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The article focuses on the renewable technologies, which were discussed in the three papers presented during the 10th International Congress of the Mexican Society of Hydrogen "Renewable Energies," held from September 27 to October 1, 2010 in Toluca, Mexico. It says that a large solar-derived energy source is represented by biomass. It adds that large amounts of carbon dioxide is produced by the industrial conversion of methane into hydrogen.

Due to the depletion of fossil resources and the increase in carbon dioxide emissions, renewable energy systems (RESs) such as photovoltaic (PV) and wind generator (WG) have become an active player in power systems (PSs). In Japan, diesel generators (DGs) are the means of power generation in most isolated islands. Therefore, the introduction of RESs into these islands is of great importance. However, due to the uncertainty of RESs, battery energy storage systems (BESSs), fuel cells (FCs) and exploiting the electric vehicles (EVs) owned by customers are expected as vital power sources for the next generation. Moreover, demand response programs are utilized in this paper. As a result of reforming PSs in recent years, transactions on power markets have also been increasing in Japan. The Japan electric power exchange provides day-ahead market, intraday hour-ahead market, and forward market. It is expected that these markets make it possible to deal with uncertainties related to the generated power fluctuation. This paper presents the optimal operation method for multi-area PSs consisting of DG, PV, WG, BESS and FC by using chance-constrained programming. The proposed method has achieved reduction of the total operational cost of the multi-area small power systems by using FC, household EVs and two power markets. [ABSTRACT FROM AUTHOR]

Geothermal heat pumps have several advantages over conventional heating and cooling systems. They can operate in both winter and summer, have high efficiencies, and do not directly emit any greenhouse gases during operation. Investors (in developing countries) can use Clean Development Mechanism as a source of financing for new or existing renewable energy facilities by selling Certified Emission Reductions credits (CERs), which represent the amount of CO2 emission (1 CER¼1 tCO2eq) that is avoided using renewable energy. The aim of this paper is to analyze the possibility of CO2 reduction by using geothermal heat pumps for fossil fuel displacement with applying Clean Development Mechanism. Results have shown that by using geothermal heat pumps during a 7-year crediting period, the estimated emission reduction would be 79.45 tCO2 (equal to 80 CERs), enabling the investor to achieve profit from selling 80 CERs and thus helping to fund the proposed project activity. Three main factors which influence the amount of CO2 reduction have been identified: carbon-dioxide emission factor for electricity source, efficiency of technology used for baseline scenario, and coefficient of performance (COP) of heat pumps. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present new evidence of relationship between economic activities and environmental conditions, and accordingly to obtain emission-cutting focus in China. This study decomposes total CO2 emissions into six determinants derived from three net effects of Environmental Kuznets Curve (EKC): scale, technique, and composition. Meanwhile, in views of huge provincial-disparity in economic situation and environmental conditions, we investigate impact factors of CO2 emissions at sub-national level via generalized method of moment estimation. Test including panel unit root, panel cointegration, Sargan and residual auto-correlation is also performed to maintain strict structure and scientific estimation. Results show that CO2 emissions substantially increase over a decade with an upward annual growth rate and a high provincial disparity; sorted in descending order, previous CO2 emissions, coal share, economic growth, and industrial energy consumption are main determinants for accelerated CO2 emissions; EKC with an inverted-U shape relationship between environment quality and income is not verified. Accordingly, emission-reducing policies at sub-national level are concluded. [ABSTRACT FROM AUTHOR]

Integrated energy systems (IESs) have attracted increasing attention in recent years due to the high energy efficiency and low emission of carbon dioxide. To deal with the limitation of single IES, distributed energy networks consisting of multi-IESs are proposed to improve the complementarity of both the energy supply and the demand. This paper mainly focuses on the day-ahead energy management of the whole energy network for the economic operation of the system, following which, a cooperative game is formulated to determine the optimal strategy of each IES to minimize the coalition daily cost. Meanwhile, an allocation mechanism is designed from the perspective of probability to allocate coalition cost to each IES. According to the results of the numerical study, the proposed approach can improve the economic performance of both the energy network and the individual IES by interchanging electrical and thermal energies in the network. [ABSTRACT FROM AUTHOR]

After the disaster in the Tohoku region of Japan, as a part of recovery projects, wave energy has been drawing attention. To promote wave energy technologies, including wave energy converters (WECs), this study aims to present comprehensive analyses of wave climates around Kyushu, which is the southernmost and third largest of Japan's four main islands. This paper calculates wave climate around Kyushu for ten years (2007–2016) using the Simulating WAves Nearshore model with an approximately 800 m high spatial and 1-h temporal resolution. The results reveal that the south side of Kyushu has more energetic waves than the north and the southeast has the strongest energy among neighboring seas of Kyushu. In the southeast, the major portion of the wave energy transport is generated by extreme weather events. Wave climates in the southwest are less affected by extreme weather events, and the wave energy transport shows the opposite tendency to that of the southeast, suggesting that wave energy production in the southeast and southwest can supply high stable energy. Statistical wave characteristics in the southeast and southwest also show markedly different tendencies to each other, which provides vital information for future designing, deploying, and tuning of WECs on the south side of Kyushu. [ABSTRACT FROM AUTHOR]

