ARTICLES
Permintaan Bahan Bakar

Permintaan BBM meningkat terus karena pertambahan penduduk dan lajunya kemajuan teknologi semua sektor. Selain itu, permintaan industri kimia dunia melaju secara eksponensial yang luar biasa tinggi percepatannya. Demikian juga permintaan untuk industri reforming untuk pembuatan Hidrogen. Sementara itu, minyak fosil semakin habis dan jenis bahan bakar ini tergolong tidak terbarukan. Dengan hukum permintaan dan tarik menarik, biaya semua kegiatan multi sektoral termasuk pengadaan BBA dan pengadaan semua teknologi terutama transportasi naik. Praktis semakin lama kekuatan transportasi Indonesia untuk mendukung semua aktivitas berkurang. Untuk mengatasinya dilakukan pendekatan ulang melalui Roadmap ketahanan Energi transportasi Indonesia yang di undang undangkan untuk menjamin ketersediaan energi. Metoda Technology Roadmap sebagai alat stratejik dalam peramalan teknologi untuk mengidentifikasi teknologi dan kebijakan kunci yang harus dibuat dan langkah langkah yang harus dilakukan menerapkan teknologi setiap waktu. Dalam Roadmap tersebut ada tahapan jangka pendek menengah dan panjang pengurangan penggunaan BBM dengan BBAN dan pengurangan BBAN dengan Hidrogen. Pada waktu yang sama pengurangan LPG dengan Hidogen dan pada tahun 2025 transportasi menggunakan Hidrogen.

Professor Channing Robertson of the Stanford University Chemical Engineering department gives an introductory lecture, outline, and background for the course.

Introduction to Chemical Engineering (E20) is an introductory course offered by the Stanford University Engineering Department. It provides a basic overview of the chemical engineering field today and delves into the applications of chemical engineering.

Stanford Chemical Engineering Department:
http://cheme.stanford.edu/

In general, the physical and chemical properties and the performance of ethyl esters are comparable to those of the methyl esters. Methyl and ethyl esters have almost the same heat content. The viscosities of the ethyl esters are slightly higher, and the cloud and pour points are slightly lower, than those of the methyl esters. Engine tests demonstrated that methyl esters produced slightly higher power and torque than ethyl esters. Some desirable attributes of the ethyl esters over methyl esters are: significantly lower smoke opacity, lower exhaust temperatures and lower pour point. The ethyl esters tended to have more injector coking than the methyl esters. Several studies show biodiesel can run in a conventional diesel engine for an extended time. Researchers in several states including Missouri and Idaho, have run diesel engines in pickups, city buses, large trucks and tractors on various mixes of biodiesel/diesel fuel. These mixtures have ranged from 2/98% (B2), 20/80% (B20) up to 100%(B100). Standard diesel engines will operate on 100% biodiesel. In cold weather, biodiesel begins to cloud
and thicken at about 272 K. Biodiesel thickens at warmer temperatures than No. 2 diesel fuel, but additives are available that will lower the pour point. Pour point is the point at which flow of the fuel ceases. Mixing biodiesel with No. 1 diesel as is currently done with No. 2 will lower the pour point. Installing an in-tank or fuel line heater may also be needed to keep the fuel flowing in cold weather. A blend of biodiesel/diesel fuel has a lower pour point than 100% biodiesel, but gelling may still occur unless care as mentioned earlier is taken.

Fuel Cells

Author: David Tanguay

Fuel cells are simple devices, containing no moving parts and only four functional component elements: cathode, electrolyte, anode and interconnect. Fuel cells are actually being used more widely than many people think.


Fuel cells are electrochemical devices similar to batteries that directly convert chemical energy of a fuel into electrical energy and heat. They are {readmore}different from batteries in that they consume reactant, which must be replenished, while batteries store electrical energy chemically in a closed system.

Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, rural locations, and in certain military applications where conventional power may be difficult to obtain.

Although fuel cells are usually classified by their operating temperature and the type of electrolyte they use, they are not constrained by the maximum Carnot cycle efficiency as combustion engines are, because they do not operate with a thermal cycle.

There are many benefits to fuel cells, first, they are not dependent on dwindling oil supplies, running instead on hydrogen, the most abundant element in the universe, and second, fuel cells are much less polluting and about twice as efficient as typical steam-turbine electricity production. They are an extremely clean source of power because they combine hydrogen and oxygen the two elements that make up water, the main byproduct.

Fuel cells are no longer tomorrow’s technology, the stuff of science fiction and space travel. They are used in many different applications that may not seem like a significant achievement, however the ways in which they can be used are growing every day.

Fuel cells are proof that there are smart, safe, and clean alternative power sources. It is proof that we can be self sustaining and that dependence on fossil fuels will one day soon be obsolete. Fuel cells have been referred to as continuous batteries when they are supplied with fuel as the can be sustained for a long periods of time.

Fuel cells are ideal for power generation, either connected to the electric grid to provide primary power, supplemental power or backup assurance for critical demand, or installed as a grid-independent generator for on-site power in areas that are inaccessible by power lines. They are being used in many different ways in the world today.

· Buses
· Boats
· Trains
· Planes
· Scooters
· Laptop computers
· Cell Phones

These are just a few of the things that can fuel cells can power. There are many more and still more are in development.

Fuel cells are used in many different commercial and industrial applications, and are being seriously scrutinized to become the key component of the nations plan to secure energy for the future.

About the Author:

David Tanguay is dedicated to providing research, reviews & helpful information to consumers and businesses. For more information related to Green Energy and Fuel Cell please visit http://greenenergyonline.org

Article Source: http://www.articlesbase.com/science-articles/fuel-cells-294845.html