André Faaij

Exploration of the possibilities for production of Fischer Tropsch liquids and power via biomass gasification

This paper reviews the technical feasibility and economics of biomass integrated gasification–Fischer Tropsch (BIG-FT) processes in general, identifies most promising system configurations and identifies key R&D issues essential for the commercialisation of BIG-FT technology. The FT synthesis produces hydrocarbons of different length from a gas mixture of H2 and CO. The large hydrocarbons can be hydrocracked to form mainly diesel of excellent quality. The fraction of short hydrocarbons is used in a combined cycle with the remainder of the syngas. Overall LHV energy efficiencies,1 calculated with the flowsheet modelling tool Aspenplus, are 33–40% for atmospheric gasification systems and 42–50% for pressurised gasification systems. Investment costs of such systems () are MUS

Exploration of the ranges of the global potential of biomass for energy

280–450,2 depending on the system configuration. In the short term, production costs of FT-liquids will be about US

Global experience curves for wind farms

16/GJ. In the longer term, with large-scale production, higher CO conversion and higher C5+ selectivity in the FT process, production costs of FT-liquids could drop to US

Efficiency and economy of wood-fired biomass energy systems in relation to scale regarding heat and power generation using combustion and gasification technologies

9/GJ. These perspectives for this route and use of biomass-derived FT-fuels in the transport sector are promising. Research and development should be aimed at the development of large-scale (pressurised) biomass gasification-based systems and special attention must be given to the gas cleaning section.

Mitigation of global greenhouse gas emissions from waste: conclusions and strategies from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report. Working Group III (Mitigation):

Abstract This study explores the range of future world potential of biomass for energy. The focus has been put on the factors that influence the potential biomass availability for energy purposes rather than give exact numbers. Six biomass resource categories for energy are identified: energy crops on surplus cropland, energy crops on degraded land, agricultural residues, forest residues, animal manure and organic wastes. Furthermore, specific attention is paid to the competing biomass use for material. The analysis makes use of a wide variety of existing studies on all separate categories. The main conclusion of the study is that the range of the global potential of primary biomass (in about 50 years) is very broad quantified at 33−1135 EJy −1 . Energy crops from surplus agricultural land have the largest potential contribution (0– 988 EJy −1 ) . Crucial factors determining biomass availability for energy are: (1) The future demand for food, determined by the population growth and the future diet; (2) The type of food production systems that can be adopted world-wide over the next 50 years; (3) Productivity of forest and energy crops; (4) The (increased) use of bio-materials; (5) Availability of degraded land; (6) Competing land use types, e.g. surplus agricultural land used for reforestation. It is therefore not “a given” that biomass for energy can become available at a large-scale. Furthermore, it is shown that policies aiming for the energy supply from biomass should take the factors like food production system developments into account in comprehensive development schemes.

Bioenergy and climate change mitigation: an assessment

In order to forecast the technological development and cost of wind turbines and the production costs of wind electricity, frequent use is made of the so-called experience curve concept. Experience curves of wind turbines are generally based on data describing the development of national markets, which cause a number of problems when applied for global assessments. To analyze global wind energy price development more adequately, we compose a global experience curve. First, underlying factors for past and potential future price reductions of wind turbines are analyzed. Also possible implications and pitfalls when applying the experience curve methodology are assessed. Second, we present and discuss a new approach of establishing a global experience curve and thus a global progress ratio for the investment cost of wind farms. Results show that global progress ratios for wind farms may lie between 77% and 85% (with an average of 81%), which is significantly more optimistic than progress ratios applied in most current scenario studies and integrated assessment models. While the findings are based on a limited amount of data, they may indicate faster price reduction opportunities than so far assumed. With this global experience curve we aim to improve the reliability of describing the speed with which global costs of wind power may decline.

