Effects of climate change on wind energy production in Iran

Arabian Journal of Geosciences - This study explores the effect of future climate change on wind energy conversion in Iran, based on data from existing wind farms. In an effort to estimate and...     

Renewable energy in Iran: Challenges and opportunities for sustainable development

Around the globe, developing countries have reported different cases of successfully implemented Renewable Energy (RE) program supported by bilateral or multilateral funding. In developing countries subsidy has played a big role in RE program marketing and whether this will lead to sustainable development is yet to be determined. The adoption of implementation strategies that will support sustainable development and overcoming barriers that hinder expansion of Renewable Energy Technologies (RETs) still remains as a big challenge to stakeholders involved in promotion of RE resources in developing countries. In this respect, developing countries need to re-examine their environmental policy for promotion of RETs in order to define its role in revitalization of their economies. This paper reviews the policy incentives for promotion of RETs in the Islamic Republic of Iran. Setting-up international collaborative business ventures between local industry in Iran and RE companies in developed countries is proposed as an implementation strategy that will appropriate diffusion of RETs in the country. An organizational framework that may help to attain this objective is discussed and a structural model for RE business partnership is presented. It is concluded that with appropriate policy formulations and strategies, RETs can bring about the required socio-economic development in Iran.     

Iran’s energy policy: Current dilemmas and perspective for a sustainable energy policy

Iran is facing large challenges in the area of energy policy. In order to illuminate these challenges and the problems and possibilities, which are present, firstly, the current energy consumption patterns have been analyzed in Iran as well as the energy policy of the Iranian government. Based on this analysis, the alternative concepts have been then formulated for Iran’s future energy. The increase in energy usage in Iran is distinctly out of proportion with the development of economic productivity. Negative structural characteristics of this system are: first, an above average energy intensity; second, an increase in energy consumption in the traffic sector; third, a high growth rate in usage of electric energy; and lastly, an above-average amount of stress to the environment. Traditionally, Iran’s energy policy has focused on satisfying the growing demand for energy by oil and, in the last fifteen years, by successively expanding natural gas. However, the further development of the natural gas supply only makes sense within the context of a holistic energy policy, which takes into account the principles of sustainable development. In the short term, such a policy would take advantage of both considerable energy saving techniques, as well as potential renewable energy sources. In the long term, such a policy would strive for the complete transfer to renewable energy sources and technology.     

Coalbed methane in the Ruhr Basin, Germany: a renewable energy resource?

Around the globe underground hard coal mining leads to a release of methane into the atmosphere. About 7% of the global annual methane emissions originate from coal mining. In the year 2002, 16 countries used coal gas to generate heat and electricity. In many cases, the exact size of coalbed methane reservoirs is not identified. The possibility of a long-term gas production and its profitability at single sites are unknown. To clarify these points, the processes of gas generation as well as the gas-in-place volume have to be determined. Both issues are tackled here for the Ruhr basin. Within this basin, coal gas samples were taken at 13 gas production sites, spread over three samplings within 14 months. There were virtually no changes in the concentrations of gas components at single sites within this period. The isotope composition of methane (δ¹³C-methane: −40.0 to −57.3‰ vs. PDB) revealed that the produced methane is a mixture of gases of thermogenic and microbial origin. The microbial contribution of methane seems to be more pronounced at sites of active and especially abandoned coal mining than at unmined places. Ethane and propane are of thermogenic origin, with ethane's isotopic composition tending to heavier values (richer in ¹³C) with time. This time-dependent phenomenon is interpreted as being caused by desorption. In addition, living methanogenic archaea were detected in mine water samples from depths down to 1200 m.     

Hot dry rocks: An inexhaustible and renewable source of energy

Geological, methodological, and economic aspects of the production and utilization of petrother mal resources (heat of “dry” rocks) for electric energy production and heat supply are considered. Possibility of the utilization of natural fracture zones or artificial fissure zones, which are created by hydraulic fracturing of underground rock massifs, is noted. Application of new tools for drilling deep wells makes the petrochemical energy competitive relative to both other types of renewable resources and traditional organic fuel.     

Challenges of renewable energy development and deployment in Ghana: perspectives from developers

GeoJournal - Renewable energy is key to the development of Ghana’s power sector especially for the replacement of fossil fuels, which have become much a talk globally for contributing to...     

