Energy sources sustainable

If for example Ti02, is used to capture sunlight in a photo-catalytic reaction then only about 10% of the available spectrum will be of use, since it requires 3.2 eV to create an electron-hole pair in Ti02. Both the photovoltaic and the photochemical methods are of potential interest, but at present they are too expensive. Also, the production of semiconductors used in photovoltaic cells consumes much energy. Nevertheless, the prospect remains attractive. If cells could be made with an efficiency of say 10 % then only 0.1 % of the earths surface would be required to supply our present energy consumption  

Other long-term alternatives representing sustainable forms of energy such as waves at sea can be utilized but are even further from a stage where exploitation is economically feasible. 

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Over 80 percent of the world s energy consumption comes from nonrenewable sources that cannot be sustained indefinitely under current practices. If technological advances continue to make conventional energy resources plentiful and affordable for many years to come, the transition to more sustainable energy sources can be smooth and minimally disruptive. 

A major problem with the new sustainable energy sources is their reliability. Inherently they will produce electricity as the wind blows and the sun shines. The need for power is not constant either, with peak demands during the day. Hence, ways are needed to store energy that enable release on demand. Synthetic fuels and methanol are candidates, but the most important will be hydrogen. It can be produced conveniently from water and electricity with a reasonably high efficiency of 70 %. Hydrogen is the ideal fuel for fuel cells. 

What Are Sustainable Energy Sources think about possible energy sources, the enormous energy wealth at the heart of our solar system demands our... 

Was this your answer A sustainable energy source is an energy source that has the potential for being available indefinitely The technologies that take advantage of these sources should be environmentally benign. 

Why is it in a country s best national security interests to invest in sustainable energy sources ... 

Complete with the keys to a quantification of process efficiency and sustainability, this cutting-edge resource is the ideal guide for those engaged in the transition from fossil-based fuels to renewable and sustainable energy sources using low-waste procedures. 

Minimize depletion of natural resources. [This principle resonates in many existing lists of principles. It reminds the engineer of the need to reduce and recycle the materials used in production and consumption systems. Conserve energy and improve the energy of internal operations and of the goods and services. Make every effort to use environmentally safe and sustainable energy sources.]... 

Summarized the current energy challenges, such as carbon emissions, population growth, and cost, and presented opportunities to address these challenges, such as developing sustainable energy sources. 

The transportation sector is clearly the sector where a transition to sustainable energy sources is most difficult. For the past several decades, hopes were placed in battery-based electric vehicles, but it has taken long time to reach the technical goals for battery performance, and the economic goals that would make a purely battery-operated vehicle with suitable range become economically acceptable have not yet been reached. As a consequence, automobile manufacturers have lowered the expectations to battery-driven vehicles and instead hope that fuel cell vehicles will be able to meet both technical and cost goals. The analysis in Chapter 4 indicates that this may not be the best approach, because fuel cell-battery hybrids may well turn out to be a better solution, due to the complementary advantages of the two sys-... 

An example of a renewable energy source is one derived from plant materials, such as wood or grain. Plants can be regrown to replace those used for energy. However, plants are sustainable energy sources only if they can be replaced as quickly as they are used. In many areas of the world, trees are being cut for lumber or fuel at a much faster pace than they can be regrown. Such practices are not sustainable. 

Ethanol is being hailed as the fuel of the future. Interest in the production of fuel ethanol from renewable sources has increased significantly. For fuel ethanol production to become a practical reality, cheaper substrates and more efficient production processes are needed [1,2]. Biomass, which includes all plant and plant-derived material, forms a potential renewable source of sugars that can be fermented to produce fuel ethanol and a variety of other fuels and chemicals. In addition to the many benefits common to renewable energy, biomass is particularly attractive because it is currently the only renewable sustainable energy source for liquid transportation fuel. 

A sustainable energy source is one that will meet the needs of the human race on an indefinite basis without causing long-term damage to the environment. This concept is termed sustainability . Various definitions of sustainability exist in the literature, but they all convey the same message. 

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