Which is the best solar thermal collection technology for electricity generation in north-west India? Evaluation of options using the analytical hierarchy process

This study of concentrating solar thermal power generation sets out to evaluate the main existing collection technologies using the framework of the Analytical Hierarchy Process (AHP). It encompasses parabolic troughs, heliostat fields, linear Fresnel reflectors, parabolic dishes, compound parabolic concentrators and linear Fresnel lenses. These technologies are compared based on technical, economic and environmental criteria. Within these three categories, numerous sub-criteria are identified; similarly sub-alternatives are considered for each technology. A literature review, thermodynamic calculations and an expert workshop have been used to arrive at quantitative and qualitative assessments. The methodology is applied principally to a case study in Gujarat in north-west India, though case studies based on the Sahara Desert, Southern Spain and California are included for comparison. A sensitivity analysis is carried out for Gujarat. The study concludes that the linear Fresnel lens with a secondary compound parabolic collector, or the parabolic dish reflector, is the preferred technology for north-west India.

Techno-economic assessment and uncertainty analysis of thermochemical processes for second generation biofuels

Biomass-To-Liquid (BTL) is one of the most promising low carbon processes available to support the expanding transportation sector. This multi-step process produces hydrocarbon fuels from biomass, the so-called “second generation biofuels” that, unlike first generation biofuels, have the ability to make use of a wider range of biomass feedstock than just plant oils and sugar/starch components. A BTL process based on gasification has yet to be commercialized. This work focuses on the techno-economic feasibility of nine BTL plants. The scope was limited to hydrocarbon products as these can be readily incorporated and integrated into conventional markets and supply chains. The evaluated BTL systems were based on pressurised oxygen gasification of wood biomass or bio-oil and they were characterised by different fuel synthesis processes including: Fischer-Tropsch synthesis, the Methanol to Gasoline (MTG) process and the Topsoe Integrated Gasoline (TIGAS) synthesis. This was the first time that these three fuel synthesis technologies were compared in a single, consistent evaluation. The selected process concepts were modelled using the process simulation software IPSEpro to determine mass balances, energy balances and product distributions. For each BTL concept, a cost model was developed in MS Excel to estimate capital, operating and production costs. An uncertainty analysis based on the Monte Carlo statistical method, was also carried out to examine how the uncertainty in the input parameters of the cost model could affect the output (i.e. production cost) of the model. This was the first time that an uncertainty analysis was included in a published techno-economic assessment study of BTL systems. It was found that bio-oil gasification cannot currently compete with solid biomass gasification due to the lower efficiencies and higher costs associated with the additional thermal conversion step of fast pyrolysis. Fischer-Tropsch synthesis was the most promising fuel synthesis technology for commercial production of liquid hydrocarbon fuels since it achieved higher efficiencies and lower costs than TIGAS and MTG. None of the BTL systems were competitive with conventional fossil fuel plants. However, if government tax take was reduced by approximately 33% or a subsidy of £55/t dry biomass was available, transport biofuels could be competitive with conventional fuels. Large scale biofuel production may be possible in the long term through subsidies, fuels price rises and legislation.

Evaluation of vulnerability factors for cyclones : the case of Patuakhali, Bangladesh

Tropical cyclones are considered as the most severe natural disasters in Bangladesh; they cause extensive damage, create losses in the country׳s economy, and affect social settings. The impact of natural disasters has been further intensified due to various vulnerability factors within the Bangladeshi community such as low income; shortages of food; lack of assets such as land and permanent housing; dense population, illiteracy. This study evaluates the vulnerability factors for cyclones in the community based in the Patuakhali region of south western Bangladesh. The bottom-up research approach was adopted for the study, whereby the local community was consulted for their viewpoints by using focus group interviews and semi-structured interviews. Different community groups and social categories including both men and women, from different age groups and livelihoods, participated in the study. The study revealed how the community׳s vulnerability to cyclones has been further aggravated by socio-economic factors such as social status, political influences and economic conditions. The majority of the community in Patuakhali has been “knowingly” vulnerable to cyclone disaster as a result of the lack of alternatives especially in terms of their livelihood patterns. The vulnerability of women, due to their lack of authority, domestic work, and fear of exposure within the society was also highlighted. The study revealed how vulnerability factors are interlinked with each other making them further difficult to manage. This calls for multi-faceted disaster risk reduction strategies that targets vulnerability factors deriving from different origins and root causes.

Evaluation of vulnerability factors for cyclones:the case of Patuakhali, Bangladesh

Tropical cyclones are considered as the most severe natural disasters in Bangladesh; they cause extensive damage, create losses in the country[U+05F3]s economy, and affect social settings. The impact of natural disasters has been further intensified due to various vulnerability factors within the Bangladeshi community such as low income; shortages of food; lack of assets such as land and permanent housing; dense population, illiteracy. This study evaluates the vulnerability factors for cyclones in the community based in the Patuakhali region of south western Bangladesh. The bottom-up research approach was adopted for the study, whereby the local community was consulted for their viewpoints by using focus group interviews and semi-structured interviews. Different community groups and social categories including both men and women, from different age groups and livelihoods, participated in the study. The study revealed how the community[U+05F3]s vulnerability to cyclones has been further aggravated by socio-economic factors such as social status, political influences and economic conditions. The majority of the community in Patuakhali has been "knowingly" vulnerable to cyclone disaster as a result of the lack of alternatives especially in terms of their livelihood patterns. The vulnerability of women, due to their lack of authority, domestic work, and fear of exposure within the society was also highlighted. The study revealed how vulnerability factors are interlinked with each other making them further difficult to manage. This calls for multi-faceted disaster risk reduction strategies that targets vulnerability factors deriving from different origins and root causes. © 2014 Elsevier Ltd.

Economic efficiency of mobile latent heat storages

In a pilot project an optimized mobile latent heat storage based on a system available on the market has been tested at Fraunhofer Institute for Environmental, Safety and Energy Technology. Initially trials were conducted with the aim of optimizing the process of charging and discharging. A specifically constructed test rig at the incineration trials centre at the institute allowed charging and discharging procedures of the mobile latent heat storage with adjustable parameters. In addition an evaluation model was constructed to further optimize the heat exchanger systems. In conclusion the prototype of the mobile latent heat storage was tested in practical operation. The economic and technical feasibility of heat transportation was shown if not utilized waste heat is available. © 2014 The Authors.