Exploratory Scenario Analyses Research Articles

Assessing the environmental impacts of wind-based hydrogen production in the Netherlands using ex-ante LCA and scenarios analysis

Two electrolysis technologies fed with renewable energy sources are promising for the production of CO2-free hydrogen and enabling the transition to a hydrogen society: Alkaline Electrolyte (AE) and Polymer Electrolyte Membrane (PEM). However, limited information exists on the potential environmental impacts of these promising sustainable innovations when operating on a large-scale. To fill this gap, the performance of AE and PEM systems is compared, using ex-ante Life Cycle Assessment (LCA), technology analysis and exploratory scenarios for which a refined methodology has been developed to study the effects of implementing large-scale sustainable hydrogen production systems. Ex-ante LCA allows modelling the environmental impacts of hydrogen production, exploratory scenario analysis allows modelling possible upscaling effects at potential future states of hydrogen production and use in vehicles in the Netherlands in 2050. A bridging tool for mapping the technological field has been created enabling the combination of quantitative LCAs with qualitative scenarios. This tool also enables diversity for exploring multiple sets of visions. The main results from the paper show, with an exception for the “ozone depletion” impact category, (1) that large-scale AE and PEM systems have similar environmental impacts with variations lower than 7% in all impact categories, (2) that the contribution of the electrolyser is limited to 10% of all impact categories results, and (3) that the origin of the electricity is the largest contributor to the environmental impact contributing to more than 90% in all impact categories, even when renewable energy sources are used. It is concluded that the methodology was applied successfully and provides a solid basis for an ex-ante assessment framework that can be applied to emerging technological systems.

The economic impact and cost-effectiveness of combined vector-control and dengue vaccination strategies in Thailand: results from a dynamic transmission model.

Background and aimsDengue fever is a major public health problem in tropical/subtropical regions. Prior economic analyses have predominantly evaluated either vaccination or vector-control programmes in isolation and do not really consider the incremental benefits and cost-effectiveness of mixed strategies and combination control. We estimated the cost-effectiveness of single and combined approaches in Thailand.MethodsThe impacts of different control interventions were analysed using a previously published mathematical model of dengue epidemiology and control incorporating seasonality, age structure, consecutive infection, cross protection, immune enhancement and combined vector-host transmission. An economic model was applied to simulation results to estimate the cost-effectiveness of 4 interventions and their various combinations (6 strategies): i) routine vaccination of 1-year olds; ii) chemical vector control strategies targeting adult and larval stages separately; iii) environmental management/ public health education and awareness [EM/ PHEA]). Payer and societal perspectives were considered. The health burden of dengue fever was assessed using disability-adjusted life-years (DALYs) lost. Costs and effects were assessed for 10 years. Costs were discounted at 3% annually and updated to 2013 United States Dollars. Incremental cost-effectiveness analysis was carried out after strategies were rank-ordered by cost, with results presented in a table of incremental analysis. Sensitivity and scenario analyses were undertaken; and the impact and cost-effectiveness of Wolbachia was evaluated in exploratory scenario analyses.ResultsFrom the payer and societal perspectives, 2 combination strategies were considered optimal, as all other control strategies were dominated. Vaccination plus adulticide plus EM/ PHEA was deemed cost-effective according to multiple cost-effectiveness criteria. From the societal perspective, incremental differences vs. adulticide and EM/ PHEA resulted in costs of $157.6 million and DALYs lost of 12,599, giving an expected ICER of $12,508 per DALY averted. Exploratory scenario analyses showed Wolbachia to be highly cost-effective ($343 per DALY averted) vs. other single control measures.ConclusionsOur model shows that individual interventions can be cost-effective, but that important epidemiological reductions and economic impacts are demonstrated when interventions are combined as part of an integrated approach to combating dengue fever. Exploratory scenario analyses demonstrated the potential epidemiological and cost-effective impact of Wolbachia when deployed at scale on a nationwide basis. Our findings were robust in the face of sensitivity analyses.

