Setting priorities for land management to mitigate climate change

<p>Abstract</p> <p>Background</p> <p>No consensus has been reached how to measure the effectiveness of climate change mitigation in the land-use sector and how to prioritize land use accordingly. We used the long-term cumulative and average sectorial C stocks in biomass, soil and products, C stock changes, the substitution of fossil energy and of energy-intensive products, and net present value (NPV) as evaluation criteria for the effectiveness of a hectare of productive land to mitigate climate change and produce economic returns. We evaluated land management options using real-life data of Thuringia, a region representative for central-western European conditions, and input from life cycle assessment, with a carbon-tracking model. We focused on solid biomass use for energy production.</p> <p>Results</p> <p>In forestry, the traditional timber production was most economically viable and most climate-friendly due to an assumed recycling rate of 80% of wood products for bioenergy. Intensification towards "pure bioenergy production" would reduce the average sectorial C stocks and the C substitution and would turn NPV negative. In the forest conservation (non-use) option, the sectorial C stocks increased by 52% against timber production, which was not compensated by foregone wood products and C substitution. Among the cropland options wheat for food with straw use for energy, whole cereals for energy, and short rotation coppice for bioenergy the latter was most climate-friendly. However, specific subsidies or incentives for perennials would be needed to favour this option.</p> <p>Conclusions</p> <p>When using the harvested products as materials prior to energy use there is no climate argument to support intensification by switching from sawn-wood timber production towards energy-wood in forestry systems. A legal framework would be needed to ensure that harvested products are first used for raw materials prior to energy use. Only an effective recycling of biomaterials frees land for long-term sustained C sequestration by conservation. Reuse cascades avoid additional emissions from shifting production or intensification.</p

Allocation in LCA of wood-based products experiences of cost action E9. Part II. Examples

Goal and Background The treatment of allocation in the descriptive LCA of wood-based products has been discussed for a long time and different solutions have been presented. In general, it is accepted that the influence of different allocation procedures on the results of LCA of wood-based products can be very significant. This paper is a result of the Cost Action E9 ‘Life cycle assessment of forestry and forest products’ and represents the experience of involved Cost E9 delegates. Objective Wood is a renewable material that can be used for wood products and energy production. Consistent methodological procedures are needed in order to correctly address the twofold nature of wood as a material and fuel, the multi-functional wood processing generating large quantities of co-products, and reuse or recycling of paper and wood. Ten different processes in LCAs of wood-based products are identified, where allocation questions can occur: forestry, sawmill, wood industry, pulp and paper industry, particle board industry, recycling of paper, recycling of wood-based boards, recycling of waste wood, combined heat and power production, landfill. Methodology Following ISO 14 041 a step-wise procedure for system boundary setting and allocation are outlined. As a first priority allocation should be avoided by system expansion, thus adding additional functions to the functional unit. Alternatively, the avoided-burden approach can be followed by subtracting substituted functions of wood that are additionally provided. If allocation cannot be avoided, some allocations methods from case studies are described. Conclusions The following conclusions for allocation in LCA of wood-based products are given. 1) Avoid allocation by expansion of system boundaries by combining material and energy aspects of wood, meaning a combination of LCA of wood products and of energy from wood with a functional unit for products and energy. 2) Substitute energy from wood with conventional energy in the LCA of wood products to get the functional unit of the wood product only, but identify the criteria for the substituted energy. 3) Substitution of wooden products with non-wooden products in LCA of bioenergy is not advisable, because the substitution criteria can be too complex. 4) If avoiding allocation is not possible, the reasons should be documented. 5) Different allocation procedures must be analysed and documented. In many cases, it seems necessary to make a sensitivity analysis of different allocation options for different environmental effects. It can also be useful to get the acceptance of the chosen allocation procedure by external experts. 6) Different allocation factors, e.g. mass or economic value, are allowed within the same LCA. 7) For allocation of forestry processes it is necessary to describe the main function of the forest where the raw material is taken out. In some cases different types or functions of forests must be considered and described. 8) Regarding the experiences from the examples, the following most practical allocation for some specific processes are identified: forestry: mass or volume; sawmill: mass or volume and proceeds; wood industry: mass and proceeds

Biorefinery systems – potential contributors to sustainable innovation

Sustainable biorefineries have a critical role to play in our common future. The need to provide more goods using renewable resources, combined with advances in science and technology, has provided a receptive environment for biorefinery systems development. Biorefineries offer the promise of using fewer non-renewable resources, reducing CO2 emissions, creating new employment, and spurring innovation using clean and efficient technologies. Lessons are being learned from the establishment of first-generation biofuel operations. The factors that are key to answering the question of biorefinery sustainability include: the type of feedstock, the conversion technologies and their respective conversion and energy efficiencies, the types of products (including coproducts) that are manufactured, and what products are substituted by the bioproducts. The BIOPOL review of eight existing biorefineries indicates that new efficient biorefineries can revitalize existing industries and promote regional development, especially in the R&D area. Establishment can be facilitated if existing facilities are used, if there is at least one product which is immediately marketable, and if supportive policies are in place. Economic, environmental, and social dimensions need to be evaluated in an integrated sustainability assessment. Sustainability principles, criteria, and indicators are emerging for bioenergy, biofuels, and bioproducts. Practical assessment methodologies, including data systems, are critical for both sustainable design and to assure consumers, investors, and governments that they are doing the ‘right thing’ by purchasing a certain bioproduct. If designed using lifecycle thinking, biorefineries can be profitable, socially responsible, and produce goods with less environmental impact than conventional products … and potentially even be restorative!