Analysis of recovery efficiency in high-temperature aquifer thermal energy storage: a Rayleigh-based method

High-temperature aquifer thermal energy storage (HT-ATES) is an important technique for energy conservation. A controlling factor for the economic feasibility of HT-ATES is the recovery efficiency. Due to the effects of density-driven flow (free convection), HT-ATES systems applied in permeable aquifers typically have lower recovery efficiencies than conventional (low-temperature) ATES systems. For a reliable estimation of the recovery efficiency it is, therefore, important to take the effect of density-driven flow into account. A numerical evaluation of the prime factors influencing the recovery efficiency of HT-ATES systems is presented. Sensitivity runs evaluating the effects of aquifer properties, as well as operational variables, were performed to deduce the most important factors that control the recovery efficiency. A correlation was found between the dimensionless Rayleigh number (a measure of the relative strength of free convection) and the calculated recovery efficiencies. Based on a modified Rayleigh number, two simple analytical solutions are proposed to calculate the recovery efficiency, each one covering a different range of aquifer thicknesses. The analytical solutions accurately reproduce all numerically modeled scenarios with an average error of less than 3 %. The proposed method can be of practical use when considering or designing an HT-ATES system.     

Thermal comfort and forecast of energy consumption in Northwest Iran

Assessing the climatic characteristics and identifying the climatic parameters of a specific region can play a major role in human welfare. Thermal comfort conditions are among the most significant factors of climatic variables in the northwestern regions of Iran due to the considerable spatial and temporal variations and are vital for environmental, energy and economic management. It is therefore necessary to advance our knowledge of the climatic conditions in order to provide an appropriate tool for managing climatic extremes. This requires charting of the range of clusters of the thermal comfort conditions in this region. In this study, the general atmosphere circulation model HADCM3 and the A1 scenario, downscaled by the LARS-WG model, were employed to simulate the climatic conditions in Iran during the period 2011–2040. The data obtained were compared with sampled data from six Iranian climatic stations for the 30-year period (1961–1990). In order to tabulate this comparison, six clusters per climatic station were defined based on intrinsic similarity of data. Results show an increase in the annual average temperature of these six stations by 1.69 °C for the predicted years, projected from the base years 1961–1990. This factor has resulted in an increment of the annual average thermal comfort temperature inside buildings by a magnitude of 0.52 °C in future decades. When the thermal requirements of the studied region were evaluated based on the real temperature difference and the degree of thermal comfort, it becomes clear that apart from cluster 1, the energy required to reach thermal comfort inside buildings will increase in the future. As a result of this temperature increase, an increase of the energy required to reach the thermal comfort is expected. This new methodology is an interesting tool and needs to be seriously considered by engineers and architects in designing buildings of the future.     

Modeling and mapping of solar radiation using geostatistical analysis methods in Iran

Because of economic and technical limitations, measuring solar energy received at ground level (R _s ) isn’t possible in all parts of the country, and in only 12% of synoptic stations is this parameter measured and recorded. Thus, it should be estimated and modeled spatially based on other climatic variables using mathematical methods. In this research, many attempts have been made to introduce an air temperature-based model for Rs estimation, and then, based on the output of the mentioned models, several geostatistical methods have been tested, and finally an elegant spatial model is proposed for (Rs) zoning in Iran. In this regard, the relationships between the measured amounts of monthly solar radiation and other climatic parameters, such as a monthly average, maximum and minimum temperature, precipitation, relative humidity, and the number of sunny hours during the period 1970–2010, are examined and modeled. It was revealed that based on the linear relationship between the monthly average air temperatures and solar radiation values recorded in each of the stations, that the best-fit linear model, with R ²  = 0.822, MAE = 1.81, RMSE = 2.51%, and MAPE = 10.08, can be introduced for Rs estimation. Then, using the outputs of the proposed model, the amounts of (R _s ) are estimated in another 171 meteorological stations (a total of 192 stations), and eight geostatistical methods (IDW, GPI, RBF, LPI, OK, SK, UK, and EBK) were investigated for zoning. Comparing the resulting variograms showed that in addition to proof of spatial correlation between solar radiation data, they can be applied for modeling changes in various directions. Analyzing the ratio of the nugget effect on the roof of the variograms showed that the Gaussian model with the lowest ratio (Co/Co + C = 0.883) and (R ²  = 0.972), could model the highest correlation between the data and, therefore, it was used for data interpolation. To select the best geostatistical model, R2, MAE, and RMSE were used. On this basis, it was found that the RBF method with R ²  = 0.904, MAE = 3.02, RMSE = 0.39% is the most effective. Also, the IDW method with R ²  = 0.90, MAE = 3.08, RMSE = 0.391%, compared to other methods is the most effective. In addition, for data validation, correlations between observed and estimated values of solar radiation were studied and found R ²  = 0.86.     

