Harnessing overlapped temperature-salinity gradient in solar-driven interfacial seawater evaporation for efficient steam and electricity generation

Solar-driven interfacial water evaporation(SIWE)offers a superb way to leverage concentrated solar heat to minimize energy dissipation during seawater desalination.It also engenders overlapped temperaturesalinity gradient(TSG)between water-air interface and adjacent seawater,affording opportunities of harnessing electricity.However,the efficiency of conventional SIWE technologies is limited by significant challenges,including salt passivation to hinder evaporation and difficulties in exploiting overlapped TSG simultaneously.Herein,we report self-sustaining hybrid SIWE for not only sustainable seawater desalination but also efficient electricity generation from TSG.It enables spontaneous circulation of salt flux upon seawater evaporation,inducing a self-cleaning evaporative interface without salt passivation for stable steam generation.Meanwhile,this design enables spatial separation and simultaneous utilization of overlapped TSG to enhance electricity generation.These benefits render a remarkable efficiency of90.8%in solar energy utilization,manifesting in co-generation of solar steam at a fast rate of 2.01 kg m^(-2)-h^(-1)and electricity power of 1.91 W m^(-2)with high voltage.Directly interfacing the hybrid SIWE with seawater electrolyzer constructs a system for water-electricity-hydrogen co-generation without external electricity supply.It produces hydrogen at a rapid rate of 1.29 L h^(-1)m^(-2)and freshwater with 22 times lower Na+concentration than the World Health Organization(WHO)threshold.

Electricity generation during wastewater treatment by a microbial fuel cell coupled with constructed wetland

A membrane-less constructed wetland microbial fuel cell （CW-MFC） is constructed and operated under continuous flow with a hydraulic retention time （HRT） of 2 d. Fed with glucose, the CW-MFC generates a stable current density of over 2 A/m3 with a resistor of 1 kΩ and has a chemical oxygen demand （COD） removal efficiency of more than 90% after the startup of 2 to 3 d. A series of systems with the electrode spacings of 10, 20, 30 and 40 cm are compared. It is found that the container with the electrode spacing of 20 cm gains the highest voltage of 560 mV, the highest power density of 0. 149 W/m 3, and the highest Coulombic efficiency of 0.313%. It also has the highest COD removal efficiency of 94. 9%. In addition, the dissolved oxygen （DO） concentrations are observed as the lowest level in the middle of all the CW-MFC reactors. The results show that the more COD is removed, the greater power is generated, and the relatively higher Coulombic efficiency will be achieved. The present study indicates that the CW-MFC process can be used as a cost-effective and environmentally friendly wastewater treatment with simultaneous power generation.

Environmental damage costs from fossil electricity generation in China, 2000~2003

Electricity consumption increases rapidly with the rapid development of China. The environmental damage costs of electricity generation are very important for both policy analysis and the proper management of the environment. A method was developed in this work to estimate gross environmental damage costs according to emission inventory and environmental cost factors, and to extend the costs from provincial to national level with population density. In this paper, sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter less than 10 μm in diameter (PM10), and carbon dioxide (CO2) from fossil fired power plants over 6000 kW were selected as index pollutants to quantify the environmental costs of damages on human health and global warming. With the new developed method, environmental damage costs, caused by 3 types of fired power plants in 30 provinces and 6 economic sectors during the years 2000 to 2003, were evaluated and analyzed. It can be seen that the calculated total national environmental damage costs of electricity have rapidly increased from 94930.87×106 USD in 2000 to about 141041.39×106 USD in 2003, with an average annual growth rate of 14.11%. Environmental damage costs of SO2, NOx, PM10, and CO2 are 69475.69×106, 30079.29×106, 28931.84×106, and 12554.57×106 USD and account for 49.26%, 21.33%, 20.51%, and 8.90% of total environmental costs in fossil electricity generation, respectively. With regard to regional distribution, external costs caused by fossil electricity generation are mainly concentrated in the more populated and industrialized areas of China, i.e., the Eastern Central and Southeastern areas.