Techno-economic analysis of natural gas combined cycles with post-combustion CO2 absorption, including a detailed evaluation of the development potential

Policy objectives to increase biomass’ contribution to the energy supply in industrialised countries are quite ambitious, but biomass resources are rather limited and expensive in many situations. Therefore, an optimal utilisation of resources producing a maximum of energy at minimal costs is desirable. A wide variety of biomass conversion options with different performance characteristics exists. Also, the economic and energetic performance depends on many variables, such as costs of logistics, scaling effects and degree of heat utilisation to name a few. Therefore, system analysis is needed to identify optimal systems. In this study, different biomass energy systems are analysed regarding their energetic and economic performance related to fossil primary energy savings. The systems studied contain residual woody biomass, logistics, heat distribution and combustion or gasification units producing heat, power or CHP. The performance of systems is expressed as a function of scale. This is done by applying generic functions to describe plants’ efficiencies and specific investment costs and by expressing costs and energy use of logistic and heat distribution as a function of conversion unit capacities. Scale effects within biomass energy systems are significant. Up-scaling increases the relative primary energy savings of the studied systems within the scale range of 0– regarded, while costs per unit of primary energy savings decrease or have an optimum at medium scales. The relative primary energy savings lay between 0.53 and . With costs of 4– systems are not profitable under Dutch conditions with residual wood prices of while firing waste wood with zero costs at the plant gate renders profitable operation possible. Favourable in both economic and energy terms are BIG/CC plants.

Gasification of biomass wastes and residues for electricity production

Greenhouse gas (GHG) emissions from post-consumer waste and wastewater are a small contributor (about 3%) to total global anthropogenic GHG emissions. Emissions for 2004-2005 totalled 1.4 Gt CO2-eq year—1 relative to total emissions from all sectors of 49 Gt CO2-eq year— 1 [including carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and F-gases normalized according to their 100-year global warming potentials (GWP)]. The CH4 from landfills and wastewater collectively accounted for about 90% of waste sector emissions, or about 18% of global anthropogenic methane emissions (which were about 14% of the global total in 2004). Wastewater N2O and CO2 from the incineration of waste containing fossil carbon (plastics; synthetic textiles) are minor sources. Due to the wide range of mature technologies that can mitigate GHG emissions from waste and provide public health, environmental protection, and sustainable development co-benefits, existing waste management practices can provide effective mitigation of GHG emissions from this sector. Current mitigation technologies include landfill gas recovery, improved landfill practices, and engineered wastewater management. In addition, significant GHG generation is avoided through controlled composting, state-of-the-art incineration, and expanded sanitation coverage. Reduced waste generation and the exploitation of energy from waste (landfill gas, incineration, anaerobic digester biogas) produce an indirect reduction of GHG emissions through the conservation of raw materials, improved energy and resource efficiency, and fossil fuel avoidance. Flexible strategies and financial incentives can expand waste management options to achieve GHG mitigation goals; local technology decisions are influenced by a variety of factors such as waste quantity and characteristics, cost and financing issues, infrastructure requirements including available land area, collection and transport considerations, and regulatory constraints. Existing studies on mitigation potentials and costs for the waste sector tend to focus on landfill CH4 as the baseline. The commercial recovery of landfill CH4 as a source of renewable energy has been practised at full scale since 1975 and currently exceeds 105 Mt CO2 -eq year—1. Although landfill CH 4 emissions from developed countries have been largely stabilized, emissions from developing countries are increasing as more controlled (anaerobic) landfilling practices are implemented; these emissions could be reduced by accelerating the introduction of engineered gas recovery, increasing rates of waste minimization and recycling, and implementing alternative waste management strategies provided they are affordable, effective, and sustainable. Aided by Kyoto mechanisms such as the Clean Development Mechanism (CDM) and Joint Implementation (JI), the total global economic mitigation potential for reducing waste sector emissions in 2030 is estimated to be > 1000 Mt CO2-eq (or 70% of estimated emissions) at costs below 100 US

Biomass combustion for power generation

t— 1 CO2-eq year—1. An estimated 20—30% of projected emissions for 2030 can be reduced at negative cost and 30—50% at costs < 20 US

Replacing fossil based PET with biobased PEF; process analysis, energy and GHG balance

t—1 CO 2-eq year—1. As landfills produce CH 4 for several decades, incineration and composting are complementary mitigation measures to landfill gas recovery in the short- to medium-term — at the present time, there are > 130 Mt waste year— 1 incinerated at more than 600 plants. Current uncertainties with respect to emissions and mitigation potentials could be reduced by more consistent national definitions, coordinated international data collection, standardized data analysis, field validation of models, and consistent application of life-cycle assessment tools inclusive of fossil fuel offsets.