WHY ALL THIS FUSS ABOUT ELECTRIC CARS?

Did you know that 25 percent of fossil fuel ever consumed by human beings was in the last 10 years? Thanks to the 800 million cars on road today. This number is expected to rise to 2 billion in 2050. Today, a quarter of all carbon emission comes from cars and trucks. Imagine what would happen, if the number of vehicles reaches 2 billion in the future. The answer to this problem is quite obvious – reduce carbon footprint per vehicle. One of the significant solutions to reduce carbon footprint is by using renewable resources instead of petroleum to fuel vehicles.

Switching to renewable resources can be done in more than one way. Iceland has already adopted one of them – use of hydrogen fuel cells. Public transportation in Reykjavik consists of only hydrogen powered buses. Hydrogen fuel cells include a catalyst, which is instrumental in breaking up of hydrogen atoms into hydrogen ions, thereby creating free electrons. These free electrons are responsible for the flow of electricity. Hydrogen ions thus formed combine with oxygen in air to form water as a waste product. The obvious advantage is, the whole process is clean as the only waste product is water. However, they have a couple of disadvantages. Hydrogen is not freely available in nature; hence some amount of energy is spent in dissociating hydrogen from its compounds (energy needs to be spent to produce energy!!!). Moreover, since this process necessitates storage of hydrogen, it is risky considering that hydrogen is extremely inflammable. Using hydrogen fuel cells in vehicles would demand installation of hydrogen refueling stations, which underlines the risk of storing hydrogen. The above problems revoke the exploitation of hydrogen as an alternative to petroleum. Hence the need for considering other options as an alternative to petroleum.

Ethanol made from corn, looks like a good solution to some extent. However, production of ethanol from its raw products (mainly corn) also consumes a lot of energy. Some critics claim that they consume more energy than they produce during combustion (process of burning the fuel to generate energy). Scientists are also working on making lighter (but stronger) cars made out of materials like carbon composites. At the same time, research is being carried out to make more aerodynamic auto bodies. Lighter and more aerodynamic auto bodies would reduce the consumption of fuel by a large extent. This has already been proven by Boeing with the launch of their new dreamliner (787), which makes use of a carbon composite body to reduce fuel consumption by 20 percent. However, the manufacturing process of the auto body from this material is much more expensive than manufacturing it from steel/aluminum. Hence, vehicles made out of lighter materials do not seem to be a viable solution until there is a revolution in their manufacturing technology.

Issues like the ones mentioned above are responsible for the “need for electric cars”. Batteries used for storing electric charge make up the heart of any electric car. The foremost problem faced by the electric car industry today is twofold - batteries are not good enough to store electric charge to fuel the car for more than 200 miles and it takes a long time to charge them (around four hours to charge a Tesla Roadster). Hunt for the right battery technology is the key to success. Hence, revolution in the electric car industry lies in the hands of battery manufacturing companies. Recently, a battery manufacturing company called EEStor has announced that they are testing a technology that could charge batteries within thirty minutes. Chevrolet has also claimed that they are working on batteries that can be charged not just by power supply, but also by gasoline, ethanol and hydrogen fuel cells. This extra charging cabaility will give them an ability to sell cars (Chevy Volt) that have no range limit!! Most probably, with the invention of batteries that can charge sooner, gas station will gradually begin to be replaced by electric charging stations. How true could this be? Well, a survey of U.S. licensed drivers showed that 10 % of the drivers would consider purchasing a hybrid or an electric car. Where there are customers, there is a market. This could clearly be birth of electrically driven vehicles.

ABCs of LEDs and LECs.

Time has come to say goodbye to good old "Edison bulbs". It was around 1900, when the Director of US Patent Office declared openly that "whatever that can be invented has already been invented". He certainly did not know what was going to come. Lets take the example of LEDs. For a given amount of light output, LEDs consume only one-fifth to one-sixth of the power consumed by incandescent bulbs. Though it sounds incredibly hi-tech, simple physics is all it takes to make an LED work. Not really true, a little bit of quantum physics is actually involved in it. Well, for starters, when an electron combines with an absence of electron (called hole), light is generated. If its so simple, why did it take so long to start using LEDs as a light source?

The answer is "it did not". The first LED was manufactured in 1962 by GE. In the late 60s and early 70s, they were being used in electronic equipments, but had very little application in everyday usage. This was due to their high manufacturing cost. However, over a period of forty years, due to advancements in material science, this cost has reduced, and now, they have plenty of applications. People would still consider LEDs as an expensive option, but I would like to throw some light on "how LEDs can be cheaper than incandescent bulbs".

Facts about incandescent bulbs : Lifetime of a 100 watt incandescent bulb is about 750 to 1000 hours. A 100 watt bulb gives a light output of 1700 lumens (a measure of how bright the light is). A typical 100 watt bulb costs around $ 1.

Facts about LEDs : Lifetime of an LED is 50000 hours. A good LED nowadays, gives a light output of 100 lumens. Hence, to get 1700 lumens, 17 LED are required. Each LED costs around 5 dollars approximately. Hence 17 LEDs would cost $ 85. However, there are some additional costs involved in using LEDs. This is because, LEDs are current driven devices, due to which, if the current passing through them varies from the specified current, its light output would vary too. Hence the requirement for LED drivers, which allow these devices to operate at a constant current. Moreover, because of the physics involved in the working of LEDs, there is a lot of heat generated along with the output light. This necessitates the use of a Heat Sink to get rid of the generated heat (the excess heat generated might fry the LEDs if not sinked).