Development of hydraulic power unit and accumulator charging circuit for electricity generation,storage and distribution

It is the purpose of the present paper to convert hydraulic energy to electric energy and saves both the pressure and electrical energy for re - use during the next system upstroke using two secondary units coupled to induction motor to drive cylinder loads. During upstroke operation, the variable pump/motor （P/M） driven by both electric motor and the second （P/M） works as hydraulic pump and output flow to the cylinders which drive the load. During load deceleration, the cylinders work as pump while the operation of the two secondary units are reversed, the variable （P/M） works as a motor generating a torque with the electric motor to drive the other （P/M） which transforms mechanical energy to hydraulic energy that is saved in the accumulator. When the energy storage capacity of the accumulator is attained as the operation continues, energy storage to the accumulator is thermostatically stopped while the induction motor begins to work as a generator and generates electricity that is stored in the power distribution unit. Simulations were performed using a limited PT2 Block, i.e. 2nd-order transfer function with limitation of slope and signal output to determine suitable velocity of the cylinder which will match high performance and system stability. A mathematical model suited to the simulation of the hydraulic accumulator both in an open-or close-loop system is presented. The quest for improvement of lower energy capacity storage, saving and re-utilization of the conventional accumulator resulting in the short cycle time usage of hydraulic accumulators both in domestic and industrial purposes necessitates this research. The outcome of the research appears to be very efficient for generating fluctuation free electricity, power quality and reliability, energy saving/reutilization and system noise reduction.

Feasible design for electricity generation from Chlorella vulgaris using convenient photosynthetic conditions

Many recent studies are concerned with low cost,easy to handle and alternative renewable energy as a feasible solution for the upcoming crisis of energy shortage.Microalgae are unicellular entities the can only depend on CO_(2),water and solar power to cover their nutritional needs.The current study is concerned with using algal cells in a polymeric hydrogel,as a cheap source of energy for electricity generation.Chlorella vulgaris has been proved to be a promising algal species for electricity generation,as compared with Micractinium reisseri.PVA hydrogel has been used for the immobilization of both algal species in order to protect them from the adverse surrounding conditions in addition to its ability to slowly release the required water molecules according to needs.Under these conditions,C.vulgaris showed the ability to generate 60 mV compared with 15 mV generated by M.reisseri.Scanning electron micrographs showed nano-threads that bind the C.vulgaris cells to each other,indicating the ability of algae to create nanowires that facilitate the electron transfer among algal cells and from cells to the nearest electrode.However,we would expect an increase in the produced potential with simultaneous amendment of environmentally polluted water,such as sewage or waste water.Both of FTIR and raman spectroscopy proved the presence of the characteristic groups of PVA hydrogel and proved the proper integration of the algal cells inside the hydrogel cavities.

Towards an Ethical and Ecological Approach to Electricity Generation: A Comparative Analysis of Coal and Nuclear Power in the USA

According to the US Energy Information Administration, about 4118 billion kilowatt-hours (kWh) electricity was generated at large-scale generation facilities in 2019. About 63% of this was from fossil fuels, e.g., coal, natural gas, petroleum, and other gases. Environmental exposure to particulates, sulfur dioxide, nitrogen oxides, mercury, arsenic, radioactive fly ash, and other pollutants are extremely detrimental to the human cardiovascular, respiratory, and nervous systems. Such exposure increases the risk of lung cancer, stroke, heart disease, chronic respiratory diseases, respiratory infections, and other illnesses. In light of the challenges associated with renewables providing large quantities of base load power, as well as other factors, the benefits offered by nuclear power should be reexamined by policy makers to move the country towards a more ecological and ethical method of electric power production. This paper offers a concise analysis of many of the salient issues, comparing electricity generation from coal plants and light water nuclear reactors.