Microalgae are considered a promising biofuel resource to fix carbon dioxide (CO2), which can support social development and environmental improvement in the future. In this paper, characteristics of microalgae growth with two parameters of solar radiation and ambient temperature are investigated based on industrial-scale microalgae bulk growth model of Quinn et al. By using this model, the potential biomass production of microalgae in China is estimated based on data of the available untilled lands and the weather to be 7.38 × 109 tonnes. This is 2.4 times larger than China's energy consumption of 3.08 × 109 tonnes standard coal equivalent in 2010, and satisfies that predicted with an exponentially increasing trend for 2020, and 89% of the amount predicted for 2030. The annual total CO2 emissions reduced is estimated to be 13.5 × 109 tonnes, which can improve the natural environment besides supplying sustainable production in China. [ABSTRACT FROM AUTHOR]

In 2009, the National Research Council issued Electricity from Renewables: Status, Prospects, and Impediments the study report of the Panel on Electricity from Renewable Sources. As part of the larger America's Energy Future study undertaken by the National Academies, the panel was asked to examine the technical potential for development and deployment of renewable electricity technologies. This paper summarizes the report by this panel. The panel noted that renewable electricity generation technologies represent a tremendous opportunity to provide low net carbon dioxide (CO2)-emitting electricity generation from domestic resources and to generate new economic opportunities for the United States. The panel found that there are sufficient domestic renewable resources and technologies to allow renewable electricity to play a significant role in future electricity generation. However, although wind and solar electricity in particular have exhibited very large growth rates, non-hydropower renewables still provide a small percentage of total US electricity generation. The study considered the size and distribution of the resource base; the status of renewable electricity technologies; the economics of renewable electricity in light of various policy options; the environmental impacts of electricity from renewable resources; and the issues related to scaling up deployment. The panel concluded that an aggressive but achievable future for renewables could have non-hydroelectric renewables contributing 10% of the nation's electricity generation by 2020 and 20% or more by 2035. To reach these levels, significant and sustained actions, involving a combination and coordination of policy, technology, and capital, will be essential. The panel emphasizes policy, technology, and capital equally because the scale of the effort required to reach such levels brings significant challenges beyond simple resource availability or technical capabilities. [ABSTRACT FROM AUTHOR]

N-ethylmonoethanolamine (EMEA) and N-N-diethylmonoethanolamine (DEMEA) can be prepared from renewable resources and appear to be commercially attractive solvents for post-combustion CO2 capture by absorption/stripping process. In this paper, the thermal degradation of these renewably prepared amines was studied at 423 K and compared with other amines such as monoethanolamine, diethanolamine, triethanolamine, and N-methyl diethanolamine. Furthermore, an investigation of the kinetics of thermal degradation of aqueous EMEA and DEMEA was conducted by using a 600 ml high-temperature high-pressure reactor in the temperature range of 393 to 423 K and amine concentration range of 1 to 3 kmol m-3, respectively. Estimation of the active solvent content of the reaction mixture samples obtained during the degradation experiments was performed using a gas chromatograph (GC) equipped with a Flame Ionization Detector (FID) and a Tenax GC column. The obtained results indicate that the rate of thermal degradation of both aqueous EMEA and DEMEA increases with the increase in the initial amine concentration and temperature. Additionally, the degradation reaction was observed to be first order with respect to the initial amine concentration. Two intrinsic kinetic power law models were formulated to describe the kinetics of the thermal degradation of aqueous EMEA and DEMEA and the kinetic parameters were predicted by using the linear least-squares regression analysis. The kinetic rate constants for the thermal degradation of these renewably prepared amines were determined (both experimentally and by the models) and on the basis of their temperature dependency, the activation energy for the degradation reaction was estimated. This work represents the first attempt towards obtaining the intrinsic kinetic data for thermal degradation of aqueous EMEA and DEMEA and formulating a kinetic model that fits the data based on the initial rate of degradation. [ABSTRACT FROM AUTHOR]

