Escalating Energy Demand Research Articles

Enzymatic delignification and saccharification of Bambusa bambos for biobutanol production

Conversion of lignocellulosic biomass to energy is a transformational approach for addressing the escalating energy demand and environmental concerns along with waste management. In the present study, bamboo rich in holocellulose content (cellulose, 42.47 ± 2.3% (w/w) and hemicellulose, 20.10 ± 1.0% (w/w)) was used for biobutanol production. A concoction of laccases (as ligninolytic enzyme) and saccharolytic enzymes (cellulases and xylanases) were used in a single vessel for reducing sugar production from bamboo. Bamboo hydrolysate had glucose, xylose and cellobiose as reducing sugars which were used by Clostridium beijerinckii (ATCC 55025-E604) for ABE (acetone, butanol, and ethanol) production. C. beijerinckii utilized glucose, xylose and cellobiose efficiently and produced ABE when commercial sugars were studied individually. Process parameters studies showed that ABE yield was 0.35 g/g-sugar at 37 °C, pH 6.5, inoculum volume 12% v/v, inoculum age 18 h and fermentation time 60 h. Further optimization of C/N ratio, methyl viologen and CaCO3 Led to increase in the yield of butanol by 30.39%, w/v while the overall ABE yield was increased by 17.79%, w/v as compared to control (without use of C/N ratio, methyl viologen and CaCO3). The enzymes used for these studies are of high titer and produced indigenously utilizing cheaper substrates such as agroresidues under solid state fermentation. Moreover, overall process effectiveness is promising and attractive because of higher conversion efficiency, eco-friendliness and biodegradable nature.

Standards? Whose standards?

ABSTRACTBuilding standards, regulations and labelling schemes are instruments for reducing energy demand and carbon emissions, linking policy ambitions to market-based responses. In practice, their effects are complicated. In this paper we show how ‘market standards’ in the office sector are fostering escalating energy demand and favouring building designs increasingly disconnected from changing user needs. In ‘black boxing’ ideas about needs, standards powerfully and dangerously stabilize, and often escalate, concepts of ‘normal’ provision. Far from being neutral, standards are operating amid competing interests and ambitions in the market place. Processes of black-boxing, locking-in, ratcheting, reification, circulation and disconnection (the ‘dark sides’ of standards in action) are investigated to explore how they might be avoided. The paper provides insight into the role that market standards play in energy demand in the non-domestic (office) sector, through an examination of ten case studies of speculative office developments in London.

Hemodynamic and Metabolic Assessment of Neonates With Punctate White Matter Lesions Using Phase-Contrast MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI.

The brain's hemodynamic and metabolism of punctate white matter lesions (PWML) is poorly understood due to a scarcity of non-invasive imaging techniques. The aim of this study was to apply new MRI techniques to quantify cerebral metabolic rate of oxygen (CMRO2), global cerebral blood flow (CBF), oxygen saturation fractions in venous blood (Yv) and oxygen extraction fraction (OEF) in neonates with PWML, for better understanding of the pathophysiology of PWML. Fifty-one newborns were recruited continuously, including 23 neonatal patients with PWML and 28 normal control neonates. Phase-contrast (PC) MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI were performed for the measurement of CBF and Yv. OEF and CMRO2 were calculated from the CBF and Yv values. The total maturation score (TMS) was assessed for each neonate on standard T1, 2-weighted images to evaluate cerebral maturation. The CMRO2, CBF, Yv, and OEF values were compared between groups, and their associations with age and TMS were evaluated. Significant differences between PWML group and control group were found in CMRO2 (P = 0.020), CBF (P = 0.027), Yv (P = 0.012), OEF (P = 0.018). After age/maturation is accounted for, Yv and OEF showed significant dependence on the groups (P < 0.05). Newborns with PWML had lower OEF and higher Yv. CMRO2, CBF and brain volume were correlated with age (P < 0.001) and TMS (P < 0.05). It is feasible to use non-invasive MRI methods to measure cerebral oxygen supply and consumption in neonates with PWML. Newborns with PWML have lower oxygen consumption. Yv and OEF may be helpful for the diagnosis of PWML. The positive correlation between CBF and TMS, and between CMRO2 and TMS suggested that as myelination progresses, the blood supply and oxygen metabolism in the brain increase to meet the escalating energy demand.