Technical Analysis: Generation of Electricity by Pyrolysis of Plastics in a Canadian Environment

The study takes motivation from provincial and national issues regarding waste management and electricity production in Canada.Most sources include previous research relating pyrolysis’applications in different parts of the world.The research included 2-3 weeks of extensive reading of previous research and understanding the theory relating polymers.Research has been conducted to understand why polymers have the properties that they do.Thorough analysis about the chemical reactions relating polymers on a small and large scale is conducted.More research was conducted relating to socio-economic conditions of Canada and Singapore for application purposes.Findings of the research point to an addition the Canadian government can uphold i.e.,build more plastic pyrolysis plants in different regions for waste management.Our findings also suggest that the short term spending on such projects can yield long term benefits.This research is important because it will solve Canada’s non-recyclable waste problems,it will help bring in a new source of electricity and it will help increase the budget of municipalities in the long run.This paper is not just informative on polymers,but also will help readers understand issues regarding Canadian waste management and propose possible solutions.

National Electricity Generation,Electricity Consumption and Peak Load by Grid (April 2006)

Statistics on electricity generation and time of frequency over-limit;Statistics on electricity consumption and peak load.

National Electricity Generation,Electricity Consumption and Peak Load by Grid (March 2006)

Statistics on electricity generation and time of frequency over-limit;Statistics on electricity consumption and peak load.

Electricity generation grew steadily

In the first half of 1996, electricity generation in China had steadily, grown with a total electricity generation accumulated to 508.3 TWh, it was 47.5% of the planned figure in the year, and 8.3% higher than the same period of previous year. Among the generation, hydro-electricity amounted to 78.2 TWh, 5.39% lower than previous year, thermal electricity amounted to 424.55 TWh, 10.87% higher than previous year, nuclear electricity amounted to 5.52 TWh, 47.15% higher than previous year. The steady growth of thermal electricity might attribute to newly installed generating capacity in one hand, and the

Promoting and controlling electron transfer of furfural oxidation efficiently harvest electricity,furoic acid,hydrogen gas and hydrogen peroxide

Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidation needs input of external electric energy.Herein,we developed a liquid flow fuel cell(LFFC)system to achieve oxidation of furfural in anode for furoic acid production with co-production of hydrogen gas.By controlling the electron transfer in cathode for reduction of oxygen,efficient generation of electricity or production of H_(2)O_(2)were achieved.Metal oxides especially Ag_(2)O have been screened as the efficient catalyst to promote the oxidation of aldehydes,while liquid redox couples were used for promoting the kinetics of oxygen reduction.A novel alkaline-acidic asymmetric design was also used for anolyte and catholyte,respectively,to promote the efficiency of electron transfer.Such an LFFC system achieves efficient conversion of chemical energy of aldehyde oxidation to electric energy and makes full use the transferred electrons for high-value added products without input of external energy.With(VO_(2))_(2)SO_(4)as the electron carrier in catholyte for four-electron reduction of oxygen,the peak output power density(Pmax)at room temperature reached 261 mW/cm^(2)with furoic acid and H_(2)yields of 90%and 0.10 mol/mol furfural,respectively.With anthraquinone-2-sulfonate(AQS)as the cathodic electron carrier,Pmaxof 60 mW/cm^(2)and furoic acid,H_(2)and H_(2)O_(2)yields of 0.88,0.15 and 0.41 mol/mol furfural were achieved,respectively.A new reaction mechanism on furfural oxidation on Ag_(2)O anode was proposed,referring to one-electron and two-electron reaction pathways depending on the fate of adsorbed hydrogen atom transferred from furfural aldehyde group.

Electricity Generation and the Present Challenges in the Nigerian Power Sector

National development requires adequate electricity supply of which all activities--generation, transmission and distribution leading to it are capital-intensive in terms of funds, natural and human resources. The dwindling power sector government funding coupled with low private sector participation and weak level political will require creative and innovative solutions in addressing the power supply problem in Nigeria. Hence, this paper seeks to examine power sector privatization as a viable option.