Whole Building Life Cycle Assessment of a Living Building

A whole building life cycle assessment (LCA) was performed on a Living Building, focusing on impacts from green building materials, a decentralized water system, a net-positive use phase, and the end-of-life of structural materials. The material processes used in this LCA were adjusted from standard to green by removing the use of toxic chemicals; results show carcinogenic impacts decreased by up to 96%. The septic system used for wastewater treatment contributes to 41% of the global warming potential [GWP, kg CO2eq (carbon dioxide equivalent)] over the building's assumed 100-year lifespan due to methane emissions. The on-site solar panels generate more electricity than the site demands, allowing for 44,000 kWh of green energy to be returned to the grid based on 1 year of performance. Lastly, an exploratory scenario analysis performed on multiple waste streams for structural materials shows that the GWP impacts for the end-of-life could vary from +14,000 to −10,500 kg CO2eq depending on the waste stream. The results of this LCA indicate that the case study building is net-zero energy and water, but not net-zero carbon.

A bricolage-style exploratory scenario analysis to manage uncertainty in socio-environmental systems modeling: investigating integrated water management options

Exploratory analysis, while useful in assessing the implications of model assumptions under large uncertainty, is considered at best a semi-structured activity. There is no algorithmic way for performing exploratory analysis and the existing canonical techniques have their own limitations. To overcome this, we advocate a bricolage-style exploratory scenario analysis, which can be crafted by pragmatically and strategically combining different methods and practices. Our argument is illustrated using a case study in integrated water management in the Murray-Darling Basin, Australia. Scenario ensembles are generated to investigate potential policy innovations, climate and crop market conditions, as well as the effects of uncertainties in model components and parameters. Visualizations, regression trees and marginal effect analyses are exploited to make sense of the ensemble of scenarios. The analysis includes identifying patterns within a scenario ensemble, by visualizing initial hypotheses that are informed by prior knowledge, as well as by visualizing new hypotheses based on identified influential variables. Context-specific relationships are explored by analyzing which values of drivers and management options influence outcomes. Synthesis is achieved by identifying context-specific solutions to consider as part of policy design. The process of analysis is cast as a process of finding patterns and formulating questions within the ensemble of scenarios that merit further examination, allowing end-users to make the decision as to what underlying assumptions should be accepted, and whether uncertainties have been sufficiently explored. This approach is especially advantageous when the precise intentions of management are still subject to deliberations. By describing the reasoning and steps behind a bricolage-style exploratory analysis, we hope to raise awareness of the value of sharing this kind of (common but not often documented) analysis process, and motivate further work to improve sharing of know-how about bricolage in practice.

Modeling Sustainability Scenarios in the Baltimore–Washington (DC) Region

Problem, research strategy, and findings: Planners today are confronted with unprecedented uncertainty in economic, political, and technological environments, especially at the regional scale. An increasingly common approach to addressing such uncertainty is exploratory scenario analysis. To provide new insights into the methods and utility of such analyses, we conducted a scenario analysis of the Baltimore (MD)–Washington (DC) region by engaging a technical advisory committee and exercising a loosely coupled suite of advanced transportation, land use, and environmental impact models. Our analysis suggests the future is indeed uncertain and may evolve into plausible but quite different alternative scenarios. Key drivers of these scenarios include fuel prices; the rate and form of technological change, especially in the transportation sector; and the restrictiveness of land use controls.Takeaway for practice: By developing exploratory scenario analyses and analyzing them using advanced computational models, planners can gain insights into how best to address uncertain development trends, such as how and to what degree planners can influence the adoption of electric and automated vehicles, how and where to guide development patterns through land use controls, and how best to respond to variation in the cost of energy, which could have dramatic impacts on the future sustainability of cities and regions. Although such scenario analyses cannot in most circumstances provide unambiguous robust or contingent policy prescriptions, they can provide important insights for raising public awareness and provide the foundation for further policy evaluation.

