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Following the 2005 Kyoto protocol, developed countries made commitments to reduce the emission of greenhouse gases, mostly by integrating renewable energy technologies into their power production systems. It is a more challenging procedure for third world countries, including Lebanon, that have limited means and potential to achieve such goals. This paper assesses the status of renewable energy systems in developing countries, and concentrates on the solar photovoltaic energy production due to its abundant availability in these countries relatively to other clean energy production methods. Comparisons of developing countries׳ achievements and goals each according to their economical, political and social considerations are conducted. Projects ranging from small scale standalone systems such as microgrids and minigrids to large scale energy production stations will be presented by dividing the countries into categories that share similar constraints and limitations in the integration of such installations. Furthermore, the paper analyzes the state of energy generation based on photovoltaic systems in Lebanon in contrast to other developing countries.

Following the 2005 Kyoto protocol, developed countries made commitments to reduce the emission of greenhouse gases, mostly by integrating renewable energy technologies into their power production systems. It is a more challenging procedure for third world countries, including Lebanon, that have limited means and potential to achieve such goals. This paper assesses the status of renewable energy systems in developing countries, and concentrates on the solar photovoltaic energy production due to its abundant availability in these countries relatively to other clean energy production methods. Comparisons of developing countries׳ achievements and goals each according to their economical, political and social considerations are conducted. Projects ranging from small scale standalone systems such as microgrids and minigrids to large scale energy production stations will be presented by dividing the countries into categories that share similar constraints and limitations in the integration of such installations. Furthermore, the paper analyzes the state of energy generation based on photovoltaic systems in Lebanon in contrast to other developing countries.

This paper deals with the problem of controlling hybrid energy storage system (HESS) for electric vehicle. The storage system consists of a fuel cell (FC), serving as the main power source, and a supercapacitor (SC), serving as an auxiliary power source. It also contains a power block for energy conversion consisting of a boost converter connected with the main source and a boost-buck converter connected with the auxiliary source. The converters share the same dc bus which is connected to the traction motor through an inverter. These power converters must be controlled in order to meet the following requirements: i) tight dc bus voltage regulation; ii) perfect tracking of SC current to its reference; iii) and asymptotic stability of the closed loop system. A nonlinear controller is developed, on the basis of the system nonlinear model, making use of Lyapunov stability design techniques. The latter accounts for the power converters large-signal dynamics as well as for the fuel-cell nonlinear characteristics. It is demonstrated using both a formal analysis and simulations that the developed controller meets all desired objectives.

This paper deals with the problem of controlling hybrid energy storage system (HESS) for electric vehicle. The storage system consists of a fuel cell (FC), serving as the main power source, and a supercapacitor (SC), serving as an auxiliary power source. It also contains a power block for energy conversion consisting of a boost converter connected with the main source and a boost-buck converter connected with the auxiliary source. The converters share the same dc bus which is connected to the traction motor through an inverter. These power converters must be controlled in order to meet the following requirements: i) tight dc bus voltage regulation; ii) perfect tracking of SC current to its reference; iii) and asymptotic stability of the closed loop system. A nonlinear controller is developed, on the basis of the system nonlinear model, making use of Lyapunov stability design techniques. The latter accounts for the power converters large-signal dynamics as well as for the fuel-cell nonlinear characteristics. It is demonstrated using both a formal analysis and simulations that the developed controller meets all desired objectives.

