Background There are extensive and increasingly abandoned grasslands over large areas of Europe (e.g., approximately 1.5 million ha in Germany, 2.2 million ha in UK and 0.6 million ha in Estonia). Due to their rich diversity of both flora and fauna, these grasslands are listed among the targeted habitats within the Natura 2000 ecological framework. Once designated, conservation measures have to be taken in order to maintain the habitats and species in a "favourable conservation status" for which they are designated under EU Council Directives on the conservation of Natura habitats, on fauna and flora (92/43/EEC) and on the conservation of birds (2009/147/EC). Habitats may not be reduced in area, or altered in terms of structure and function, and their long-term maintenance is closely association with appropriate human use of the land. The University of Kassel has developed an approach to producing bio-energy from the harvest of mature and abandoned grasslands in protected Natura 2000 habitats that also helps to achieve conservation goals. It is thought to be especially suitable for extensive grasslands, but has yet to be tested on a large scale. Objectives The PROGRASS LIFE project tested the University of Kassel approach to producing bio-energy (electricity and solid fuel) on extensive areas of grassland for the first time. The objective was to scale up, demonstrate and implement the approach in extensive areas of abandoned grassland in European Natura 2000 habitats, in order to prove its feasibility and to provide evidence that the approach can protect these grassland biotopes through sustainable socio-economic development. Demonstrations were planned in each of the partner regions of Germany, Wales and Estonia. The project aimed to protect Natura 2000 reserves; secure the livelihoods of small farmers in marginal areas; compensate for the costs of conserving semi-natural grasslands; and increase awareness and acceptance for sustainable management of these biotopes. The ultimate goal, beyond the project duration, was the construction of full-scale PROGRASS energy units all over Europe to facilitate biomass and biogas productions from protected grassland sites. Results The PROGRASS project developed an integrated concept for the conservation of semi-natural grassland in Natura 2000 reserves in accordance with EU Directives on habitats and species. This was achieved through the extensive use of these areas for the Integrated Generation of Solid Fuel and Biogas from Biomass (IFBB). State-of-the-art technology was combined in a sustainable approach to gain bioenergy from a difficult grass substrate, which cannot be used with conventional technology. The project assessed the entire production chain, from harvesting, through analyses of silage and the fermentation process, to energy production; taking into account socio-economic and ecological aspects and the training of stakeholders. Inter-disciplinary studies were carried out at eighteen experimental sites in protected Natura 2000 habitats in each of the partner regions of Germany (Vogelsbergkreis), Wales (Ceredigion) and Estonia (Tartu). The sites chosen as locations for the mobile demonstration units provided representative samples of target grasslands, which covered most of the vegetation types found in Natura 2000 grassland habitats. This broad approach ensured that the PROGRASS concept was applicable across much of Europe, to prepare the ground for a European-wide transfer of the technology. PROGRASS plants can either be managed profitably as stand-alone operations or combined with a conventional biogas plant. Results showed that about 45% of the energy stored in biomass can be transformed into available heat. The power produced was used to meet the plant's electricity demands. Beyond that about 15% of the gross energy yield was used to cover internal heat demands, especially for drying. In combining the IFBB-system with a biogas plant that produces excess heat, the value of heat provision can be raised up to about 53% of the gross energy yield. An analysis of both the energy and greenhouse gas balances attained through different IFBB-related systems showed that the highest potential savings of fossil fuel and greenhouse gas emissions was obtained in an integrated system, whereby the IFBB-procedure is combined with an existing biogas or wastewater treatment plant. Furthermore, investment calculations showed that combining IFBB with a biogas plant resulted in improved economic efficiency of semi-natural grassland use. Productivity and quality of grassland biomass, and the dynamics of biodiversity, were assessed for different cutting regimes; standardised methods were produced for transforming the formerly unsuitable raw materials for energy recovery; and recommendations for regional stakeholders were made for securing small farmer livelihoods. Farmers were consulted regarding harvesting and conservation, while learning courses were organised for farmers, persons in relevant associations, decision-makers, local politicians and other stakeholders. Case studies were conducted to analyse the specific socio-economic conditions on a local scale, including seven micro-studies in new partner regions. It was concluded that PROGRASS plants could demonstrate a sustainable combination of nature protection and socioeconomic development for disadvantaged and marginal rural regions throughout Europe, with especially high potential for Eastern Europe. The project started the process of establishing a professional and enduring European PROGRASS Network. Further information on the project can be found in the project's layman report(see "Read more" section).