Supply chain and logistics issues of bio-energy production.

Waste biomass-to-energy supply chain management: A critical synthesis

Environmental assessment of marine fuels: liquefied natural gas, liquefied biogas, methanol and bio-methanol

Modeling of biomass-to-energy supply chain operations: Applications, challenges and research directions

The environmental impact of different land-use systems for energy, up to the farm or forest “gate”, has been quantified with Life Cycle Assessment (LCA). Four representative crops are considered: OilSeed Rape (OSR), Miscanthus , Short-Rotation Coppice (SRC) willow and forest residues. The focus of the LCA is on changes in Soil Organic Carbon (SOC) but energy use, emissions of GreenHouse Gases (GHGs), acidification and eutrophication are also considered. In addition to providing an indicator of soil quality, changes in SOC are shown to have a dominant effect on total GHG emissions. Miscanthus is the best land-use option for GHG emissions and soil quality as it sequesters C at a higher rate than the other crops, but this has to be weighed against other environmental impacts where Miscanthus performs worse, such as acidification and eutrophication. OSR shows the worst performance across all categories. Because forest residues are treated as a by-product, their environmental impacts are small in all categories. The analysis highlights the need for detailed site-specific modelling of SOC changes, and for consequential LCAs of the whole fuel cycle including transport and use.

Soil Organic Carbon Changes in the Cultivation of Energy Crops: Implications for GHG Balances and Soil Quality for Use in LCA

Biomass for energy conversion is usually considered as a local resource. With appropriate logistic systems, access to biomass can be improved over a large geographical area. In this study, life cycle inventory (LCI) has been used as a method to investigate the environmental load of selected bioenergy transport chains. As a case study, chains starting in Sweden and ending in Holland have been investigated. Biomass originates from tree sections or forest residues, the latter upgraded to bales or pellets. The study is concentrated on production of electricity, hot cooling water is considered as a loss. Electricity is, in the case study, produced from solid biomass in the importing country. Electricity can also be produced in the country of origin and exported via the transnational grid as transportation medium. The results show that emissions from long range transportation, 1200 km, performed with ships, is of minor importance compared to emissions from local bioenergy systems in a local market. In bioenergy systems the use of fuels and electricity for operating machines and transportation carriers requires a net energy input which amounts to typically 7‐9% of delivered electrical energy from the system. Emissions of key substances such as NOx, CO, S, hydrocarbons, and particles are low in a perspective of sustainability. Emissions of CO2 from biocombustion are considered to be zero since there is approximately no net contribution of carbon to the biosphere in an energy system based on biomass. The results indicate that biomass for energy can be transported from Scandinavia to Holland without losing its environmental benefits. 7 2000 Elsevier Science Ltd. All rights reserved.

Göran Forsberg

Papers

Biomass energy transport: Analysis of bioenergy transport chains using life cycle inventory method