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This study is a product of the Africa Infrastructure Country Diagnostic (AICD), a project designed to expand the world's knowledge of physical infrastructure in Africa. The AICD provides a baseline against which future improvements in infrastructure services can be measured, making it possible to monitor the results achieved from donor support. It also offers a more solid empirical foundation for prioritizing investments and designing policy reforms in the infrastructure sectors in Africa. The book draws upon a number of background papers that were prepared by World Bank staff and consultants, under the auspices of the AICD. The main findings were synthesized in a flagship report titled Africa's infrastructure: A time for transformation, published in November 2009. Meant for policy makers, that report necessarily focused on the high-level conclusions. It attracted widespread media coverage feeding directly into discussions at the 2009 African union commission heads of state summit on infrastructure.

Information and communication technologies (ICTs) have been a remarkable success in Africa. Across the continent, the availability and quality of service have gone up and the cost has gone down. In just 10 years dating from the end of the 1990s mobile network coverage rose from 16 percent to 90 percent of the urban population; by 2009, rural coverage stood at just under 50 percent of the population. Although the performance of Africa's mobile networks over the past decade has been remarkable, the telecommunications sector in the rest of the world has also evolved rapidly. Many countries now regard broadband Internet as central to their long-term economic development strategies, and many companies realize that the use of ICT is the key to maintaining profitability. This book is about that challenge and others. Chapters two and three describe the recent history of the telecommunications market in Africa; they cover such issues as prices, access, the performance of the networks, and the regulatory reforms that have triggered much of the investment. This part of the book compares network performance across the region and tries to explain why some countries have moved so much more quickly than others in providing affordable telecommunications services. Chapter four explores the financial side of the telecommunications revolution in Africa and details how the massive investments have been financed and which companies have most influenced the sector. Chapter five deals with the future of the sector. The final chapter synthesizes the main chapters of the book and presents policy recommendations intended to drive the sector forward.

Rural households in the developing countries constitute the largest share of the biomass fuel consumption. It is also a major source of energy in the low income country. However, this energy consumption pattern varies from region to region. Different case studies on the biomass fuel consumption will certainly contribute to the understanding on the energy uses of a nation. The present study was conducted in the rural areas of the Meghna floodplain zone in Bangladesh, with a total of 80 sampled households, using the stratified random sampling technique through the semi-structured questionnaires from November 2008 through February 2009. Firewood, cowdung, leaves and twigs, branches, rice straw and rice husk were used as the biomass fuels mainly for the cooking purpose. Leaves and twigs were found as the dominant biomass fuel as 187 ± 25.69 (SE) kg month-1 household-1. The major source of biomass fuel collection was identified as the own homestead and agricultural lands, 74%. The households spent 14.56 ± 8.94 US$ month-1 household-1 for biomass fuels. The ratio of the total energy expenditure to the total income of the household was around 11%. But, the ratio of the biomass expenditure to the total energy expenditure of the households was 68%. Monthly income, land ownership and family size were found significantly influencing to the biomass energy expenditure. The study will be useful for the policy makers in the renewable energy, forestry and agriculture sector in Bangladesh.

This report demonstrates that a \"climate-smart\" energy strategy is possible for countries in the East Asia region, with support from the international community. In the past three decades, the East Asia region has experienced the fastest economic growth in the world, accompanied by rapid urbanization. As a consequence, energy consumption has more than tripled and is expected to further double over the next two decades. This remarkable growth and rapid urbanization have led to twin energy challenges in the region: improving environmental sustainability and enhancing energy security. The region has many of the world's most polluted cities, resulting from fossil fuel combustion. The region also contains some of the largest greenhouse gas emitters in the world, although their per capita and historical emissions are much below the levels of industrialized countries. Concerns with energy security have grown because of increased risks of price volatility and possible disruptions in supplies for oil and gas. To move the region to a sustainable energy path, the commitment of the respective governments and communities is essential. The governments will need energy-pricing reforms that no longer encourage the use of fossil fuels, and put in place regulations and incentives that improve energy efficiency and support low-carbon technologies. The governments also will need to ramp up research and development for new technologies to leapfrog to the clean energy revolution. The countries cannot move to a sustainable energy path alone. They will need the support of the international community. Substantial concessional financing is essential to motivate energy efficiency and low-carbon technology investments. Transfer of low-carbon technologies and institutional strengthening also will be needed.

