The next time you hear an airplane flying overhead, look up, and pause for a moment. What you see is a machine that is heavier than air, but which is somehow being sustained in the air. This is due to the airflow over the airplane. This airflow exerts a lift force which counteracts the weight of the airplane and sustains it in the air—a good thing. The airflow also exerts a aerodynamic drag force on the airplane which retards its motion—a bad thing. The drag must be counteracted by the thrust of the engine in order to keep the airplane going. The production of thrust by the engine consumes energy. Hence, the energy efficiency of the airplane is intimately related to aerodynamic drag. This is just one of many examples where the disciplines of aerodynamics and energy interact. (more…)
One of the most important aerodynamic effects on energy consumption required to keep a body moving through a fluid is the aerodynam ...
If water is put on the floor on a cleaning operation, it tends to dry rapidly after a short time. In this position, we say that ...
In contrast to electromagnetic suspension systems, electrodynamic suspension systems can provide stable suspension without a feedba ...
The comfort heating system in a building brings itself to the concept of complete heating operating unit. In order to work prop ...
Oceanic heat flow data show a clear variation with the age of the lithosphere. Values greater than 100 mW m –2 occur near the r ...
Different lasers use different materials as the active medium. The medium can be either solid, liquid, or gas, and there are advantages for each in the amount of energy that can be stored, ease of handling and storage, secondary safety hazards, cooling properties, and physical characteristics of the laser output. (more…)
There are literally thousands of uses for lasers. One of the largest applications is telecommunications—sending a signal throug ...
The word “laser” is an acronym for “light amplification by the stimulated emission of radiation.” Lasers of all kinds consist o ...
The first known laser was made by Theodore Maiman at Hughes Research Laboratories in Malibu, California, in 1960, but the seeds ...
Several molecular systems have been constructed that mimic various aspects of photosynthesis. Two of these utilize molecular system ...
It is known that laser printers print faster, but swallow a large amount of energy, even if the printer is in the energy saving ...
Approximately 40% of Earth’s population is ‘‘off the grid,’’ mainly in developing countries. Wireless power transmission envisioned by Nikola Tesla a century ago is feasible today. Microwave beams can propagate power efficiently along lines-of-sight over long distances. Orbiting microwave reflectors could form the basis of a global electric grid.
An advanced technology path to electrification is the solar power satellite (SPS) proposed by Peter Glaser. Solar flux is about 10 times higher in space outside Earth’s shadow cone than the long- term average at the surface of spinning, cloudy Earth, and power from space can be beamed by microwave efficiently through cloudy skies to the surface where it is needed. (more…)
Advanced technology global electrical grids may be more promising for renewables energy. With current transmission lines, even if c ...
So you're finally tired of those exorbitant electricity bills, or, you're catching onto a "greener" way of life. Either way, solar ...
In today's tough economic times and with the increasing prices of gas and oil, finding alternative sources of energy should be ...
So-called thin-film photovoltaic devices are usually based on mixtures of elements other than silicon — most notably copper ind ...
The Home Solar Power System made its debut about two decades ago and has since flourished with the many advertisements touting ...
Silicon is the material of choice for most Micro Electro Mechanical Systems due to (1) the feature size often being in the range of less than 20 mm requiring single crystalline material and (2) the dependence on fabrication techniques developed by the electronics industry for processing this material. However, it is a particularly poor choice for the larger thermally based devices that characterize Microtechnology-Based Energy and Chemical Systems. The room temperature thermal conductivity of silicon is approximately 150 (W/mK). Use of this material leads to high rates of heat transmission across the short distances where temperature gradients occur. The thermal conductivity of silicon above 10001C falls to below 25 W/mK, but the average value can still be high. (more…)
Fabrication techniques developed for integrated circuit (IC) production have been refined to the extent of supporting a multi-b ...
n fabricating microscale energy systems, a number of operating conditions must first be taken into account. Foremost are the op ...
Micro technology can be employed to produce miniaturized refrigeration and cryocooling systems. Although process intensificat ...
Many characteristics of traditional engines make them attractive for use in power generation and propulsion technology. They tend t ...
So-called thin-film photovoltaic devices are usually based on mixtures of elements other than silicon — most notably copper ind ...
The convention aims not only at stabilizing CO2 emissions in developed countries but also at ultimately reducing man-made CO2 emissions globally so as to stabilize the global climate. Environmental degradation cannot be singled out as an independent matter among various global issues. (more…)
Biomass has been a main energy sources in the world since the beginning of civilization. It has been important in development p ...
Over the last decade, the number of countries researching the potential of biomass and bioenergy for energy services rose rapid ...
Renewable energy sources cannot run out and causes so little damage to the environment that its use does not need to be restric ...
Estimation of the future technical potential of biomass as an energy source is dependent on assumptions with respect to land av ...
Climate change caused by the enhanced greenhouse effect is one of the most significant global environmental issues. Increased emiss ...
The comfort heating system in a building brings itself to the concept of complete heating operating unit. In order to work properly, a heating system must utilize in different of serving pieces and function. This includes such as control function, energy source, a load device, and something that will indicate or record the level of heat energy produced. (more…)
If a space is occupied on a predictable schedule, you can use either timeclocks or setback thermostats to turn the conditioning ...
Heat has a enormous influence in our daily lives. Heat quantity exposed in our live has related to the foods we eat, the temper ...
HVAC (heating, ventilation, and air-conditioning) systems vary depending on the complexity of room units size from single rooms ...
Steam heating is an absolutely wonderful method to heat your home. Steam heat is always driven by steam produced from water in ...
Active solar hot water systems water are usable with air, liquid, vapor or liquid collector fluid or gas to liquid process. Hot ...
Extensive insulation repairs are usually done by contractors having the specific skills and equipment appropriate to the type of insulation being installed. Experience indicates that some insulation methods are much better than others, particularly for buried pipe.
Become familiar with the advantages and disadvantages of all the insulation methods before initiating the work. (more…)
Visual inspection is usually good enough for under roof insulation that is accessible, as in boiler rooms, pipe chases, and ste ...
Insulation is what keeps the heat energy of a boiler system from leaking out of the system on its way to the end users. Inspect ...
Imprinted on every batt or blanket of insulation or on every bag of loose insulation is its R-Value. The higher Insulation R-Value, ...
In many existing buildings, the only economical way to improve the thermal resistance of the roof is by having insulation insta ...
If water is put on the floor on a cleaning operation, it tends to dry rapidly after a short time. In this position, we say that ...
Heat has a enormous influence in our daily lives. Heat quantity exposed in our live has related to the foods we eat, the temperature changes of our house and buildings, and clothes we wear. Heat can be transferred between different objects with different temperature. But do you know that heat is different from temperature? (more…)
The comfort heating system in a building brings itself to the concept of complete heating operating unit. In order to work prop ...
As a result of high and rising costs of fossil fuels and fossil fuels affect global environment concern , and by the reduction ...
In these regenerators the heat energy transfer between primary and secondary fluid is primarily by radiation and its installati ...
Active solar hot water systems water are usable with air, liquid, vapor or liquid collector fluid or gas to liquid process. Hot ...
Energy exists in many forms. Some of energy forms are simple to use and identify as energy. But other forms of energy can not b ...