Electricity Generation by Solar Energy in Turkey： Current State and Outlook

Turkey is in good condition in terms of solar energy because of the fact that, Turkey falls in between 40 degree North and 40 degree South latitude which is called as ＂sunbelt＂. The potential of producing electric from solar energy is very high in terms of potential of Turkey. According to a report by the Turkish Energy Ministry, Turkey＇s average rate of electrical energy consumption increased to levels 5.59 in the last 11 years. Moreover, solar energy may be primary energy source on account of the fact that, Turkey is in the position of a country importing energy and has signed Kyoto Protocol of carbon emission to atmosphere. The aim of the article is to give information about acts need to be done and present policies of Turkey on producing electric from solar energy. Beyond question, the policies of the government will determine the direction of developmental momentum of energy industry in Turkey as whole world will. The present support to production of electric from solar energy is not enough, so it is needed to give much higher level of support to this sector. In this context, it is essential to enhance guarantied tariff cost and the power of unlicensed electric production.

CO2 Emission from Electricity Generation in Malaysia： A Decomposition Analysis

In tenth Malaysian Plan, Malaysian government had voluntarily targeted to reduce its emission intensity to 40% compared to the 2005 level by the year 2020 and recently re-pledge to reduce more and declared for 45% emission reduction by 2030. Looking at the country＇s high dependency to the fossil fuel generation it is a high concern on the increasing CO2 emission in Malaysia. This paper intends to analyze the current status of CO2 emissions from electricity generation in Malaysia during the period 1992-2014 by applying the LMDI （logarithmic mean Divisia index） technique to find the nature of the factors influencing the changes in CO2 emissions. The decomposition analysis observed three biggest factors contributed to the reduction of CO2 emission throughout the period which is thermal generation effect, electricity generation efficiency effect and electricity structure effect.

Electricity Storage With High Roundtrip Efficiency in a Reversible Solid Oxide Cell Stack

We theoretically investigate the electricity storage/generation in a reversible solid oxide cell stack. The system heat is for the first time tentatively stored in a phase-change metal when the stack is operated to generate electricity in a fuel cell mode and then reused to store electricity in an electrolysis mode. The state of charge （H2 frication in cathode） effectively enhances the open circuit voltages （OCVs） while the system gas pressure in electrodes also increases the OCVs. On the other hand, a higher system pressure facilitates the species diffusion in electrodes that therefore accordingly improve electrode polarizations. With the aid of recycled system heat, the roundtrip efficiency reaches as high as 92% for the repeated electricity storage and generation.

Insights into the role of oxygen-containing functional groups on carbon surface in water–electricity generation

A deep understanding of the electricity generation mechanism from the interaction between water molecules and carbon material surfaces is attractive for next-generation water-based energy conversion and storage systems.Herein,an asymmetric generator was assembled based on functionalized carbon nanotubes films to investigate the relative contribution from various oxygen functional groups on carbon surface to the water-electrical performance.Experiments and calculations demonstrate that the electricity mainly originates from the water molecule adsorption by carboxyl groups and dissociation of functional groups on carbon surface,which leads to the formation of electrical double layers at interfaces.This device allows the electricity generation with a variety of water sources,such as deionized water,tap water,as well as seawater.In particular,the generator based on carboxyl carbon nanotubes can induce a voltage of over 200 mV spontaneously in natural seawater with the power density of about 0.11 mW·g^(−1).High voltages can be achieved easily through the series-connection strategy to power electronic products such as a liquid crystal display.This work reveals the dominant role of carboxyl groups in carbon-based water–electricity conversion and is expected to offer inspiration for the preparation of carbon materials with high electrical performance.

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

Oily wastewater from ocean oil spills endangers marine ecosystems and human health. Therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bottom-layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bottom “bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. Therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 W/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. This work provides a green and cost-effective path for the separation of oil-water mixtures.