Exploratory scenario analysis for disaster risk reduction: Considering alternative pathways in disaster risk assessment

Disaster risk is a combination of natural hazards, along with society's exposure and vulnerability to them. Therefore, to ensure effective, long-term disaster risk reduction we must consider the dynamics of each of these components and how they change over extended periods due to population, economic and climatic drivers, as well as policy and individual decisions. This paper provides a methodology to capture these factors within exploratory scenarios designed to test the effectiveness of policy responses to reduce disaster losses. The scenarios developed and subsequent analysis of them combine knowledge and insight from stakeholders and experts, and make use of simulation modelling to enable scenarios with qualitative and quantitative elements to be integrated within risk assessment processes and contribute to strategic risk treatments. The methodology was applied to a case-study in Greater Adelaide, Australia, and used to assess how disaster risk for earthquakes, bushfire and coastal inundation changes from 2016 to 2050 under five exploratory scenarios for the future of the region. This analysis can be applied more broadly to consider how future risks impact on regional viability, and suitability for investment related to the need to gain a better understanding of governmental and organisational exposure to physical risks.

Cost-effectiveness analysis of lifestyle intervention in obese infertile women.

What is the cost-effectiveness of lifestyle intervention preceding infertility treatment in obese infertile women? Lifestyle intervention preceding infertility treatment as compared to prompt infertility treatment in obese infertile women is not a cost-effective strategy in terms of healthy live birth rate within 24 months after randomization, but is more likely to be cost-effective using a longer follow-up period and live birth rate as endpoint. In infertile couples, obesity decreases conception chances. We previously showed that lifestyle intervention prior to infertility treatment in obese infertile women did not increase the healthy singleton vaginal live birth rate at term, but increased natural conceptions, especially in anovulatory women. Cost-effectiveness analyses could provide relevant additional information to guide decisions regarding offering a lifestyle intervention to obese infertile women. The cost-effectiveness of lifestyle intervention preceding infertility treatment compared to prompt infertility treatment was evaluated based on data of a previous RCT, the LIFEstyle study. The primary outcome for effectiveness was the vaginal birth of a healthy singleton at term within 24 months after randomization (the healthy live birth rate). The economic evaluation was performed from a hospital perspective and included direct medical costs of the lifestyle intervention, infertility treatments, medication and pregnancy in the intervention and control group. In addition, we performed exploratory cost-effectiveness analyses of scenarios with additional effectiveness outcomes (overall live birth within 24 months and overall live birth conceived within 24 months) and of subgroups, i.e. of ovulatory and anovulatory women, women <36 years and ≥36 years of age and of completers of the lifestyle intervention. Bootstrap analyses were performed to assess the uncertainty surrounding cost-effectiveness. Infertile women with a BMI of ≥29 kg/m2 (no upper limit) were allocated to a 6-month lifestyle intervention programme preceding infertility treatment (intervention group, n = 290) or to prompt infertility treatment (control group, n = 287). After excluding women who withdrew informed consent or who were lost to follow-up we included 280 women in the intervention group and 284 women in the control group in the analysis. Total mean costs per woman in the intervention group within 24 months after randomization were €4324 (SD €4276) versus €5603 (SD €4632) in the control group (cost difference of -€1278, P < 0.05). Healthy live birth rates were 27 and 35% in the intervention group and the control group, respectively (effect difference of -8.1%, P < 0.05), resulting in an incremental cost-effectiveness ratio of €15 845 per additional percentage increase of the healthy live birth rate. Mean costs per healthy live birth event were €15 932 in the intervention group and €15 912 in the control group. Exploratory scenario analyses showed that after changing the effectiveness outcome to all live births conceived within 24 months, irrespective of delivery within or after 24 months, cost-effectiveness of the lifestyle intervention improved. Using this effectiveness outcome, the probability that lifestyle intervention preceding infertility treatment was cost-effective in anovulatory women was 40%, in completers of the lifestyle intervention 39%, and in women ≥36 years 29%. In contrast to the study protocol, we were not able to perform the analysis from a societal perspective. Besides the primary outcome of the LIFEstyle study, we performed exploratory analyses using outcomes observed at longer follow-up times and we evaluated subgroups of women; the trial was not powered on these additional outcomes or subgroup analyses. Cost-effectiveness of a lifestyle intervention is more likely for longer follow-up times, and with live births conceived within 24 months as the effectiveness outcome. This effect was most profound in anovulatory women, in completers of the lifestyle intervention and in women ≥36 years old. This result indicates that the follow-up period of lifestyle interventions in obese infertile women is important. The scenario analyses performed in this study suggest that offering and reimbursing lifestyle intervention programmes in certain patient categories may be cost-effective and it provides directions for future research in this field. The study was supported by a grant from ZonMw, the Dutch Organization for Health Research and Development (50-50110-96-518). The department of obstetrics and gynaecology of the UMCG received an unrestricted educational grant from Ferring pharmaceuticals BV, The Netherlands. B.W.J.M. is a consultant for ObsEva, Geneva. The LIFEstyle RCT was registered at the Dutch trial registry (NTR 1530). http://www.trialregister.nl/trialreg/admin/rctview.asp?TC = 1530.