Implementing energy efficiency for target setting in the sugar industry of Iran

Sugar plants are one of the most energy-consuming industries in Iran; thus, the implementation of measures to improve energy efficiency seems necessary for such industries. This paper investigated sugar plants’ efficiency in different stages for implementation process of energy efficiency measures focusing on determining some relations for benchmarking and reaching efficient status. In doing so, the process of implementation of energy efficiency improvement measures is planned on the basis of experts’ opinions. Also, for deriving the efficiency of each plant in each of the stages of implementation of measures and the aggregate efficiency of them a multi-stage data envelopment analysis model is formulated. The obtained results from average efficiency indicated that the under evaluation population in the first, second, third, and fifth stages have a good performance and in the fourth-stage managers could not perform successfully. Also, the results of determining some relations for benchmarking showed that to what extent each of the outputs of each stage of the implementation process of energy efficiency measures in the sugar plants should be changed in order to achieve efficient conditions. The distance between the current output and the desirable output indicates to what extent manager has been successful in operation, studies of the rate of change of each of the outputs to achieve the efficient conditions are of the utmost importance in developing suitable strategies.     

Electrokinetic Biofence, remediation of VOCs with solar energy and bacteria

Since April 2001, an Electrokinetic Biofence (EBF) is in operation at the site of a chemical laundry at Wildervank in the Province of Groningen in the Netherlands. The EBF is located at the western part of the building and covers an area of 10×2 m=20 m². Prior to the installation of the fence, the top soil, heavily polluted with volatile chlorinated hydrocarbons (VOCs), has been removed. The fence consists of a row of alternating cathodes and anodes with a mutual distance of 5 m. Upstream of the line of electrodes, a series of infiltration wells were installed, which have been periodically filled with nutrients. The aim of the EBF is to enhance biodegradation of the VOCs in the groundwater at the zone of the fence by electrokinetic dispersion of the dissolved nutrients in the groundwater. After running the EBF for nearly 2 years, clear results have been observed. The concentration of nutrients in the zone has increased, the chloride index is decreasing, and VOCs are being dechlorinated by bio-activity. The electrical energy for the EBF is being supplied by solar panels.     

Argon, krypton, and xenon in the bulk solar wind as collected by the Genesis mission

We present bulk solar wind isotopic and elemental ratios for Ar, Kr, and Xe averaged from up to 14 individual analyses on silicon targets exposed to the solar wind for ∼2.3 years during NASA’s Genesis mission. All averages are given with 1σ standard errors of the means and include the uncertainties of our absolute calibrations. The isotopic ratios ⁸⁶Kr/⁸⁴Kr and ¹²⁹Xe/¹³²Xe are 0.303 ± 0.001 and 1.06 ± 0.01, respectively. The elemental ratios ³⁶Ar/⁸⁴Kr and ⁸⁴Kr/¹³²Xe are 2390 ± 120 and 9.9 ± 0.3, respectively. Average fluxes of ⁸⁴Kr and ¹³²Xe in the bulk solar wind in atoms/(cm² s) are 0.166 ± 0.009 and 0.017 ± 0.001, respectively. The flux uncertainties also include a 2% uncertainty for the determination of the extracted areas. The bulk solar wind ³⁶Ar/³⁸Ar ratio of 5.50 ± 0.01 and the ³⁶Ar flux of 397 ± 11 atoms/(cm² s) determined from silicon targets agree well with the ³⁶Ar/³⁸Ar ratio and the ³⁶Ar flux determined earlier on a different type of target by Heber et al. (2009). A comparison of the solar wind noble gas/oxygen abundance ratios with those in the solar photosphere revealed a slight enrichment of Xe and, within uncertainties a roughly uniform depletion of Kr-He in the solar wind, possibly related to the first ionization potentials of the studied elements. Thus, the solar wind elemental abundances He-Kr display within uncertainties roughly photospheric compositions relative to each other. A comparison of the Genesis data with solar wind heavy noble gas data deduced from lunar regolith samples irradiated with solar wind at different times in the past reveals uniform ³⁶Ar/⁸⁴Kr ratios over the last 1-2 Ga but an increase of the ⁸⁴Kr/¹³²Xe ratio of about a factor of 2 during the same time span. The reason for this change in the solar wind composition remains unknown.     