Limiting fuel sulfur content (FSC) is a widely adopted approach for reducing ship emissions of sulfur dioxide (SO2) and particulate matter (PM), particularly in emission control areas (ECAs), but its impact on the emissions of volatile organic compounds (VOCs) is still not well understood. In this study, emissions from ships at berth in Guangzhou, southern China, were characterized before and after the implementation of the fuel switch policy (IFSP) with an FSC limit of 0.5 % in the Pearl River Delta ECA (ECA-PRD). After IFSP, the emission factors (EFs) of SO2 and PM2.5 for the coastal vessels decreased by 78 % and 56 % on average, respectively; however, the EFs of the VOCs were 1807±1746 mg kg−1, approximately 15 times that of 118±56.1 mg kg−1 before IFSP. This dramatic increase in the emissions of the VOCs might have been largely due to the replacement of high-sulfur residual fuel oil with low-sulfur diesel or heavy oils, which are typically richer in short-chain hydrocarbons. Moreover, reactive alkenes surpassed alkanes to become the dominant group among the VOCs, and low-carbon-number VOCs, such as ethylene, propene and isobutane, became the dominant species after IFSP. As a result of the largely elevated EFs of the reactive alkenes and aromatics after IFSP, the emitted VOCs per kilogram of fuel burned had nearly 29 times greater ozone formation potential (OFP) and approximately 2 times greater secondary organic aerosol formation potential (SOAFP) than those before IFSP. Unlike the coastal vessels, the river vessels in the region used diesel fuels consistently and were not affected by the fuel switch policy, but the EFs of their VOCs were 90 % greater than those of the coastal vessels after IFSP, with approximately 120 % greater fuel-based OFP and 70 %–140 % greater SOAFP. The results from this study suggest that while the fuel switch policy could effectively reduce SO2 and PM emissions, and thus help control PM2.5 pollution, it will also lead to greater emissions of reactive VOCs, which may threaten ozone pollution control in harbor cities. This change for coastal or ocean-going vessels, in addition to the large amounts of reactive VOCs from the river vessels, raises regulatory concerns for ship emissions of reactive VOCs.

In this review, a simple procedure that portends the open-pond growth of commercially viable diatoms is discussed. We examined a number of topics relevant to the production and harvesting of diatoms as well as topics concerning the production of bioproducts from diatoms. Among the former topics, we show that it is currently possible to continuously grow diatoms and control the presence of invasive species without chemical toxins at an average annual yield of 132 MT dry diatoms ha-1 over a period of almost 5 years, while maintaining the dominancy of the optimal diatom species on a seasonal basis. The dominant species varies during the year. The production of microalgae is essentially agriculture, but without the ability to control invasive species in the absence of herbicides and insecticides, pollution and production costs would be prohibitive. Among the latter topics are the discussions of whether it is better to produce lipids and then convert them to biofuels or maximize the production of diatom biomass and then convert it to biocrude products using, for example, hydrothermal processes. It is becoming increasingly evident that without massive public support, the commercial production of microalgal biofuels alone will remain elusive. While economically competitive production of biofuels from diatoms will be difficult, when priority is given to multiple high-value products, including wastewater treatment, and when biofuels are considered co-products in a systems approach to commercial production of diatoms, an economically competitive process will become more likely.

In order to identify and quantify key species associated with non-exhaust emissions and exhaust vehicular emissions, a large comprehensive dataset of particulate species has been obtained thanks to simultaneous near-road and urban background measurements coupled with detailed traffic counts and chassis dynamometer measurements of exhaust emissions of a few in-use vehicles well-represented in the French fleet. Elemental carbon, brake-wear metals (Cu, Fe, Sb, Sn, Mn), n-alkanes (C19-C26), light-molecular-weight polycyclic aromatic hydrocarbons (PAHs; pyrene, fluoranthene, anthracene) and two hopanes (17α21βnorhopane and 17α21βhopane) are strongly associated with the road traffic. Traffic-fleet emission factors have been determined for all of them and are consistent with most recent published equivalent data. When possible, light-duty- and heavy-duty-traffic emission factors are also determined. In the absence of significant non-combustion emissions, light-duty-traffic emissions are in good agreement with emissions from chassis dynamometer measurements. Since recent measurements in Europe including those from this study are consistent, ratios involving copper (Cu∕Fe and Cu∕Sn) could be used as brake-wear emissions tracers as long as brakes with Cu remain in use. Near the Grenoble ring road, where the traffic was largely dominated by diesel vehicles in 2011 (70 %), the OC∕EC ratio estimated for traffic emissions was around 0.4. Although the use of quantitative data for source apportionment studies is not straightforward for the identified organic molecular markers, their presence seems to well-characterize fresh traffic emissions.