Multiyear Load Growth Based Techno-Financial Evaluation of a Microgrid for an Academic Institution

An escalating energy demand can be seen especially in developing and fast-growing economies such as India. Conventional energy resources meet most of the energy demand. The alarming issue of global warming and the dependency on fossil fuels to meet the energy demand has motivated the use of clean energy sources. In this context, the educational institutions with high electricity consumption in India have been planning to opt for locally available renewable energy sources to meet their electricity demand. Even one of the most crucial issues in such academic institutions is the food waste management. Most of the institutes, give up their food wastage to piggeries which are directly fed to animals or discarded or dumped irrationally. In this paper, an optimal microgrid solution using locally available energy resources for a real physical location considering its real time-power demand is proposed. Various scenarios and different combinations of energy sources, such as solar photovoltaic, food waste based biogas plant, and a diesel generator as backup have been considered along with batteries as storage in off-grid and grid-connected systems. Hybrid optimization of multiple electric renewables (HOMER) PRO software package is utilized for detailed technical and financial analysis with a multiyear growth approach to determine the optimal energy system, which is unlikely observed in literature so far. The detailed analysis results illustrate that photovoltaic contributes most of the electricity being generated in all the scenarios. The renewable fraction is comparatively high in the off-grid system in the range of 92% to 100% as compared with 63% to 80% in grid-connected systems. The results obtained also show that levelized cost of electricity is low in case of grid-connected systems varying between 0.18 Indian National Rupee (INR)/kWh to 1.39 INR/kWh in contrast to 11.96 INR/kWh to 18.47 INR/kWh for off-grid systems.

The benefits of the transition from fossil fuel to solar energy in Libya: A street lighting system case study

The Libyan economy is dominated by the oil and the gas industry which are considered as the primary energy sources for the generating power plants. With the increased energy demands in the near future, Libya will be forced to burn more oil and gas. This, in turn will result in reducing the country revenue, threatening the economy and increasing the CO2 emission. This triggers the alarm for Libya to an urgent plan to diversify the energy sources through using sustainable energy. The sun showers Libya every day by a huge amount of sunshine, especially during the peaks in the summer days. Recently, the country has been struggling to satisfy its escalating energy demands. The residential and street lighting loads constitute more than 50% of the electricity demands in Libya. Street lighting consumes more than 3.996 TW h, which is around one fifth of the energy demands in Libya. Energy conservation and transition from fossil fuel to renewable energy could have significant profit on the energy sector in Libya. For example, Libya is still relying on the old-fashioned, inefficient and unsustainable street lighting systems. Replacing the old technology lighting systems with up-to-date solar powered lighting system can achieve energy saving and sustainability. In this paper, improving the energy situation in Libya through replacing the high pressure sodium street lighting systems with solar powered LED street lighting systems is investigated. A four km road is chosen as a case study. Four alternatives are analyzed; grid-powered high pressure sodium lamp street lighting system, grid-powered LED lamp street lighting system, stand-alone solar powered LED street lighting system and grid-connected solar powered LED street lighting system. The four options are compared in terms of the capital cost, maintenance cost, total cost, fuel cost and the CO2 emission. Replacing the high pressure sodium lamp system with LED lamp system saves 75% of energy and reduces the CO2 emission by 75%. The stand-alone solar powered LED lighting system cuts the CO2 emission, saves the fuel and is economically feasible. Furthermore, improvement is attained if the solar powered lighting system is connected to the grid where the excess energy is fed to the grid. The two solar powered options are economically feasible and sustainable.

