ENERGY ECONOMICS REVIEW
Year:2008 | Volume:5 | Issue:18|Papers Count:10

Taking into account rising demand for natural gas and the increasing share of gas in global energy supply in recent decades and the need for maximizing value added of the sector rather than selling raw gas for Iran as the country with the second most important natural gas reserves, it is important to look into use of modern technologies in this industry in Iran. Given the importance of economic cost benefit analysis, before undertaking any project including use of new technologies, this paper studies the techno-economic feasibility of converting natural gas to liquids (GTL) using the cost-benefit analysis approach and Excel software. We use sensitivity analysis to identify the main factors that affect economic viability of natural gas to liquid products. The results show that GTL conversion is feasible and that reductions in needed capital investments, increasing crude oil prices and access to cheaper feed gas can increase the profitability of the process.

This study designs a hybrid micro turbine-photovoltaic generation system, using DC/AC converters to supply electric power and heat energy of urban buildings. In order to minimize costs the study has to take into account as dependent variables the investment costs the hybrid system, environmental pollutants, peakload reduction{paykzedaie} and buying and selling of electricity from and to the national grid. In view of the large number of variables and the complexityof the objective function, we use Particle Swarm Optimization (PSO) algorithm to solve the optimization problem. The hybrid system has 100 variables which relate to the definition of optimal capacity of micro-turbines, photovoltaic panels, inverters, and installation angles of photovoltaic panels and how to optimize the productivity of the system over 24 hours in different seasons. The optimalization problem is solved using software developed using the MATLAB programming context. The results show that for a hospital with a peak electricity load of 340 kws and energy load of 870 kW, so long as the rate applied for electricity and peak load reduction( the subsidy paid by the government for each KW os hybrid system) is above $1000 per KW, the project will have a total return of $64,361 over its lifetime. The optimal capacity of micro-turbines and inverters to be used are respectively 349 and 315 kW.

Oil price fluctuations and their impact on Economic growth have become major subjects of study by researchers following the oil crises of 1970s and more recent sharp fluctuations. This article studies the  long term relationship between oil prices and Economic growth in Iran, using seasonal data for the period 1989-2007, by using asymmetric cointegration  to analyse the asymmetric cointegration between these two variables. The study shows that in Iran, as an oil exporting country, the oil price fluctuations have an asymmetric impact on growth, meaning declining prices have greater impact on GDP than rising prices.

In this paper، the wavelet transform and neural networks are used to produce more reliable forecasts of crude oil prices. In this combined model, we use the wavelet transform to minimize the noise present in the data and then apply artificial neural networks to the smoothed data to forecast oil prices. Comparing the RMSEs of alternative models with the combined model confirms that reducing the noise and smoothing the data produces more reliable predictions of crude oil prices.

The prevailing method of natural gas pricing assumes that it has a close relationship with crude oil price and follows its gyrations. Due to this, for many years the price of natural gas has been taken as a function of oil prices. Analysis of historical trends of oil and gas prices in regional markets also shows that these two variables are closely correlated. This study tries to explain the above relationship by using econometrics methods and examining the stability of this long term relationship. To this end, after referring to some common rules of thumb for estimating gas prices through a simple regression, the hypothesis that a simple regression is able to produce an efficient and unbiased estimate of gas prices is examined. The study concludes by offering an Error Correction Model that can produce efficient estimations of the long term relationship between oil and gas prices.     

These days there is a preference for clean, renewable energies that are low cost, due to concerns about political and economic crises, limited availability of fossil fuels, environmental concerns, economic growth, intensity of consumption and other factors. Unfortunately no single source of energy can supply all energy needs and hence there is a need to look at the best combination of different sources. How to decide on the optimal combination of different sources of energy has thus become a major concern of most countries. Energy policy issues have to contend with contradictory economic, social and environmental objectives and thus need to use methods that can allow simultaneous treatment of various factors. The analytic network process is one of the multi-variate decision making systems that can take into account relationships and contradictions amongst different objectives and alternatives. The use of the ANP method to estimate the optimal combination of energy sources in Iran assigns the highest priority to natural gas and the least priority to petrol and solar energy, while showing the need for an increase in the share of renewable energies in the country’s energy system.

When in contractual systems an International Oil Company’s fees are paid as a specified share of the production this is called a Production Sharing agreement. The most important economic variables in production sharing contracts are royalty, cost oil, distribution of profit oil and tax on profit. This paper studies the impact of these variables on optimal oil production. This study shows that cost oil has the greatest impact on oil production. The impact of other variables depends on the value of the variable compared to the values of remaining variables. This study shows that increasing the share of international oil companies from revenue of oil field production encourages them to invest on secondary recovery.

Energy intensity index, at micro level is used commonly to show efficiency of production systems, as well as, at macro level to show country’s energy efficiency. However, this index is affected by several opposite causes that make comparative analysis too hard. This paper besides introducing most energy intensity causes, based on OLS method estimates a multivariable model to analyze each cause's effect. Results show that the size of service sector (representing structural change) has significant effect on reducing energy intensity. Square of countries, consistent with theory, has positive significant effect and a size of one forth of service sector effect. Estimating of elasticity effects shows that one percent change (rising) of service sector size, cause one half percent change (declining) of energy intensity. Square's elasticity coefficient also consists with theory's expectation and has shown significant effect.