Evaluating the impacts of watershed management on runoff storage and peak flow in Gav-Darreh watershed,Kurdistan, Iran

Recently, water and soil resource competition and environmental degradation due to inadequate management practices have been increased and pose difficult problems for resource managers. Numerous watershed practices currently being implemented for runoff storage and flood control purposes have improved hydrologic conditions in watersheds and enhanced the establishment of riparian vegetation. The assessment of proposed management options increases management efficiency. The purpose of this study is to assess the impact of watershed managements on runoff storage and peak flow, and determine the land use and cover dynamics that it has induced in Gav-Darreh watershed, Kurdistan, Iran. The watershed area is 6.27 km² which has been subjected to non-structural and structural measures. The implemented management practices and its impact on land use and cover were assessed by integrating field observation and geographic information systems (GIS). The data were used to derive the volume of retained water and determine reduction in peak flow. The hydrology of the watershed was modeled using the Hydrologic Engineering Center–Hydrologic Modeling System (HEC–HMS) model, and watershed changes were quantified through field work. Actual storms were used to calibrate and validate HEC–HMS rainfall–runoff model. The calibrated HEC–HMS model was used to simulate pre- and post-management conditions in the watershed. The results derived from field observation and HEC–HMS model showed that the practices had significant impacts on the runoff storage and peak flow reduction.     

Anglo-Saxon and German approaches to neoliberalism and environmental policy: The case of financing renewable energy

‘Renewable electricity certificate’ trading systems that have been established to promote renewable energy in the UK are a form of neoliberal environmental governance introduced to assimilate environmental objectives with neoliberal hegemony. However, in this case, neoliberal ideological objectives have not been translated into practice since the British Renewable Obligation is not performing as efficiently as its proponents hoped. By contrast, so-called ‘Renewable Energy Feed-in Tariff’ (REFIT) systems which involve the fixing of tariffs for renewable energy by governmental intervention, are regarded as producing more efficient outcomes. The use of the REFIT system in Germany is associated with an institutional tradition that places emphasis on giving competitive opportunities to new market entrants in order to break up concentrations of market power by incumbents.     

Nitrogen isotopes in the recent solar wind from the analysis of Genesis targets: Evidence for large scale isotope heterogeneity in the early solar system

We have analyzed nitrogen, neon and argon abundances and isotopic ratios in target material exposed in space for 27 months to solar wind (SW) irradiation during the Genesis mission. SW ions were extracted by sequential UV (193 nm) laser ablation of gold-plated material, purified separately in a dedicated line, and analyzed by gas source static mass spectrometry. We analyzed gold-covered stainless steel pieces from the Concentrator, a device that concentrated SW ions by a factor of up to 50. Despite extensive terrestrial N contamination, we could identify a non-terrestrial, ¹⁵N-depleted nitrogen end-member that points to a 40% depletion of ¹⁵N in solar-wind N relative to inner planets and meteorites, and define a composition for the present-day Sun (¹⁵N/¹⁴N = [2.26 ± 0.67] × 10⁻³, 2σ), which is indistinguishable from that of Jupiter’s atmosphere. These results indicate that the isotopic composition of nitrogen in the outer convective zone of the Sun has not changed through time, and is representative of the protosolar nebula. Large ¹⁵N enrichments due to e.g., irradiation, low temperature isotopic exchange, or contributions from ¹⁵N-rich presolar components, are therefore required to account for inner planet values.     

An evaluation of the use of renewable energy to pump water in Sacala las Lomas,Guatemala

An evaluation has been conducted to establish if using renewable energy is technically and economically feasible to pump water in Sacala las Lomas, Guatemala. A deep groundwater well has been proposed and a multi-stage pump system is being considered to distribute groundwater to users’ homes. A weather station was erected in Sacala to collect site-specific data. Wind velocity, wind direction, solar insolation, temperature, precipitation, and barometric pressure data were collected over a 1-year study period. The analysis of the data indicated that the potential power generated by a photovoltaic array or wind turbine would be insufficient to economically pump water to the village under current conditions. Although there may be reasons other than economics that make the potential renewable energy applications attractive, the space and maintenance required to install and operate a sufficient off-grid system outweigh the benefits. A grid-intertie system would allow any number of solar panels to be used in the system while still providing the electricity demand using grid-power.