Process optimization for cultivation and oil accumulation in an oleaginous yeast Rhodosporidium toruloides A29

Biodiesel is a renewable and environment friendly energy source, which is a potential alternative to petro-diesel. In the present study, mass production of microbial lipid by the yeast strain Rhodosporidium toruloides A29 was studied for biodiesel production. Realizing the importance of microbial lipids as a potential source for biodiesel, the strain was evaluated for higher biomass production using statistical modelling approach, which resulted in a lipid yield of 0.436g/g cell dry weight. This high lipid content was achieved using RSM optimized medium containing 2.5g/L of yeast extract, 2.75g/L of NaNO3, 0.5g/L of MgSO4 and 75g/L of glucose. The production of R. toruloides was successfully scaled up in a 30L bioreactor. In the reactor, lipid yield increased to 0.535g/g CDW leading to a 22-fold increase in oil content after scale up. Fatty acid characterization of the oil by GC revealed that R. toruloides A29 lipids consist of 34.59% saturated fatty acids, 46.49% monosaturated fatty acids and the rest polyunsaturated fatty acid. Transesterification of the extracted yeast oil revealed that the FAME (biodiesel) formed was similar in composition to the biodiesel produced from vegetable oil. The physico-chemical properties of the transesterified SCO were in range of the biodiesel standard specifications. Thus, this makes the microbial lipids obtained from R. toruloides A29 as potential alternative oil for sustainable production of biodiesel to meet the escalating energy demands.

Real-time optimal water allocation for daily hydropower generation from the Vanderkloof dam, South Africa

The adverse effects of power shortages resulting from escalating energy demands, due to rapid global urbanization and industrial developments, have driven efforts worldwide in search for improved techniques for sustainable reservoir operations and optimization for hydropower generation. Recent studies have shown that, combining accurate reservoir inflow forecasting procedures with efficient optimization techniques can produce more efficient and balanced solutions, for operation of multipurpose reservoir systems to improve on the economy of hydropower production. This study presents the coupling of a data driven artificial neural network (ANN) model and a novel combined Pareto multi-objective differential evolution (CPMDE), for hydrological simulation and multi-objective numerical optimization of hydropower production, from the Vanderkloof dam in real-time. Results from the application of the real-time strategy, indicate a significant improvement in performance over the current practice. Therefore, the hybrid ANN-CPMDE real-time reservoir operation model suggested herein provides a low cost solution methodology, suitable for sustainable operation of the Vanderkloof reservoir in South Africa.

Safety assessment of limestone-based engineering structures to be partially flooded by dam water: A case study from northeastern Turkey

Turkey has been faced with an escalating energy demand and recurring droughts within the last few decades. The construction of the BAGISTAS 1 Hydroelectric Power Plant Dam, one of the dams constructed in order to solve these problems, resulted in the partial submersion of a number of pre-existing railway bridges and retaining walls of the Divrigi-Ilic-Erzincan Railway System (NE Turkey). Before the accumulation of dam water, the structural safety of these 86-year-old infrastructures, which were constructed using carbonate rocks, were investigated under saturated conditions. The maximum uniaxial compressive strength (UCS) losses under saturated conditions, after the application of freezing-thawing, and after wetting-drying cycles, were determined. For the mortar samples obtained from a drill core, the wet-to-dry UCS ratio was determined to be 0.82, suggesting a high durability performance. The natural filling material, which was used behind the retaining structures and as the railway embankment, was classified as the selective filling material, representing the best conditions for a filling material. The samples representing the retaining wall and filling materials had very high slake durability indexes, showing that they are very durable under the effect of water. The closed-form analysis for partially submerged retaining walls indicated that the structures are safe against overturning and have permissible internal wall stresses under operational conditions. In addition, the structural safety assessment of a masonry bridge was investigated using 3D Finite Element Modeling (FEM) under the designed train and expected earthquake loads, in both dry and partly immersed conditions. The results of the study showed that the strength reduction of masonry in saturated conditions, under the raised waters of the newly constructed dam, has an insignificant effect on the submerged sections and does not pose any danger to the overall structural performance.

NATURAL VENTILATION IN OLD ISLAMIC HOUSES THE STUDY OF COURTYARD IN OLD CAIRO CASE STUDY:

Cairo; the capital of Egypt, is a rich architectural environment with long history extending over 70,000 years. The rich history is still educating and informing knowledge in all fields of science. An important part of this history is the Islamic era and its vibrant architecture. This research studies the architecture of houses in old Cairo and focuses mainly on their courtyards. Courtyards in old houses served many purposes; social, religious and environmental factors. Egypt has been confronted with an escalating energy demand due to the gradual rise in the use of mechanical ventilation associated with loss in natural ventilation design in houses. This paper aims at learning from the past to achieve a sustainable built environment by understanding the necessity of passive ventilation strategies and how courtyards inform it. This is achieved through inductive methods such as literature review represented in the first part and analytical method through the application of passive ventilation in an old courtyard Islamic house.

