Abstract

Abstract
Increasing wildfire threats and costs escalate the complexity of forest fire management challenges, which is grounded in complex interactions between ecological, social, economic, and policy factors. It is immersed in this difficult context that decision-makers must settle on an investment mix within a portfolio of available options, subject to limited funds and under great uncertainty. We model intra-annual fire management as a problem of multistage capacity investment in a portfolio of management resources, enabling fuel treatments and fire preparedness. We consider wildfires as the demand, with uncertainty in the severity of the fire season and in the occurrence, time, place, and severity of specific fires. We focus our analysis on the influence of changes in the volatility of wildfires and in the costs of escaped wildfires, on the postponement of capacity investment along the year, on the optimal budget, and on the investment mix. Using a hypothetical test landscape, we verify that the value of postponement increases significantly for scenarios of increased uncertainty (higher volatility) and higher escape costs, as also does the optimal budget (although not proportionally to the changes in the escape costs). Additionally, the suppression/prevention budget ratio is highly sensitive to changes in escape costs, while it remains mostly insensitive to changes in volatility. Furthermore, we show the policy implications of these findings at operational (e.g., spatial solutions) and strategic levels (e.g., climate change). Exploring the impact of increasing escape costs in the optimal investment mix, we identified in our instances four qualitative system stages, which can be related to specific socioecological contexts and used as the basis for policy (re)design. In addition to questioning some popular myths, our results highlight the value of fuel treatments and the contextual nature of the optimal portfolio mix.

Abstract
In this paper we bring together a stochastic mixed integer programming model for transmission network expansion planning, incorporating portfolios of real options to address the evolution in time of uncertain parameters, with the adjusted generalized log-transformed model, to expand the number of correlated parameters that can be modeled. We apply these methods to evaluate the potential contribution of underwater transmission investments to increase renewables penetration in the Azores archipelago. The approach also includes expansion lead times, due to the large timespans involved in the construction of new transmission lines. Our analysis focuses on a set of the four closest islands in the archipelago, Pico, Faial, S. Jorge and Terceira, and shows that even though investments are delayed and the future network configuration varies according to the evolution of renewable generation scenarios, an investment in underwater transmission, if technically feasible, within the assumptions of our model, could in fact contribute to increase renewables penetration, by enabling islands with an excess in generation from renewable sources to supply other islands in a deficit situation.

Abstract
Across the world, several developing countries with recent wind energy (WE) diffusion have been demonstrating an interest in expanding WE generation quickly and expressively. In Brazil, this fast and remarkable WE diffusion process started in the past decade, facing a variety of barriers. This research proposes to reliably identify and analyse current barriers to the implementation of onshore wind farms in the country, aiming at informing other developing countries with the intention to expand WE utilization about potential barriers, as well as assisting the Brazilian WE sector in its efforts to keep growing sustainably. To achieve this research goal, 41 key stakeholders from the Brazilian WE sector were interviewed. Based on a content analysis of the interviews, twenty-four barriers where identified, three of which with particular relevance: poor transmission infrastructure, unattractive financial loans and unstable macroeconomic environment. The data collected suggests a serious risk that Brazil's WE sector stops growing if the recovery of its national economy, the reestablishment of regular energy auctions, the access to competitive credit, and improvements to the transmission system infrastructure keep being held back. In the face of this scenario, this study concludes by providing policy recommendations concerning the sustainability of the Brazilian WE sector.

Abstract
Investments in cross-border electricity interconnections are key for the integration of the European energy market. To analyze policy frameworks for these decisions, we model two settings for the expansion of transmission capacity between two regions, where the volume of investment is agreed upon through either Nash-Coase or Nash bargaining. For each setting we provide fair share cost allocation solutions, respectively with and without compensations. Each region has its own TSO, maximizing social welfare within its geography, and the markets are modeled with linear supply and demand curves, with trade enabled by the interconnection. The results of the application of the models to the Iberian market suggest their ability to estimate realistic values for the capacity of cross-border interconnection between two regions.

Abstract
Brazil has been failing to offer the most favorable conditions for the implementation of onshore wind farms, due to the presence of multiple barriers. However, the country has observed a fast and expressive wind energy (WE) diffusion (the installed WE capacity grew 37 times in the last decade). Furthermore, its onshore wind farms have reached impressive capacity factors (with productivity levels much higher than the average around the world) and a very low levelized cost of electricity. This study aims at identifying how wind developers plan onshore wind farms to overcome existing barriers. Based on forty-one interviews with relevant stakeholders of the Brazilian WE sector, the study identified efforts targeted at overcoming twenty-four previously identified barriers. Although most barriers may be overcome directly through developer initiatives, addressing higher level barriers, namely an unstable macroeconomic environment, a poor transmission infrastructure, and inadequate access to capital, depends on government actions.