The outlook for reductions in future energy use is necessarily based on the potential for increased technological and operational efficiencies. In this section, the outlook for such improvements in large commercial aircraft over the next quarter century is examined.
Engine efficiencies may be improved by between 10 and 30% with further emphasis on moving more mass through engines that operate at higher temperatures and higher pressures. A continuation of the historical trend would lead to a 10% increase in L/D by 2025, and further improvements in the reduction of parasitic drag may extend these savings to perhaps 25%. However, the technologies associated with these improvements have weight and noise constraints that may make their use difficult. (more…)
As a reaction to these historical perspectives, the building industry has witnessed a certain rise in design responses to regional climatic conditions, as part of a powerful efficiency and energy conservation push since the 1970s. More recently, the zero green house gas emsission and office building has become a design concept as part of strategies to introduce urban renewable energy as an increasing contributor to managing urban energy supplies. (more…)
Hydrogen has many applications when it comes to fuel. It can be used both in internal combustion engines and hydrogen fuel cells. Hydrogen engines are using the same principle the same way as gasoline fuels or hydrogen natural gas burned combustion, while the chemical energy of hydrogen used to generate electricity and heat transmission. Since the electrochemical reactions produced more efficient energy compare to the combustion energy, fuel cells are created more efficient fuel compare to internal combustion engines. In the long term it will benefit to the more efficient hydrogen conversion process. (more…)
All of today’s hydrogen conversion products, demonstration models, and prototypes possess some deficiencies; they cannot yet provide, at an affordable cost, the level and quality of energy services, and hydrogen delivery system demanded by a broad base of consumers. While fuel cell technologies have generated much excitement, they are still in various stages of maturity. Most have not been manufactured in large quantities and numerous performance issues—including durability, (more…)