Enzymatic biofuel cells (EBFCs) provide a new strategy to enable direct biomass-to-electricity conversion, posing considerable demand on sequential enzymes. However, artificial blend of multi-enzyme systems often suffer biocatalytic inefficiency due to the rambling mixture of catalytic units. In an attempt to construct a high-performance starch/O2 EBFC, herein we prepared a starch-oxidizing bioanode based on displaying a sequential enzyme system of glucoamylase (GA) and glucose dehydrogenase (GDH) on E.coli cell surfaces in a precise way using cohesin-dockerin interactions. The enzyme stoichiometry was optimized, with GA&GDH (3:1)-E.coli exhibiting the highest catalytic reaction rate. The bioanode employed polymerized methylene blue (polyMB) to collect electrons from the oxidation of NADH into NAD+, which jointly oxidized starch together with co-displayed GA and GDH. The bioanode was oxygen-insensitive, which can be combined with a laccase based biocathode, resulting in a membranless starch/O2 EBFC in a non-compartmentalized configuration. The optimal EBFC exhibited an open-circuit voltage (OCV) of 0.74 V, a maximum power density of 30.1 ± 2.8 μW cm-2, and good operational stability.

Enzymatic biofuel cells (EBFCs) provide a new strategy to enable direct biomass-to-electricity conversion, posing considerable demand on sequential enzymes. However, artificial blend of multi-enzyme systems often suffer biocatalytic inefficiency due to the rambling mixture of catalytic units. In an attempt to construct a high-performance starch/O2 EBFC, herein we prepared a starch-oxidizing bioanode based on displaying a sequential enzyme system of glucoamylase (GA) and glucose dehydrogenase (GDH) on E.coli cell surfaces in a precise way using cohesin-dockerin interactions. The enzyme stoichiometry was optimized, with GA&GDH (3:1)-E.coli exhibiting the highest catalytic reaction rate. The bioanode employed polymerized methylene blue (polyMB) to collect electrons from the oxidation of NADH into NAD+, which jointly oxidized starch together with co-displayed GA and GDH. The bioanode was oxygen-insensitive, which can be combined with a laccase based biocathode, resulting in a membranless starch/O2 EBFC in a non-compartmentalized configuration. The optimal EBFC exhibited an open-circuit voltage (OCV) of 0.74 V, a maximum power density of 30.1 ± 2.8 μW cm-2, and good operational stability.

The Paris Agreement aims to limit global mean temperature rise this century well below 2 degrees Celsius above pre-industrial levels. This target has wide-ranging implications for Europe and its cities, which are the source of substantial proportions of greenhouse gas emissions. This paper reports the state of planning for climate change by collecting and analysing local climate mitigation and adaptation plans across 885 urban areas of the EU-28. A typology and analysis framework was developed that classifies local climate plans in terms of their spatial (alignment with local, national and international policy) and sectoral integration (alignment into existing local policy documents). We document local climate plans that we call type A1: non-compulsory by national law and not developed as part of international climate networks ; A2: compulsory by national law and not developed as part of international networks ; A3: plans developed as part of international networks. This most comprehensive analysis to date reveals that there is large diversity in the availability of local climate plans with most being available in Central and Northern European cities. Approximately 66% of EU cities have an A1, A2, or A3 mitigation plan, 26% an adaptation plan, 17% joint adaptation and mitigation plans, and about 30% lack any form of local climate plan (i.e. what we classify as A1, A2, A3 plans). Mitigation plans are more numerous than adaptation plans, but mitigation does not always precede adaptation. Our analysis reveals that city size, national legislation, and international networks can influence the development of local climate plans. We found that size does matter as about 70% of the cities above 1 million inhabitants have a comprehensive and stand-alone mitigation and/or an adaptation plan (A1 or A2). Countries with national climate legislation (A2), such as Denmark, France, Slovakia and the United Kingdom, are found to have nearly twice as many urban mitigation plans, and five times more likely to produce urban adaptation plans, than countries without such legislation. A1 and A2 mitigation plans are particularly numerous in Denmark, Poland, Germany, and Finland ; while A1 and A2 adaptation plans are prevalent in Denmark, Finland, UK and France. The integration of adaptation and mitigation is country-specific and can mainly be observed in countries where local climate plans are compulsory, especially in France and the UK. Finally, local climate plans of international climate networks (A3) are mostly found in the many countries where autonomous, i.e. A1 plans are less common. The findings reported here are of international importance as they will inform and support decision-making and thinking of stakeholders with similar experiences or developments at all levels and sectors in other regions around the world.