Cost-Effectiveness Analysis of Obinutuzumab Versus Ofatumumab for Previously Untreated Chronic Lymphocytic Leukemia (CLL)

BackgroundTwo recently approved therapies for previously untreated chronic lymphocytic leukemia (CLL), (1) obinutuzumab (GA101) in combination with chlorambucil (G+Clb) and (2) ofatumumab in combination with Clb (O+Clb), have shown improved progression-free survival (PFS) versus Clb alone in two separate trials. However, their relative value has not been formally assessed. The objective of this study was to compare the cost-effectiveness of G+Clb versus O+Clb in previously untreated CLL patients, as well as conduct exploratory analyses versus other comparators.MethodsPatient outcomes were simulated using a 3-state Markov model that included PFS, progression, and death. PFS parameters for G+Clb were fitted to the observed G+Clb trial (CLL-11 study) data, and a network meta-analysis incorporating the results of the O+Clb (COMPLEMENT 1 study) was used to estimate the relative treatment effect of G+Clb compared to O+Clb (progression HR = 0.34). Patient populations in these two trials were similar. Drug utilization, dosing and adverse events were incorporated based on trial data, and costs were based on Medicare reimbursements and drug wholesale acquisition costs. One-way and probabilistic sensitivity analyses were conducted to assess the impact of data uncertainty on the results.In an exploratory scenario analyses, we used similar methodology to estimate the cost-effectiveness of G+Clb versus rituximab plus bendamustine (R+B, progression HR = 0.41). A meta-regression on age was used to adjust for the age difference among the patient populations and indirectly taking into account different levels of comorbidities.ResultsTreatment with G+Clb led to an increase of 0.83 life years and 0.79 quality-adjusted life years (QALYs) relative to O+Clb. The total cost of O+Clb was higher by $3600 per patient relative to G+Clb. Higher G+Clb drug, administration, and adverse event costs were largely offset by lower progression costs compared to O+Clb. The incremental cost per QALY gained with G+Clb vs. O+Clb was $4,500. Based on probabilistic sensitivity analyses, there was a 99% probability that G+Clb was cost-effective compared to O+Clb at a societal willingness-to-pay threshold of $100,000 per QALY saved. TableOutcomeG+ClbO+ClbDifferenceAverage life years5.744.910.83Average QALYs3.953.160.79Total drug cost$37,192$34,260$2,932Drug administration$1,977$991$985Supportive care$141$73$68Adverse events$9,542$2,660$6,882Cost of progression$46,861$54,147$(7,286)Average total cost$95,713$92,132$3,581In the exploratory scenario analysis, G+Clb was $37,700 less expensive than R+B, and led to an increase of 0.67 QALY.ConclusionsOur analysis suggests treatment with G+Clb compared to O+Clb is highly cost-effective based on indirect treatment comparison data. These results are driven by the improved PFS of G+Clb vs. O+Clb, as well as lower disease progression cost. Future direct comparisons of G+Clb versus other treatment options will further clarify the cost-effectiveness of G+Clb, and inform coverage and reimbursement policy decisions. DisclosuresReyes:Genentech: Employment, Equity Ownership. Off Label Use: Rituximab + Bendamustine in CLL. Gazauskas:Genentech: Consultancy. Becker:Roche: Employment. Moreno:Roche: Employment. Veenstra:Roche: Consultancy.