Towards a standard methodology for greenhouse gas balances of bioenergy systems in comparison with fossil energy systems

In this paper, which was prepared as part of IEA Bioenergy Task XV (“Greenhouse Gas Balances of Bioenergy Systems”), we outline a standard methodology for comparing the greenhouse gas balances of bioenergy systems with those of fossil energy systems. Emphasis is on a careful definition of system boundaries. The following issues are dealt with in detail: time interval analysed and changes of carbon stocks; reference energy systems; energy inputs required to produce, process and transport fuels; mass and energy losses along the entire fuel chain; energy embodied in facility infrastructure; distribution systems; cogeneration systems; by-products; waste wood and other biomass waste for energy; reference land use; and other environmental issues. For each of these areas recommendations are given on how analyses of greenhouse gas balances should be performed. In some cases we also point out alternative ways of doing the greenhouse gas accounting. Finally, the paper gives some recommendations on how bioenergy systems should be optimized from a greenhouse-gas-emissions point of view

The approach of life cycle sustainability assessment of biorefineries

A key driver for the necessary sustainable development is the implementation of the BioEconomy, which is based on renewable resources to satisfy its energy and material demand of our society. The broad spectrum of biomass resources offers great opportunities for a comprehensive product portfolio to satisfy the different needs of a BioEconomy. The concept of biorefining guarantees the resource and energy efficient use of biomass resources. The IEA Bioenergy Task 42 “Biorefining” has the following definition on biorefining: “Biorefining is the sustainable processing of biomass into a spectrum of bio-based products (food, feed, chemicals, and materials) and bioenergy (biofuels, power and/or heat)”. Currently many different biorefinery concepts are developed and already implemented which play a key role in establishing a BioEconomy. The purpose of the work is to develop implementing strategies of Biorefineries in the BioEconomy by applying and using a Life Cycle Sustainability Assessment Approach developed in cooperation with IEA Bioenergy Task 42 “Biorefining” and applied to an algae based biorefinery demonstrated in the EU project FUEL4ME. The aim is to provide facts, figures and framework conditions to maximise the overall sustainability benefits of an integrated material and energetic use of biomass. The scientific innovation is to integrate and combine these broad aspects of an overall assessment of a biorefinery in a common framework and the proof of its practical application to a biorefinery example. The framework covers 1) biorefinery classification, 2) assessment of the technologies and processes with their “Technology Readiness Level (TRL)” integrated in the “Biorefinery Complexity Index (BCI)”, 3) economic assessment based on Life Cycle Costing (LCC), 4) environmental effects based on Life Cycle Assessment (LCA), 5) social issues in a Social Life Cycle Assessment (sLCA) 6) overall Life Cycle Sustainability Assessment (LCSA), 7) identification of most attractive industry sectors (“Hot Spots”) for rolling out BioEconomy, 8) highlighting necessary R&D demand for commercialisation and 9) concluding on the possible future role of biorefining in a BioEconomy in a regional, national and international context. An innovative presentation in a compact format is developed - “Biorefinery Fact Sheet” - to present the assessment results. A set of broadly accepted sustainability indicators for comparison with conventional systems is identified: a) Environment: GHG emissions (t CO2-eq/a), primary energy demand (GJ/a), area demand (ha/a); b) Economy: production costs (€/a), revenues from products (€/a), value added (€/a), employment (persons/a), trade balance (€/a); c) Society: workers, consumers, local community. The whole concept is applied to a case study of using algal biomass to produce HVO-biofuels, PUFA and fertilizer, developed in the EU-demonstration project FUEL4ME for a future commercial scale. The results concentrated in the “Biorefinery Fact Sheet” for single biorefinery systems assist various stakeholders in finding their position on biorefining in a future biobased economy while minimising unexpected technical, economic and financial risks

Toward a common classification approach for biorefinery systems

This paper deals with a biorefinery classification approach developed within International Energy Agency (IEA) Bioenergy Task 42. Since production of transportation biofuels is seen as the driving force for future biorefinery developments, a selection of the most interesting transportation biofuels until 2020 is based on their characteristics to be mixed with gasoline, diesel and natural gas, reflecting the main advantage of using the already-existing infrastructure for easier market introduction. This classification approach relies on four main features: (1) platforms; (2) products; (3) feedstock; and (4) processes. The platforms are the most important feature in this classification approach: they are key intermediates between raw materials and final products, and can be used to link different biorefinery concepts. The adequate combination of these four features represents each individual biorefinery system. The combination of individual biorefinery systems, linked through their platforms, products or feedstocks, provides an overview of the most promising biorefinery systems in a classification network. According to the proposed approach, a biorefinery is described by a standard format as platform(s) - products - and feedstock(s). Processes can be added to the description, if further specification is required. Selected examples of biorefinery classification are provided; for example, (1) one platform (C6 sugars) biorefinery for bioethanol and animal feed from starch crops (corn); and (2) four platforms (lignin/syngas, C5/C6 sugars) biorefinery for synthetic liquid biofuels (Fischer-Tropsch diesel), bioethanol and animal feed from lignocellulosic crops (switchgrass). This classification approach is flexible as new subgroups can be added according to future developments in the biorefinery are