After power stations, transportation section, especially road traffic, is known as the most important cause of climate change. In the transportation literature these costs, known as the external costs, are not paid by people who cause them. Conversely, based on the economic welfare theory, any cost that takes place in society must be paid by people who cause it. So these costs must be recognized to be converted into the monetary value. The values, then, must be taken by charges or other ways taxes. In Iran, there is no research that relates to the issue of external cost of climate change. Therefore, there is no monetary value of climate change costs due to road transportation in Iran yet. In this paper, this research gap is considered and a mathematical model is used to estimate the mentioned costs. The results are obtained for different vehicles in road transportation including car, mini bus, bus, truck and other vehicles. The model is run for freeways in Iran. The results of the model indicate that external costs of global warming are 10.3, 31.3, 94, 94 and 135.8 Rials for 1 Km mileage of each passenger car & pickup, mini bus & light truck, two and three axle trucks, bus and heavy trucks, respectively. Annual external cost of CO2 emission in freeways is also approximately 360 billion Rials, 30% of which is the contribution of heavy trucks, passenger cars & pickup take the second place with the share of 25%. The results of this paper can certainly help the policymakers to make good, precise and fair decisions related to the charges of road transportation. Road transportation, primarily, due to its unique characteristics have a special position among various transportation modes. Road transportation is the most available and easy to use mode of transport in Iran. But the transportation has negative impacts too. Road transportation activity imposes external costs such as air pollution costs, noise costs, climate change costs and etc. What should be considered in external costs is that the contribution of the road transport, as international studies show, is around 92% of total external costs of the transport sector. Climate change or global warming is one of the major threats to humanity in the 21th century. After energy section, transportation section especially road transportation, is known as the most important cause of climate change. In the transportation literature these costs, known as the external costs, are not paid by people who cause them. Conversely, based on the economic welfare theory, any cost that takes place in society must be paid by people who cause it. These costs cause loss of a considerable amount of public resources. For example, the external costs for 17 European countries for year 1995 have been around 975 billion dollars. This costs has been estimated around 600 billion dollars for US in 1989. So, these costs must be recognized to be converted into monetary value and then these costs must be taken by charges or other ways of road pricing. This paper is based on a theoretical-practical research which deals with one of the major challenges of the present transportation by employing quantitative techniques and statistical and econometrics models. In Iran, there is no research that relates to an issue of external cost of climate change. Therefore, there is no monetary value of climate change costs in Iran yet. Unfortunately, the government is not attentive to external costs; although the topic has been highlighted in recent years and some studies have been conducted regarding the subject. Yet, these costs are not considered in economical transactions. In this paper, this research gap is considered and a mathematical model is used to estimate the costs of climate change. The results are obtained for different vehicles in road transportation including passenger car and pickup, mini bus, bus, two and three axles truck and heavy truck. The model is run for Expressways in Iran and results are demonstrated. Estimation of some of the parameters existing in the model would take a long time and require a much budget. So, these parameters were extracted from the literature. To estimate the global warming costs, a simple model from GRACE project has been adopted. Table 1 shows more details of the mentioned model. The required data for this model has been prepared. These data items include price of 1 tone of Co2, amount of Co2 released by each vehicle type and amount of Co2 released from fuel production. External costs of global warming are estimated for expressway network of Iran based on the model presented in previous paragraph and in Table 1. The first step of this phase is to select a representative sample of Iran's expressways. Totally 13 expressways were selected. It was tried to select a sample representative of Iran’s expressway network to facilitate generalization of the results. In the next step, a lot of information regarding the selected roads (including length of road, daily traffic volume, statistics of vehicle types, and etc.) from different data sources has been collected, aiming at using this information in appropriately in the model. In addition, vehicles have been classified in five main classes. After gathering the required information, the model was employed and the external costs of global warming have been estimated corresponding to different types of vehicles. Discussion and The values in above table have a straightforward interpretation. As an example, a user of passenger car or a pickup must pay 10.3 Rials passing 1 KM of expressway as a compensation of global warming external costs. This value is 135.8 and 94 for heavy trucks and buses, respectively. The results indicate that annual external cost of co2 emission in Expressways is approximately 360 billion Rials, 30% of which is the contribution of heavy trucks with more than 3 axles followed by passenger cars and pickups with the share of 25%. The considerable amount of these external costs is a good index to realize the importance of external costs of Iran’s road transport. It should be noted that these costs are different from many non-monetary effects which external costs impose to society. This involves careful attention of governors and macro-level decision makers to external costs and their issues to provide appropriate solutions to reduce or internalize these costs. It should be noted that the main and most important solution to reduce and manage external costs is road pricing and charging road users. The experience of this solution in the world has shown that besides reducing external costs, a considerable financial resources is gathered from user charging, which can be used in more transportation infrastructure developments. The results of this paper can certainly help the policymakers to make good, precise and fair decisions related to the charges of road transportation.

