a r t i c l e i n f o The electric power industry is restructuring as regulations move from states to regional and national levels. Estimates of regional fuel and input substitution are essential for practitioners and policy makers. This paper estimates substitution under static and dynamic scenarios, examining changes in technology and total factor productivity from 2001 to 2008. Two-stage est...

A fuel cell can be thought of as a cold-combustion power source that generates electrical energy directly from (stored) chemical energy. Due to minimal heat transfers, it is unfettered by conversion-efficiency limitations characteristic of hot-combustion devices. Unlike batteries, but similar to internal combustion engines, a fuel cell is a continuous-flow system in which fuel and oxidant are e...

Base station sites (BSSs) powered with renewable energy sources have gained the attention of cellular operators during the last few years. This is because such “green” BSSs impose significant reductions in the operational expenditures (OPEX) of telecom operators due to the possibility of on-site renewable energy harvesting. In this paper, the green BSSs power supply system parameters detected t...

physiologically thermal comfort condition is a limit of temperature and humidity. ,in which thermal control mechanism of human body is in its least activity . thermal comfort conditions not only have impact on sizes of heating and cooling equipment ,but also affects the thickness of insulation, and .energy, consumption of buildings. it is necessary to define thermal comfort condition for differ...

Non-road diesel engines are significant contributors to air pollution in the United States (USEPA, 2004). These engines emit particulate matter (PM), nitrogen oxides (NOx), sulfur dioxide (SO2), and other pollutants. The Clean Air Non-road Diesel Rule was put in place to reduce emission levels from agricultural, construction, and industrial diesel powered equipment. This rule calls for a reduct...

Energy consumption in Iran is a subject of debate. Some may think that oil is cheap in Iran and thus no need for this kind of research. This simple minding is erroneous first because Iran subsidizes billion dollars each year for the imported diesel fuel specially for agricultural use and second because energy studies reveal the degree of professionally using the technology. We can easily find t...

Energy efficiency and alternative power play a big role in sustainability The use of fossil fuels as a major energy source has given rise to several concerns such as the effect of harmful emissions and sustainability. Due to these reasons lot of efforts have been placed on finding alternative energy sources. One of the promising environmentally benign alternative for large scale electricity pro...

This paper describes simulation results of a small 500 W wind fuel cell hybrid energy system. The system consists of a Southwest Wind Power Inc. AIR 403 wind turbine, a Proton Exchange Membrane Fuel Cell (PEMFC) and an electrolyzer. Dynamic modeling of various components of this small isolated system is presented. Simulink is used for the dynamic simulation of this nonlinear 48 V hybrid energy ...