Luminescence of Eu3+ in a Mullite-Type Host Material Bi2Ga2Al2O9

The escalating energy demand coupled with limited conventional energy resources led to a widening gap between supply and demand, making it inevitable to look for novel energy efficient technologies. Solid state lighting is one of the promising areas where a significant amount of energy consumed can be conserved without compromising on the sophistications of conventional lighting. Solid state lighting kindled the interest of researchers owing to their impressive energy efficiency, longer life time, greater reliability, eco-friendly nature and the reasonable ease of fabricating the white light emitting diodes (WLEDs). Typically blue light emitting chip in combination with yellow light emitting phosphor1, Y3Al5O12:Ce3+ (YAG:Ce3+) have been used to produce the white light. However, the obtained white light has poor light quality and low color rendering index (CRI >80), due to lack of red component in the obtained white light spectrum. Tricolor phosphors (red, green and blue) in combination with near ultra violet (NUV) emitting source (InGaN chip) were considered to be an alternative to get better lighting properties and the generated white light by this technique has similarity to sun light and a good CRI value2 , 3. The commercially used red phosphor Y2O2S:Eu3+ is sensitive towards moisture and decomposed under high temperature which is harmful to the environment. Nitrides, CaAlSiN3:Eu2+ can be used as a substitute but its preparation needs greater care and highly controlled preparation conditions. Therefore, the red phosphors with thermal, chemical stability and high luminous intensity became an essential need for lighting industries. Recently, mullite and mullite-type ceramics have attracted attention because of their interesting optical properties4, high thermal and chemical stability5. In this context, we report Eu3+ activated mullite-type Bi(1-x)2Ga2Al2O9:xEu3+ (x = 0.00, 0.025, 0.05, 0.10, 0.20 and 0.30) solid solution which were prepared by simple solid state method. The prepared samples were characterized by x-ray diffraction and luminescence properties were measured under near UV and blue light excitation. The europium dopped Bi2Ga2Al2O9 (BGAO) showed characteristic excitation peaks between 250 nm and 500 nm. The chromaticity coordinates (0.61, 0.37) calculated under blue light excitation for 20% Eu3+ doped BGAO, located in orange-red region of chromaticity graph. The coordinates were close to the reference red phosphors and the results indicate that it have potential application in the field of lighting and displays under blue LED excitation.

Evaluation of solid fuel char briquettes from human waste.

The developing world faces dual crises of escalating energy demand and lack of urban sanitation infrastructure that pose significant burdens on the environment. This article presents results of a study evaluating the feasibility of using human feces-derived char as a solid fuel for heating and cooking and a potential way to address both crises. The study determined the energy content and the elemental composition of chars pyrolyzed at 300, 450, and 750 °C. Fecal chars made at 300 °C were found to be similar in energy content to wood chars and bituminous coal, having a heating value of 25.6 ± 0.08 MJ/kg, while fecal chars made at 750 °C had an energy content of 13.8 ± 0.48 MJ/kg. The higher heating values of the studied chars were evaluated using their elemental composition and a published predictive model; results found good agreement between the measured and predicted values. Fecal chars made at low temperatures were briquetted with molasses/lime and starch binders. Briquettes made with 10% starch had an average impact resistance index of 79 and a higher heating value of 25 MJ/kg. These values are comparable to those of commercial charcoal briquettes, making fecal char briquettes a potential substitute that also contributes to the preservation of the environment.

