Scientific and Technological Objectives

This co-ordination action will simultaneously address the renewable energy industry, the micro-combined heat and power (micro-CHP) industry, and the renewable micro-CHP industry, which are very closely related and often one and the same.  There is currently research being conducted on a pan-European scale by research organisations, small industries, and major energy suppliers.

Due to such a diverse range of organisations and industries conducting largely independent studies in this field, and due to the economic, developmental, and environmental importance of the technology, it is essential that a network should be implemented to aid in the co-ordination of this research, and to help define technologies for future research.  This will have the benefit of maximising the European effort in this field of technology for the purpose of reducing environmental damage caused by energy production, and developing a sustainable energy system for future generations.

This project proposes to implement this strategy by fulfilling the following objectives:

• To stimulate and facilitate technology transfer between cutting-edge researchers and industries in the renewable micro-CHP industry, with the view of optimising its efficiency, cost-effectiveness, and market size, and hence boost the development of a sustainable energy infrastructure
• To evaluate technologies and research in the field of micro-CHP and renewable energy systems, with the aim of technological integration and the stimulation of research and development of new renewable micro-CHP technologies
• To facilitate the Community's aims for the agrarian sector in favour of the use of biofuels and climate gas mitigations, especially in the light of enlargement
• To disseminate the project’s results directly to target clients, and also to a wider audience

The primary deliverables of the project will be:

• A web site to facilitate project co-ordination and to provide a conduit for dissemination activity aimed at EU industries
• A permanent database mapping research activities in renewable micro-CHP in Europe and beyond
• Documented ‘State of the Art and Market Review’ and ‘Links between renewable energy systems and micro-CHP review’
• An ongoing network as an open co-operative international web for research, development, technology transfer and innovative applications, especially in favour of innovative small and medium-sized enterprises (SMEs)

International State of the Art

The co-generation of heat and power has been on the increase since 1988 and, in many countries (such as the Netherlands), is expected to rise to outputs as high as 8 GW.  There has been a growing trend in recent years, though, for the production of more efficient, smaller, personal units that are capable of supplying the energy needs of single industries and residences.  Although the manufacturing industry has traditionally been the largest user of this technology (at a value of 5 GW), smaller systems have been developed and installed in large buildings such as schools, offices, and blocks of flats. These units are called ‘mini-CHP’ and have an electrical output of around 5 kW.

The technology originally spearheading the trend towards smaller ‘mini-CHP’ systems was the four‑stroke single-cylinder gas engine, which has a capacity of 583 cm³, an electrical output of 5·5 kW, and can provide central heating systems with up to 12 kW of heat, recovered from the cooling water. This system, controlled and monitored by an on-board computer, can achieve efficiencies as high as 90%.

This gas engine mini-CHP system has been successfully implemented in offices, swimming pools, sports facilities, and residential units, such as blocks of flats and collections of houses.  However, due to the size and price of the system, it is not cost effective to install mini-CHP units in residences of fewer than fifteen homes.

With the advancement of technology (e.g. new mechanical drives, computer-designed heat exchangers) and materials (e.g. high temperature alloys, use of helium or hydrogen as working fluids), the rediscovery of the Stirling engine revolutionised the combined heat and power industry and is now spearheading the field of micro-CHP. The Stirling micro-CHP unit has a power output of around 800 W, which is at a level suitable for use by a single dwelling.  The high efficiency (up to 98%), low cost, versatility of fuel sources, and relatively simple design gives the system the potential to be implemented on a pan-European scale, and make a major contribution to the development of a sustainable energy infrastructure.

Other systems that are being researched with a high potential for micro-CHP are fuel cells, small gas engines, thermoelectric modules, the organic Rankine process, micro-turbines, internal combustion engines and heat pumps.  These systems, however, have not been developed to the same extent as the Stirling engine and it is an aim of this co-ordination action to help stimulate research and explore the full potential of each technology.

The Stirling engine (which has many different designs, including free piston, Stirling heat pumps, and linear motor design) is powered through external combustion.  This means that anything that produces heat can be used as a power source, e.g. wood, straw, petrol, kerosene, alcohol, propane, natural gas, methane, biogas, bio-oil, etc.  It also allows for non-carbon heat sources to be used, such as solar energy, geothermal energy or waste heat from industrial processes.

This diversity of fuel sources has allowed the Stirling engine to lead the way in renewable micro-CHP and allows the units to be used in all parts of the world, from highly developed areas to isolated rural communities, thereby contributing to the development of sustainable communities, not only at a European level, but also at an international level.

The first geothermal heat plants which so far have been used monovalently for heat supply in near-distant-grids are tentatively equipped with microturbines to expand efficiency by electricity  production.

One of the new technological paths is the application of organic Rankine (ORC) process to utilise low-temperature heat for power production.  The hot summer of 2003 stimulated growing interest for the air-conditioning of buildings to existing or future CHP generation, thus augmenting the normally limited use of heat in summertime for producing cold and extending the area of application both of CHP and near-surface geothermal.

In the next 10 years, much existing power plant capacity has to be replaced.  In Germany alone, up to 40 GW of installed electrical power will need to be substituted (99 hard coal and 46 lignite power plants are already older than 35 operational years).  Because of the very long time for return on investment for both nuclear and fossil-fuel power plants, this decision will essentially influence not only the kind of used power plant technology and its mix between centralised and decentralised plants but also the space to be granted to renewables.

Other advances in renewable fuel technology, such as biomass fermentation, pyrolysis, anaerobic digestion, hydrogen from biomass technologies, and other biomass conversion technologies, is aiding progress in other micro-CHP technologies.  For example, the quality, efficiency and cost-effectiveness of bio-oil and ethanol production have improved significantly during recent years, which, in turn, has renewed interest in internal combustion engines.  Thermal gasification techniques are also improving in efficiency and lowering in price, which might allow the more traditional gas power engines to become commercially viable as renewable micro-CHP systems.

Expected Network Innovations

The main innovations expected as a result of this project are:

• Improved co-ordination of European research in the field of renewable micro-CHP
• A state of the art review in the field of renewable micro-CHP, including a market analysis of the technologies reviewed in both present and predicted future market scenarios, aimed to improve the efficiency of future research and to optimise market penetration.
• A database of current research activities in the field of renewable micro-CHP, specifically designed to optimise technological comparison and evaluation of renewable micro-CHP technology.
• A report documenting the potential links between researched renewable energy systems and micro-CHP units, aimed at stimulating new research ideas throughout European industries and research centres. The report will include a technical and market analysis, to aid in the steering and efficiency of research, and hence improve European industrial competitiveness.
• Recommendations for suitable bioenergy and technical applications for the economically and socially crucial agrarian sector to facilitate favourable solutions for set-aside land, grant new profitable sources of income to farmers and the regional rural development

The global innovative aim for the network will be the emergence of new renewable micro-CHP technologies among European industries, and the development of a sustainable energy infrastructure, leading to sustainable communities, and the reduction of environmentally damaging emissions during power generation.