Abstract: Diversifying the energy components of a country's transport sector is essential to guarantee the fuel supply to consumers and increase the market dynamics and competitiveness. Among the known alternative fuels, biogas is a renewable source and after upgrading to biomethane, it presents a similar composition to natural gas (>90% of CH4; 35-40 MJ m(-3)). In addition, it can be produced from a wide variety of biological resources and at different scales In this study, two scenarios have been developed that evaluate the use of liquefied biomethane (LBM) as a diesel replacement option in the freight sector of an area of 248,223 km(2) (equivalent to the area of the UK). Sugarcane vinasse (SVC) and Municipal Solid Waste (MSW) were the sole feedstocks for biogas production. The first scenario, non-restricted scenario (NRS), covered the entire territory while, the second scenario, restricted scenario (RS), includes only the area where gas pipelines are available. An economic assessment of the entire biogas value chain including, biogas production units, purification, transport and end-use was performed. The minimum selling price (MSP) of biomethane throughout the biogas chain was then estimated. LBM is estimated to be a cost-effective and affordable fuel choice compared to diesel. The technical potential of biogas production by the sugarcane mills and landfills of Sao Paulo state can replace up to half of the diesel consumed in the territory. The minimum distances and optimal locations methodology indicated the need for 120 liquefaction plants in the NRS, 35 injection points in the RS, and 7 refuelling stations to supply LBM throughout the state of Sao Paulo. The units for CO2 removal had the greatest influence on capital costs (similar to 60%) in both scenarios. Expenditure associated with the gas injection operation and its transport comprised more than 90% of the operating costs of the RS. Electricity purchasing represented the highest share of the operating costs at biogas purification (20%-30%) and biomethane liquefaction (65%-91%) units. Personnel costs are observed along the entire biogas chain, especially, in the biomethane transport step (40%), indicating an opportunity to generate wealth, jobs, and income. Despite our projections for the cost-effective and competitive supplies of LBM as a diesel replacement fuel, policy support measures such as a feed-in tariff, are likely to be necessary in order to overcome non-technical barriers and gain wider acceptability.

Abstract: Wood biomass is an important energy resource, which can contribute to reduce the dependence on fossil fuels. The research undertakes the microeconomic approach to estimate the technical availability and operational costs of woody biomass production with a higher level of precision than other models present in the literature, as it considers the entire supply chain of the sustainable management of natural forests. This study introduces a tool, which is applied to estimate supply curves and costs of wood biomass extraction from natural forests in the 7th Region of Chile. The simulation indicates that 531,015 tons/year of wood biomass is available in natural forests of the Region under study, with extraction costs ranging from 24.51 to 56.68 US$/ton, or an average total cost of 40.97 US$/ton. The parametric analysis revealed that the maximum admissible distance to the nearest transport route and the transportation costs are the two most influential variables in the estimation of wood biomass supply and cost. Reducing the admissible distance from 5 km to 1 km reduced the availability of biomass by 80%, while a variation of +/- 50% of transportation costs translated into +/- 18.3% variation of total extraction costs.
The proposed method can be used to identify the technical-economic potential of wood biomass from natural forests in any commune, province, region, or country; as it has the flexibility to allow tests with multiple scenarios and parameters depending on the specific characteristics of the area to be analysed. Essentially, the purpose of this tool is to serve the assessment processes of the identification of new wood biomass resources, allowing decision makers to increase the potential of sustainable and cost-effective woody biomass for heat and electricity generation, and at the same time reduce greenhouse gas emissions and the dependence on fossil fuels.

Abstract: The regional impact of climate change on heating and cooling demand is important to consider when designing optimal long-term energy policies. Several studies have addressed this issue, but either at a very aggregated level or without optimizing the whole energy system. The aims of this paper are to fill this gap in a generic way and to assess the impact of climate change on heating and cooling energy demands for residential and commercial sectors at the regional and nodal levels in the context of Chile's energy transition. We propose a methodology based on high resolution climate simulations for the Representative Concentration Pathways (RCP) RCP 2.6 and RCP 8.5 scenarios. First, a statistical analysis is performed to estimate the long-term trends of so-called heating and cooling degree-days and their impact on final regional energy demands. Then, demand pathways in the energy transition are assessed using a multi-sectoral energy planning model. Numerical experiments using data from Chile show an overall positive economic impact of climate change (limited to heating and cooling demands) for the energy system, with a significant decrease in heating demand compared to a limited increase in cooling requirements. For the RCP 8.5 scenario, cost reductions reach 2.1% of the total discounted system cost on the 2020-2050 period mainly due to a significant decrease of gas consumption for heating. This research highlights the importance for policymakers to consider climate change in efficient energy policies.