Soil microbial communities under model biofuel cropping systems in southern Wisconsin, USA: Impact of crop species and soil properties

Biofuel-induced landscape change will have an enormous impact on terrestrial ecosystems in the near future due to globally escalating energy demands, but investigations into the biological properties of soil under potential biofuel crops have not been well documented. The soil microbiota plays a significant role in ecosystem services and especially their regulation of carbon and nutrient cycles. To improve our knowledge about the structure of soil microbial community and the factors that influence it, we analyzed microbial lipids and various soil physicochemical factors under model biofuel cropping systems of corn, switchgrass and mixed prairie in southern Wisconsin, USA. Principal component analysis of lipid biomarkers from soil microbial communities indicated that there were consistent differences among the crop species. Microbial biomass was significantly lower in corn than prairie soils, with switchgrass intermediate to these systems. An increase in fungi to bacteria ratio was coinciding with a net growth in fungal biomass when converting conventionally managed corn system to perennial systems, which indicates the microbial community change could be affected by the creation or expansion of niches for certain functional groups, rather than rebalancing of competitive interactions among these groups. The soil microbial community structure under corn was distinct from the perennial systems with markers indicative of greater in situ stress in annual corn sites and a reduced proportional abundance of arbuscular mycorrhizal fungi and an increased of gram-positive bacteria. Redundancy analysis (RDA) using 21 lipid biomarkers concurrently with 17 physicochemical indices showed that these properties correlated with different subsets of the microbial communities. We conclude that the cropping system shifted the microbial community composition at this regional scale, which may also affect the microbial processes associated with these differing communities. This may be significant when scaled up from regional to national, continental or global scales.

Enhanced Oil Recovery - An Overview

Nearly 2.0 × 1012 barrels (0.3 × 1012 m3 ) of conventional oil and 5.0 × 1012 barrels (0.8 × 1012 m3 ) of heavy oil will remain in reservoirs worldwide after conventional recovery methods have been exhausted. Much of this oil would be recovered by Enhanced Oil Recovery (EOR) methods, which are part of the general scheme of Improved Oil Recovery (IOR). The choice of the method and the expected recovery depends on many considerations, economic as well as technological. This paper examines the EOR methods that have been tested in the field. Some of these have been commercially successful, while others are largely of academic interest. The reasons for the same are discussed. The paper examines thermal and non-thermal oil recovery methods. These are presented in a balanced fashion, with regard to commercial success in the field. Only a few recovery methods have been commercially successful, such as steam injection based processes in heavy oils and tar sands (if the reservoir offers favourable conditions for such applications) and miscible carbon dioxide for light oil reservoirs. Other recovery methods have been tested, and even produced incremental oil, but they have inherent limitations. The current EOR technologies are presented in a proper perspective, pointing out the technical reasons for the lack of success. Methods for improving oil recovery, in particular those concerned with lowering the interstitial oil saturation, have received a great deal of attention both in the laboratory and in the field. From the vast amount of literature on the subject, one gets the impression that it is relatively simple to increase oil recovery beyond secondary (assuming that the reservoir lends itself to primary and secondary recovery). It is shown that this is not the case. Many reservoirs suitable for steam injection and carbon dioxide have already been exploited and are approaching maturity. Other EOR methods suffer from limitations that have little to do with economics. Recovering incremental oil is complex and costly, and has been successful only for a few processes under exacting conditions. Nevertheless, EOR will continue to have an important place in oil production, in view of the escalating energy demand and the tight supply. It is suggested that much research is needed to develop technologies for recovering over two-thirds of the oil that will remain unrecovered in reservoirs. Key references are indicated.

An adaptive model for smart grid evaluation using deep learning approaches

This study addresses the escalating energy demands faced by global industries, exerting pressure on power grids to maintain equilibrium between supply and demand. Smart grids play a pivotal role in achieving this balance by facilitating bidirectional energy flow between end users and utilities. Unlike traditional grids, smart grids incorporate advanced sensors and controls to mitigate peak loads and balance overall energy consumption. The proposed work introduces an innovative deep learning strategy utilizing bi-directional Long Short Term Memory (b-LSTM) and advanced decomposition algorithms for processing and analyzing smart grid sensor data. The application of b-LSTM and higher-order decomposition in the analysis of time-series data results in a reduction of Mean Absolute Percentage Error (MAPE) and Minimal Root Mean Square (RMSE). Experimental outcomes, compared with current methodologies, demonstrate the model’s superior performance, particularly evident in a case study focusing on hourly PV cell energy patterns. The findings underscore the efficacy of the proposed model in providing more accurate predictions, thereby contributing to enhanced management of power grid challenges.