Generation of electricity releases various types of pollutants, which cause damages to a wide range of receptors such as human health, natural ecosystems, crops, and building materials. When the cost of such damages is not accounted in the price of electricity, they are referred as external costs. The estimation of external cost has important usage in policy making. An external cost, also known as an externality, arises when the social or economic activities of one group of people have an impact on another group, and that impact is not fully accounted, or compensated for, by the first group. Thus, a power station that generates emissions of SO2, causing damage to building materials or human health, imposes an external cost. Because the generator of the electricity when deciding on the level of the activities does not take into account the impact of these activities on the buildings’ owners or on those who suffer health damage. In this example, the environmental costs are “external” because, although they are real costs to the members of the society, the owner of the power station is not taking them into account when making decisions. The economic value is a measure of the benefit provided by an action or service to an economic agent. It is generally measured relative to units of currency, and the interpretation is, therefore "what is the maximum amount of money that a specific actor is willing and able to pay for the good or service"? .In this paper, we calculated the economic value of power generation efficiency improvement. The results show the economic value of one percent increase in power generation efficiency is equal to 294 million dollars

In this study, a model for measuring the effects and the physical-economic consequences of air pollutants emitted from Power Plants on urban buildings facades was developed. For the case study, the effect of SO2 pollutant emitted from Rajaee Combined-cycle Power Plant on Qazvin’s buildings’ facades was studied.

To develop this model, the Gaussian plume method was used to estimate the air pollution dispersion and impact pathway assessment (IPA) to calculate the air pollutant external costs. The damage costs of SO2 due to the corrosion of building materials, soiling, and consequently an increase in cleaning expenses of each square meter of urban buildings’ facades were localized. After the validation of the output results of the developed model, the external costs based on the wind speed and different atmospheric stability classification were estimated. Different atmospheric stability classes were examined using the Pasquil-Gifford (P-G) classification.

Based on the facade’s material, the highest external costs were related to the white cement with 36575 dollars (849 million Rials). For the thatch façade, which is the local material of the region, the external cost was estimated to be 5376 dollars (1247 million Rials). Based on the wind speed, the highest external cost was obtained for the wind 1m/s with 139026 dollars (3254 million Rials) and the lowest cost was 352 dollars (82 million Rials) for the wind speed of 20 m/s. For the atmospheric stability classification, the lowest external cost in extremely unstable class (A) and the highest external cost in neutral class (D) have been measured. The external cost due to the SO2 pollutants for the city of Qazvin was 0.009 dollars (2162 Rials) For each megawatt-hour generated electricity.

The results showed that the materials compatible with the local region can have lower external costs compared with the new materials used in the buildings.

In the past, power generation expansion planning was mainly based on a cost minimization target subject to acceptable level of system reliability. Nowadays, environmental considerations have changed into important planning priorities increasing the capacity expansion costs. Socially, this increase is compensated by the reduction in external costs caused by lower levels of emissions. In this paper, emission constraints have been imposed on generation capacity expansion planning of a grid much the same as Iran power grid for the period of 2005-2023 using WASP package. Changes in system expansion costs have been compared with changes in environmental damage costs. According to the results, in long term the increase in capacity expansion cost caused by imposing emissions constraints is compensated with reduction of external costs of emissions.

Annually, traffic accidents will destroy the GNP or GDP. Developing countries according to the specific problems of these countries have been wasting more than developed countries. In this paper had been goal the estimating of the mean of costs of the death related to road crashes using anticipate the numbers of the future dead. Initially, for reason, using by time series and ARIMA pattern the overall number of dead in 2012 year with 5percent confidence estimated about 19996s person then calculated the value of the statistical life nearly 903 million Rails with use the court award method and external cost of death counted about 18056388. The GNP in this year estimated about 5277017 milliard Rails. Eventually, it estimated about 0.344 percent the portion of the costs from deaths to GNP.

