No abstract

We reported previously on the Biogasdoneright™ system for on‐farm biogas production. This innovative system employs sequential (year‐round) cropping to produce both food and energy from agricultural biomass, primarily cellulosic materials. This paper uses a marginal analysis approach to estimate the life cycle greenhouse gas emissions (GHGs) of electricity and biomethane produced by four currently operating Italian biogas plants that process various agricultural feedstocks, residues, and by‐products. The biogas is burned on‐farm to generate electricity that is then exported to the grid. The marginal lifecycle GHGs of this farm‐produced electricity range from ‐335 to 25 grams CO2 per kilowatt hour (kWh). By comparison, the marginal GHGs of electricity generated by fossil fuels in the European Union (EU) is 752 grams CO2 per kWh. The biogas might also be upgraded to produce pipeline‐quality biomethane, a direct substitute for natural gas. The marginal lifecycle GHGs of biomethane potentially produced from the Biogasdoneright™ plants range from 10 to ‐36 grams CO2 per megajoule (MJ) while the corresponding figure for a conventional biogas plant is 27 grams CO2 per MJ. Natural gas in the EU produces 72 grams CO2 per MJ and marginal fossil fuel in the EU generates 115 grams CO2 per MJ. Negative GHG emissions arise largely from avoided emissions of agricultural effluents and residues. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd

A group of over 600 Italian farmers organized as the Italian Biogas Consortium are redesigning their own farming systems to produce food and bioenergy in a nationwide farm‐level movement called Biogasdoneright™. This Feature demonstrates how it is possible to simultaneously increase the economic viability and stability of agriculture by reducing farm input costs and enabling farmers to produce food and fuel more sustainably. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

In this paper, we apply the principles of Biogasdoneright ® to agriculture in Sicily (Italy), or more generally to Mediterranean agriculture. We propose new potential crop rotation schemes using Sorghum spp. drip irrigated second harvest and Italian sainfoin (Hedysarum coronarium L.) between two cycles of durum wheat to produce biogas and perhaps biomethane subsequently under the Biogasdoneright system. The Biogasdoneright system is a new model for sustainable biogas production based on sequential cropping and integration with food production. In Sicily, as in other Mediterranean countries, sequential crops and some perennial crops such as Opuntia spp. might be cultivated in environmentally critical areas prone to erosion, desertifi cation, and fi res. Therefore, biogas produced according to the crop rotation schemes as illustrated in this paper avoids competition with food and feed crops, while offering to the Sicilian agricultural sector many agronomic, economic, environmental, and social benefi ts.

Current food production practices tend to damage and deplete soil, diminish biodiversity, and degrade water supplies. For agriculture to become environmentally sustainable and simultaneously increase food output for a growing world population, fundamental changes in agricultural production systems are required. Renewable energy can reduce greenhouse gases (GHGs) but we also need simple, low-cost approaches to remove atmospheric carbon and sequester it in stable forms. Recycling of digestate from the anaerobic digestion of agricultural and waste materials to soils can sequester atmospheric carbon and provide many other economic, social and environmental benefits. Biogasdoneright™ (BDR) is a set of practices that link biogas production with sustainable agriculture. The BDR approach to sustainable agriculture is being implemented on a large scale in Italy. In this paper, we examine the potential impact of implementing BDR in selected other countries. The biomethane potential in these countries, estimated conservatively, varies from about 10-30% of their current annual natural gas consumption. Biomethane from sequential (double) crops provides by far the greatest fraction of the biomethane potential. Double cropping also drives many of the environmental and economic benefits of BDR systems. Depending on where and how widely it is implemented, the production of biogas in BDR systems could have very significant national-level impacts. For example, sufficient biomethane could