Several models, about the power performance prediction for the Darrieus wind turbines, have been developed during the last decades. Among these models, an enhanced multiple stream tubes model, LDWT (Lee-Darrieus Wind Turbine model) for Darrieus wind turbine blade with experimental aerofoil characteristics showed simple, fast, and precise results, without time consuming, of solving Reynolds Averaged Navier-Stokes equation for the complex air flow passing through rotational blade. Recent interest has been paid on the straight Darrieus rotor blade (H-Darrieus rotor) because of its several advantages over the curved blades. However, few reports cover its power performance prediction model. In this paper, the LDWT was extended into the H-Darrieus rotor with 2-dimensional experimental data and stall delay model. From results for the high solidity H-Darrieus rotor, LDWT underestimate the test data without stall delay model, but it shows dramatically well matching with test data when stall delaying is calculated additionally in the model. Therefore, it is shown that the model with stall delaying can be used for the design and analysis of H-type vertical wind turbine blade without solving of Navier-Stokes equation. [ABSTRACT FROM AUTHOR]

In this paper, three typical agriculture residues (corn cob (CC), peanut shell (PS), and pine cone (PC)) from northeastern China were investigated for fast pyrolysis to produce bio-oil. The influences of carrier gas velocity, temperature, and particle size of biomass on bio-oil yield were studied. With the increase of carrier gas velocity, the bio-oil yield increased, but the increase rate of bio-oil yield first increased and then decreased. As temperature increased, the bio-oil yield first increased and then decreased. The variation trends of bio-oil yield with particle size for the three biomasses were different. For CC, the bio-oil yield increased with the reduction of the granularity; but it was completely opposite for PS and PC. The main components of the exhaust gas were CO2, CO, H2, and small quantities of CHx. The compounds of bio-oil were mostly with oxygen functional groups, resulting in the higher content of oxygen element, then leading to low calorific value. [ABSTRACT FROM AUTHOR]

The emerging technology of biomass/CO2 gasification to recover waste heat from granulated blast furnace (BF) slag for solving the energy crisis and relieving the greenhouse effect was proposed. The gasification performances of biomass/CO2 in granulated BF slag under different reaction temperatures and mole ratios of CO2 to fixed carbon in the biomass (CO2/C) were investigated and the effects of granulated BF slag on the biomass/CO2 gasification reaction were illuminated. The results showed that with higher gas content, gas yield, and lower heating value (LHV) were obtained with higher reaction temperature. When CO2/C was up to 1, the maximum concentrations of CO and H2 were obtained and the LHV was near maximum value. Granulated BF slag could promote biomass/CO2 gasification reactions to some degree and also could act as a catalyst in the reaction. Under the optimum conditions, a reaction temperature reaching 1000°C, CO2/C of 1 and using granulated BF slag as a heat carrier, the maximum syngas concentrations of CO and H2 were 43.1% and 33.7%, and the gas yield and LHV were 1.453 m3/kg and 16.089MJ/kg, respectively. [ABSTRACT FROM AUTHOR]

Wind power reduces our exposure to fuel price volatility and abrupt supply disruptions; it has no CO2 emissions and increases energy security through the diversification of the energy portfolio. If well sited and dimensioned, wind farms may contribute to decreased electricity generation costs. This article presents a combined GISs (Geographical Information Systems) and CBA (Cost Benefit Analysis) approach, in determining the most feasible sites that would be suitable for the generation of wind energy in Terceira Island, which is aimed towards efficient policy designs. Data corrected with Wind Atlas Analysis and Application Program, from local effects of the territory, are used to determine potential energy. Furthermore, a CBA is performed, without taking into consideration subsidies and economic indicators are displayed in maps using GIS. Results indicated that Terceira Island has large available areas capable of generating wind energy at low prices. On Terceira Island, while considering a 1500kW wind farm under the best siting conditions, it is estimated to achieve a Net Present Value of nearly 3 330 000.00 e, an Internal Rate of Return of nearly 26%, and a Levelized Cost of Energy of nearly 0.04 €/KW h, without incentives. The sensitivity analysis results indicated that reductions in the energy sold may drastically impair the feasibility of a wind energy generation project, and that increases in the lifetime of a project from 15 to 25 years may improve its feasibility. The minimum wind speed required to grant feasibility of investments on Terceira Island, for 1500kW installed power, is 6m/s, ceteris paribus. This analysis pointed out that Serra do Cume and Serra da Ribeirinha are the most suited for wind energy projects on Terceira Island. [ABSTRACT FROM AUTHOR]

A comparative cost/benefit and energy balance analysis addresses the critical scientific and technical challenges that impact the economic feasibility of synthesizing up to 100 000 gal per day of jet fuel at sea using carbon dioxide (CO2) and hydrogen (H2) from the sea. Included in this analysis are the capital cost, operation and maintenance, and electrical generation cost for synthesizing jet fuel at sea using either ocean thermal energy conversion or nuclear power processes as the energy source. The results suggest that jet fuel could be produced at sea for $3 to $6/gal. Comparing these costs with current and historical prices of fuel purchased by the Department of Defense provides insight into the economic and operational benefits of a sea-based fuel synthesis process for the Navy. [ABSTRACT FROM AUTHOR]