In this study, external costs due to air pollution in the city of Tehran are estimated for CO2, SO2, NOXand PM pollutants in 1390. In the first step, employing up to down procedure, these pollutants’ emission from oil products, liquid gas and natural gas fuel from transportation, industrial, household and commercial, army and departments, plants and refineries are estimated. Then the external costs due to these emissions have been computed based on presented Expenditure in universal bank and Iran’s environment organization report at 1381. The results show that external costs due to four mentioned air pollutants are approximately 18/06 thousand billion Rials (based on constant prices in 1981) in Tehran city in 1390. The maximum external costs are 83 percent for PM pollutant, 94 percent for transportation and 72 percent for gasoil fuel from point of views of pollutants type, pollutants producing section and the type of fuel consumed, respectively. Also, the total air pollution external costs due to these four pollutants are 0.18 and 0.71 percent with respect to Gross Domestic Production (GDP) of Iran and Tehran,respectively. In this study, realization of external costs is done under the light of Cost Plus method by inflation andexchange rates. In the first approach, external costs are estimated to be 24.88 thousand billiard Rials and in the second approach, they are found to be approximately 66.74 thousand billiard Rials.

The subject of air pollution has become important since the emergence of industrial societies. Based on statistics provided by the spokesman of the Ministry of Health and Medical Education on December 8, 2017, in Iran, due to air pollution, 2.48 percent of gross national product is wasted. Also, the amount of damage caused to the national economy caused by air pollution is 34 trillion tomans. Annually, $ 25 billion of the world's economy becomes smoke and goes to the air, due to air pollution. Meanwhile, metropolitan areas have a very significant contribution to this damage. According to the Economic Welfare Theory, any costs that are incurred in society must be paid by the causing factors. Today, in most countries in the world, external costs are estimated and included in the pricing calculations. Therefore, it is important to calculate the external costs of air pollution in codification of an appropriate management approach. For this purpose, the aim of this research is to consider an economic, engineering and management approach to external costs caused by the emission of PM, NOx, SO2, CO pollutants in order to plan and provide targeted solutions for reducing air pollution in Karaj.

Traffic accidents are one of the very important factors of mortality and morbidity and is severely threatened human society by the severe effects of social, cultural and economic. The damage was more severe in developing countries, such as Iran and therefore the number and severity of accidents in these countries is several times higher compared with developed countries. Basically, the cost of accidents consist of two main parts: internal and external costs that external costs consist of the price of human lives and economic impacts of disabilities and mental injuries. In this study, according to collecting the statistics of death, injury and damage accidents of region 2 roads in Tehran city in 1393, part of the external costs include the cost of death and disability is estimated. To quantify the effects of the accident on human health and mortality, is used the DALY indicator that this indicator is used for assessment of human health (with the economic perspective of cost-benefit) and is unique quantitative indicator that is used for assess the external cost of death, desease or disability and is representative of the adjusted life year due to premature death to disability. Also in this study, it is tried first, separately collecting the statistics of accidents of region 2 roads in Tehran city then the roads have death accidents isolated and disability Adjusted Life Year (DALY indicator) has to be calculated for roads that have death accidents.

Many reports that appeared during the last 20 years have shown that atmospheric pollution causes serious damage to human health and to environment. Electricity generation from fuel fossil is one of the major sources of pollution and considerable share of this damage. The price of electricity in Iran, as in many other countries also, includes only the production of private costs and ignores any other external economic effects. In this research, the external costs of SO2 and NO2 emissions have been calculated for Shahid Rajaii Power Plant. Shahid Rajaii Power Plant is located at Tehran – Gavin free way. The system of Shahid Rajaii almost depends upon fuel oil, gas oil and natural gas. It's total capacity is almost 2000 MW. The system is based on fire Power Plant which consists of 13 units. There are 4 steam turbines with 1000 MW capacity, 6 gas turbines with 640 MW and 3 steam units with 375 MW. In this paper, the external costs have been accounted for unit steam of power plant. The SO2 and NO2 emissions were compared with international standard of ambient air on four seasons, and in two conditions of Normal and Maximum load. The resulting external costs of SO2 and NO2 emissions were achieved about 444.226, 276.069 Ris/kWh.The results shows that the external costs of SO2 emission is highest due to high usage of fuel oil.