Including all the accessory costs, using LEDs to get 1700 lumens for 50000 hours would cost around $ 100 ($ 85 for LEDs + $ 10 for an LED driver + $ 5 for a Heat Sink) without considering energy costs. Similary, using incandescent bulbs for 50000 hours would cost around $ 50, as one would need 50 bulbs to go on for 50000 hours, considering the lifetime of a bulb to be 1000 hours. Now, if you are thinking that bulbs are cheaper than LEDs, keep on reading, because, if you remember, I have already mentioned that LEDs consume only one-fifth of the power consumed by bulbs.

Elaborating more on energy costs, one would need 100 watts of power to obtain 1700 lumens from a 100 watt incandescent bulb. To go on for 50000 hours, a total of 5000 KWh of energy would be spent. Similarly one would need only 1000 KWh of energy to run LEDs at 20 watts for 50000 hours. Cost of electricity is currently around $ 0.12 per KWh, which makes the total energy cost to run bulbs to be $ 600 as compared to $ 120 only, that is required to run LEDs. You may now appreciate the fact that "LEDs are much cheaper than incandescent bulbs - a true win-win situation".

If, you have already changed your mind to switch to the "greener-cheaper" LEDs, you would need three devices to get the final light output, LEDs, LED driver and Heat Sink. Few of the best companies out there manufacturing LEDs are Cree, Nichia, Osram etc. For LED drivers, there is National Semiconductor, Analog Devices etc and for Heat Sinks, there is Aavid, Advanced Thermal and so on.

Not to mention the biggest advantage of the LEDs, they have the best color rendering index of any light source available in the industry. In common man's words, anything you see under a yellow incandescent bulb would have a yellowish shade to it. For example, a white colored paper would look yellow in a yellow colored light. This problem is totally avoided with white LEDs. If LEDs are so good, why all this fuss about LECs? Light Emitting Capacitors or LECs are simple parallel plate capacitors with a phosphor coating on the dielectric. When current is passed through the capacitor, this phosphor layer glows, causing it to behave like a light source.

As for any light source, LECs have their own pros and cons. Though they consume just one third of the power an LED would consume for a given light output, LECs have an extremely niche market at this point of time because they are far more expensive than their LED counterparts. However, I can see the LEC market to be at the exact same position as the LED market was, about 30 years ago. As history repeats itself, 30 years from now, I would expect LECs to rule the lighting industry.

Industrial Revolution of the 21st Century - Green Technology

With the new Obama administration focusing on going green, companies are realizing an opportunity to make a difference by foraying into "alternative energy technologies". Obama's new energy plan (as of June 2009) includes an investment of $ 150 billion over the next ten years in renewable resources. This is one of the most important steps to be taken to ensure that at least 10 % of our electricity comes from renewable resources by 2012 and at least 25 % by 2025. Well, the bad news is, in 2009, this number was just under 2 % (including Geothermal, Photovoltaics and Wind) - Monthly Energy Review magazine.

How can we account for such a huge difference in just 2 years? The answer lies in "competition". Solar (PV) and Wind energy sources have seen the most development in the past one year. This can be reflected in an increase in the number of start-ups manufacturing solar cells. Companies like Solyndra, Nanosolar and BrightSource are among the torchbearers. The reason I mentioned about these three companies is that, each one of them is different and more innovative than the other. While Solyndra and Nanosolar specialize in "thin film PV cells", Brightsource excels in "concentrating PV". Solyndra owes its success to the cylindrical shape of its PV cells, which helps in utilizing more of the incident sunlight to be converted into electricity, increasing the conversion efficiency. Nanosolar owes its success to the patented solar cell manufacturing process it has developed, which basically involves printing ink containing nanostructured solar cells on a substrate like "sheet of paper", allowing it to deliver one of the "world's least expensive PV cells". Brightsource has laid its feet on Solar-Thermal technology, which uses mirrors to reflect and concentrate sunlight onto a boiler containing water, consequently producing superheated steam (550 degrees C) which is used to run turbines, thereby generating electricity. Talking about their success, Solyndra has recently filed for an IPO of $ 300 million and BrightSource has bagged a 1300 Megawatt project from PG&E, sufficient enough to power 530,000 homes.

We just talked about clean generation of electricity, but what about efficient usage of energy? Well, this is an era of LEDs and electric cars. LEDs are approximately 300 percent more efficient than incandescent bulbs and 15 percent more efficient than CFL. With recent innovation in LED technology by companies like Cree and Nichia, they are more than 500 percent more efficient than incandescent bulbs. That's like getting the same amount of light output by dissipating just one-fifth of the power used by an incandescent bulb. As far as fuel efficient cars are concerned, with introduction of Prius, we went from burning 20 mpg of gas to 50 mpg. With Tesla roadster, this number has risen to 135 mpg (equivalent to offering 250 mile range per 4-hour charge) and with their new "Model S", the new value is around 200 mpg (equivalent to offering 300 mile range per 1-hour charge). To keep up with the competition, car makers like GM and Fisker automotive are coming up with cheaper, more efficient solutions. Looks like we are finally going to save this planet from GLOBAL WARMING!!!