%. In addition remote monitoring can reduce the service frequency by 20% and contribute to service cost reduction by up to 30%.
Guidelines for designing easily understandable manuals were developed and are available for download. Examples for describing component exchange tasks were designed using primarily graphical instructions to facilitate understanding and to avoid misunderstandings.
Easy understandable installation and service manuals enable local non-specialised technicians as well as selected service tasks can now be performed by the customer.
Several generations of the micro-CHP systems were evaluated in laboratory using realistic test scenarios to assess performance and reliability, and to identify possibilities for system improvements.
In a field trial with six systems in total, the project improvements could be refined and verified. The project developments will be exploited on various levels by the system manufacturers, energy service providers, component suppliers and research institutes involved in the project.
The durability of some key components has been improved, thereby reducing service frequency and replacement costs. By a special coating, chromium evaporation of the cathode-side heat exchanger and a subsequent stack poisoning is prevented. For the desulphurisation of the natural gas, a catalyst material has been identified with a potential life time 60,000 hours, thus eliminating the need of exchanging the component altogether.
Remote control and monitoring is a powerful technology to reduce the service costs further by avoiding costly on-site service. For both micro-CHP and back-up power systems, remote monitoring systems have been improved within the project, allowing for remote failure detection and mitigation. For the back-up power systems improved in the project, specialised algorithms allow for the estimation of the remaining-of-life of the stack and life prolongation by remotely controlled air starvation.
Overall, the project developments significantly decrease operating costs and thereby help to spread the distribution of efficient fuel cell technology in and beyond Europe. Manufacturers, service providers and customers are all expected to benefit from this alternative for low-emission, efficient and decentralized energy production being more widely available and significantly easier and more inexpensive to install service and maintain.