SAORES: a spatially explicit assessment and optimization tool for regional ecosystem services

The concept of ecosystem services (ES) has become mainstreamed in environmental planning and management recently, and with that various tools for quantifying ecosystem services have emerged. However, designing the tools for integrated assessment and optimization of multiple ES has become a challenging task. In order to promote the efficiency of ecosystem planning and management, we develop a spatial decision support tool named SAORES, which provides a platform for exploratory scenario analysis and optimal planning design, rather than ES assessment. SAORES is formed with four modules: the scenario development module, the integrated ecosystem service model base, the ecosystem service trade-off analysis module, and the multi-objective spatial optimization module based on NSGA-II. Using SAORES, we make a case study on the Yangou catchment of the Loess Plateau, China. Based on impact assessment of the Grain to green program (GTGP), we optimize the farmland retiring planning, involving multiple objectives which include the eco-compensation and the key ES. The integrated assessment shows that, the aim of the GTGP, the water and soil retention are prominent improved. Optimization for GTGP provides a series of optimal solutions, which are better than other single optimized solutions, and are twice the cost-effectiveness of the actual situation. SAORES, as a decision support tool, can improve the scenario analysis and multi-objective optimal planning design for ecosystem management and planning. The case study demonstrates the potential and effectiveness of SAORES and spatial multi-objective optimization model for ecosystem service management, especially in the Loess Plateau.

Prospects for Payments for Ecosystem Services in the Brazilian Pantanal: A Scenario Analysis

The present study investigates the prospects for a large-scale implementation of Payments for Ecosystem Services (PES) schemes in the Brazilian Pantanal wetland. Despite increasing environmental threats associated with development pressures and the growing interest of public and private organizations, no PES schemes are currently in place in the Pantanal. Through an exploratory scenario analysis, this article determines the prospects for PES in the area. The findings suggest that a large-scale implementation is unlikely, as this would require much higher levels of environmental awareness among local decision makers and low substitution rates of ecosystem services by technology. Furthermore, strong socioeconomic inequality between inhabitants of the Pantanal lowlands and wealthy farmers of the neighboring uplands means that potential suppliers of ecosystem services would face very high opportunity costs to participate in PES schemes. The research findings are also relevant to other environmentally sensitive regions experiencing rapid economic growth and weak environmental regulation.

Modeling of freshwater wetland management strategies for building the public awareness at local level in Bangladesh

Bangladesh has a large aerial extent of freshwater wetlands for her deltaic characteristics. In 1970, the total area of wetlands in Bangladesh is estimated to be 70000–80000 km2, approximately, i.e., 50 % of total national land area. In the recent years, most of these wetlands are being lost and degraded primarily because of flood control projects, irrigation and agricultural activities and others human interference. Unfortunately, over the last three decades in the name of wetland development, local habitats were not taken care of. In this paper, the stakeholder and scenario analyses are employed for measuring public views towards wetlands degradation in Bangladesh. Involvement of stakeholders helps reconcile their different conflicting interests in wetlands, hence creating a common understanding about the problem under study. An exploratory scenario analysis illustrates different themes fulfilled by the wetlands and their associated services in case study Chalan Beel. The Chalan Beel once covered an area of approximately 651,230 acres in 1967. Currently, the permanent flooded area of the Chalan Beel has been reduced to about 18,120 acres. The scenarios show that most of the wetlands in Bangladesh are converted into agricultural lands, settlements, roads, and highways. Aquatic plants and animals are lost and endangered due to human interference and natural disturbance. The government, policymakers and some private organizations are trying to design suitable policy for wetland management but they are not able to reach this goal. It is observed that the local and national policies are facing complexities to create an effective regime to set aside the wetlands management policy in Bangladesh. In this context, this paper proposed an Increased Public Awareness (IPA) policy model that could be pathways for both short and long-term solutions of wetlands degradation in developing nations like Bangladesh.

Linking conceptual and simulation models of the Cooum River: collaborative development of a GIS-based DSS for environmental management

The Cooum River is an extremely polluted stream that flows through Chennai, India. Past attempts to rehabilitate the river have focussed on physical interventions such as dredging. However, the problem continues to worsen. This research has borrowed techniques from adaptive management and soft systems methodology to apply an ecosystem approach to the problem. This involved participatory development of conceptual models of relevant systems that informed construction of a GIS-based DSS and environmental model. This paper addresses the link between conceptual models and the DSS. The process of problem identification, system conceptualization, development of the GIS database and DSS, and its use for exploratory scenario analysis was found to stimulate learning about the situation and promoted novel solutions to the problem.