Abstarct This study explores the use of microbial fuel cell (MFC) for wastewater treatment and energy production, focusing on enhancing electron generation. To encourage bacterial activity in removing metal ions from the inoculation source, coconut sugar and organic contaminants were used as dual substrates. With phenol degradation at 82.18% and removal efficiencies for Pb²⁺, Cd²⁺, and Cr³⁺ at 92.10%, 89.85%, and 90.60%, respectively, the study’s energy efficiency was 72.7 mW/m² within 21 days. Compared to the external resistance of 1000 Ω, the internal resistance was 514.39 Ω. On day 30, CV studies revealed maximum oxidation currents of 4.0 × 10⁻⁵ mA and peak reduction currents of -1.6 × 10⁻⁵ mA, suggesting increasing metal and phenol treatment. Lysinibacillus , Lysobacter , and Pseudoxanthomonas were found to be the dominating bacterial species at the anode biofilm, confirming the efficacy of this strategy via electrochemical and biological testing. The potential of coconut sugar in MFC applications was highlighted by its greater voltage generation when compared to other substrates. The research highlighted pH 7 and room temperature as optimal conditions while discussing processes and parameter optimization. The challenges of electron transportation are crucial for advancing MFC to a practical stage: hence, using waste materials for electrode production is a novel approach to address this challenge. However, there has been a thorough discussion of promising key challenges and potential future perspectives. Highlights Coconuts sugar is being used as an organic substrate in microbial fuel cells. Multiple water pollutants have been treated in the present study. Amazing maximum power density 72.7 mW/m² within 30 days has been achieved. Phenol degradation reached up to 82.18% with a high metal removal percentage (more than 90%). Lysinibacillus , Lysobacter and Pseudoxanthomonas are the most dominant species.

The oxidation of water to O 2 is a key challenge in the production of chemical fuels from electricity. Although several catalysts have been developed for this reaction, substantial challenges remain towards the ultimate goal of an efficient, inexpensive and robust electrocatalyst. Reported here is the first copper-based catalyst for electrolytic water oxidation. Copper–bipyridine–hydroxo complexes rapidly form in situ from simple commercially available copper salts and bipyridine at high pH. Cyclic voltammetry of these solutions at pH 11.8–13.3 shows large, irreversible currents, indicative of catalysis. The production of O 2 is demonstrated both electrochemically and with a fluorescence probe. Catalysis occurs at about 750 mV overpotential. Electrochemical, electron paramagnetic resonance and other studies indicate that the catalyst is a soluble molecular species, that the dominant species in the catalytically active solutions is (2,2′-bipyridine)Cu(OH) 2 and that this is among the most rapid homogeneous water-oxidation catalysts, with a turnover frequency of ~100 s −1 . Copper and bipyridine (bpy) self-assemble in aqueous solutions at high pH into an active electrocatalyst for the oxidation of water to O 2 , one of the great challenges in energy catalysis. These solutions contain primarily (bpy)Cu(OH) 2 , and are robust and active catalysts, albeit at high overpotentials.

An optimal energy mix of various renewable energy sources and storage devices is critical for a profitable and reliable hybrid microgrid system. This work proposes a hybrid optimization method to assess the optimal energy mix of wind, photovoltaic, and battery for a hybrid system development. This study considers the hybridization of a Non-dominant Sorting Genetic Algorithm II (NSGA II) and the Grey Wolf Optimizer (GWO). The objective function was formulated to simultaneously minimize the total energy cost and loss of power supply probability. A comparative study among the proposed hybrid optimization method, Non-dominant Sorting Genetic Algorithm II, and multi-objective Particle Swarm Optimization (PSO) was performed to examine the efficiency of the proposed optimization method. The analysis shows that the applied hybrid optimization method performs better than other multi-objective optimization algorithms alone in terms of convergence speed, reaching global minima, lower mean (for minimization objective), and a higher standard deviation. The analysis also reveals that by relaxing the loss of power supply probability from 0% to 4.7%, an additional cost reduction of approximately 12.12% can be achieved. The proposed method can provide improved flexibility to the stakeholders to select the optimum combination of generation mix from the offered solutions.