06 August 2015 14:37:07 IST

It’s time to be direct and current

Concerns about climate change and energy efficiency could see the wider adoption of direct current

Once upon a time, a long time ago, there lived a man called William Kemmler. His father was an alcoholic and his mother was… well, no lady. So, little William had a poor upbringing — in fact, he had no upbringing at all. He turned out to be a petty criminal and, what with one thing or the other on his mind, he ended up killing his wife.

William Kemmler lived in America at a time when electricity was just coming into people’s regular lives. Two major companies fought for supremacy.

You would know them by their current names —GE and Westinghouse. The competition was not just for market, but also for technology.

GE wanted America to run on direct current, or DC, while Westinghouse wanted alternating current, AC. (As you know, AC is what is widely used in the world today, including in our houses.) You can read a lot on this ‘war of currents’.

GE had its origins with a man you all know quite well — the man who invented the filament bulb, the wizard of Menlo Park, Thomas Alva Edison.

Dark side to Edison

Now, something connects the crook William Kemmler and Thomas Alva Edison. You all know Edison as a great inventor, a genius, blah, blah, but flip him around, and you see him in very different light. Edison, in order to show AC as ‘dangerous’, killed a lot of animals using that type of current — cows, horses, etc. — to scare people away from AC and towards his preferred DC.

Then William Kemmler killed his wife. Unlike today, when we give out capital punishment only in ‘rarest of rare cases’, death penalty was pretty common, especially in the ‘civilised’ West. So, poor Bill was sentenced to the gallows.

At that time, somebody came up with the idea of ‘electric chair’ – tie the convict to a chair and pass 1,000 volts of electricity through him. Thomas Alva Edison liked the idea very much. He lobbied heavily in favour of the ‘electric chair’.

On August 6, 1890, exactly 125 years ago to date, William Kemmler became the first man to die in an electric chair. Thomas Edison did show that AC could kill. Bill Kemmler lost his life, but Edison lost the battle. AC won, DC lost.

Energy savings

Now, why are we talking about all this in this CleanTech column? There’s a good reason.

Today, energy saving is a key part of ‘cleantech’ and DC is integral to energy efficiency. Come to think of it, today we are seeing a solar revolution. Over time, millions of roofs will have solar panels and, in fact, it would be deemed downright silly to build a roof without a solar panel. The Government has plans to build a monstrous 40,000 MW on roofs, (in which, by the way, educational institutions will play a key role.)

Solar panels produce DC. Today, we convert the DC into AC — lose a lot of energy right there — and use the alternating current to run our fans and refrigerators, consuming more electricity. Instead, if you can wire the panel to the appliance, you can save a huge amount of power (and money). The problem is, the appliances we use are designed to operate on AC.

Storage devices such as fuel cells produce DC. Even in storage we lose energy. Convert the DC into AC, and you lose more.

Now, come to the other end — consumption. LED lights need DC, not AC. It is pertinent to mention here that there is today a worldwide movement to get all the lighting points to use only LED.

Conversion to LEDs

If you want to know a little bit more, there was a ‘Cleantech Ministerial’ meeting in Mexico this June, when 23 countries decided that they would convert 10 billion, (repeat, 10 billion) lights to LED — of which 1 billion will be in India. LED lights need DC.

Other energy-efficient appliances are entering the market. Many of them, which have motors in them, are coming with what is called ‘brush-less direct current’, or BLDC. These BLDC motors, being based on DC, are extremely energy-efficient. They consume just a fourth of the power an AC induction motor would consume.

Thus, you have sources of energy producing DC, and you have an increasing number of energy-consuming devices that need DC, yet the system we operate with is AC.

Return of DC

Going forward, what with the concerns about climate change, there will be an increasing stress on energy efficiency and DC will come back. There is a call for it. In fact, there is an entity called ‘Low Voltage Direct Current’, or LVDC Forum, which seeks to encourage manufacturers to come up with DC-based devices. The Forum, based in Bengaluru, is unfortunately not very active, but hopefully it will be in the future.

The movement towards DC will be partly driven by a programme of the Bureau of Energy Efficiency, part of the Ministry of Power. The BEE has brought in what is known as the ‘PAT regime’, the abbreviation standing for ‘perform, achieve, trade’. Under this regime, 478 energy-intensive companies (in sectors such as cement, steel and power) were given energy-efficiency targets and three years to achieve them.

The three-year period ended on March 31, 2015. Right now, they are verifying the achievements. Those who over-achieved would be given what are known as ‘energy savings certificates’ or Escerts, which can be sold in the market to those who could not meet the targets. Thus, a market-based mechanism has been evolved for funding energy efficiency projects. The PAT regime is in its infancy. Over time, more companies will be brought under its ambit and there will be a lively market for Escerts.

In such a scenario, companies will demand DC products. DC will make a comeback. At least, on this 125th death anniversary of William Kemmler, we should hope for it — after all, he was made to die for DC.