Simple innovation could keep lights on for Indians, render inverter redundant

Simple innovation could keep lights on for Indians, render inverter redundant

Summary: In power-starved India, this novel solution from IIT Madras could transform people's lives and render the mighty inverter obsolete.

TOPICS: India, Outage

If you've ever lived in India for even a brief period, you're probably familiar with a device that is as much a part of the lives of Indian families as the frothy Hindi television soap opera — namely, the inverter.

In a perennially power-starved India, the inverter and accompanying batteries prevent Indian houses from simmering in darkness during one of the innumerable power shortages the country tends to face, thanks to stalled new power projects and bankrupt state electricity boards. Your average inverter can run a certain number of fans and lights, as well as your television, depending on the number of batteries that have been tacked on.

And now, a bunch of professors from the temple of Indian engineering, the Indian Institute of Technology (IIT), inadvertently plan to render the inverter redundant thanks to a simple innovation.

The brainchild of IIT-Madras director professor Bhaskar Ramamurthi and electrical engineering professor Ashok Jhunjhunwala, also from the Indian Institute of Technology in Chennai, this new technology will deliver 48 volts of direct current to select homes in Tamil Nadu, Andhra Pradesh, Karnataka, and Kerala as part of a pilot project. Once proven successful, it will be rolled out to the rest of the country.

A dedicated 48V low-power direct current (DC) line will snake its way from the substation to houses, and the current will flow through a separate meter to power three lights, two fans, and a mobile charger. Brushless fans and light-emitting diode (LED) lights that can work on direct current will be powered using this DC power.

This means that during regular blackouts, homes can get uninterrupted power from the grid. Instead of completely shutting down the grid, which is what happens when demand exceeds supply, the Discom will merely shift its supply to the 48V line, which will deliver power at a small fraction of the original and at a different voltage.

Considering the regularity of power outages in the country, the growing gap between demand and supply of power and the number of families who have to swelter in the dark because they can't afford a battery-powered inverter, this service could impact millions of people's lives. Other beneficiaries would be the vast education and healthcare landscape that are most affected when the lights go out.

Topics: India, Outage

Rajiv Rao

About Rajiv Rao

Rajiv is a journalist and filmmaker based out of New Delhi who is interested in how new technologies, innovation, and disruptive business forces are shaking things up in India.

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  • Looks like it would double the installation cost--

    Once for the full power line, and again for the low power line.

    With no guarantees that the low power line will get power either.
    • Agree more information is needed, but theoretically someone knows the ...

      source of the problem and if this is a suitable solution. I would wonder if money spent on another line would be better spent increasing primary AC infrastructure (Power Generating capability, quality of the transmission lines/transformers/etc...). One has to hope that someone it thinking through the entire problem/solution cycle before they proceed. Getting rid of the need for batteries might help offset the costs ,but only if there is not a failure that would take out the DC transmission (i.e. transmission line problems, source generation failure that would affect AC as well as DC, ...).
    • Yeah, but it's made to order for a nation

      where incompetent government bureaucrats run everything for the "public good."
  • Do they understand why Westinghouse's AC won out over Edison's DC?

    It was determined early on that a power plant would be needed about every 1 to 1-1/2 miles due to losses of running large amounts of current. Are they seriously suggesting building that many substations?
    • Oh, probably. And someone's brother

      will get the contract.
    • Re:Do they understand why Westinghouse's AC won out over Edison's DC?

      They're still trying to get the country out of the 16th century...and having little success. This took place in the 19th century...far in advance of where India is now.
  • Not a real solution - still grid dependent

    You have to run an entire new separate 48V electric grid out to homes? Yeah, that's going to happen. And then you will be relying on the electric utility and trust them not to shut down this 2nd line. If they were that together they wouldn't be having the shutdown problems in the first place. Also, being 48VDC you need completely different lights and fans etc to run on this, and your tv won't work without a - you guessed it - inverter. And those dedicated 48V devices will not run on regular AC.

    Meanwhile a 500w inverter and say 2 lead acid batteries probably cost less than equipping a home with a new power line, meter, conduit and wiring & appliances. And you can plug anything you want into it.

    Any effort and money spent by a utility on this 'solution' would probably be better spent on trying to eliminate power failures on the mains line in the first place.
  • . . . why?

    With so many ULTRA SMART people (USp), mainly doctors and scientist, that come from India how is this possible? Are these USp so smart they know not to stay in the back-world of India?
    As seen in videos, movies and TV news, India has the largest per capita for bicycles and small motorcycles. How is it possible these folks have not used said vehicles to drive a small cars alternator to recharge the batteries? At least I've never seen it.
    India being soOOOooo poor of a country, where are these peoples brains in respect to there over-population?
    Too many people tapping into the grid = blackouts. DUAH!
  • Simple innovation could keep lights on for Indians, render inverter ...

    the very reason for the existence of very high voltage transmission lines is to mitigate the losses during transmission of power from the source to the end user. with 48 volts the losses during transmission is horrendous that the project will fall on its face... a 12 gauge copper wire (for common household wiring) has a Wire Resistance of 8.385 ohms per mile, meaning for every ampere consumed by one end user will waste 8.385 watts for each mile of transmission distance. so one user using a 48watts appliances(48volts @1ampere) 10 miles away will incur an 83.85watts losses in the transmission wire itself. AND BY THE WAY THE VOLTAGE DROP FOR A 10 MILES TRANSMISSION LINE OF GAUGE #12 IS 83.85 VOLTS, MEANING THE VOLTAGE WILL DISAPPER HALFWAY - IF IT IS EVEN POSSIBLE!!!
  • Simple innovation could keep lights on for Indians, render inverter ...

    sorry for miscalculation, wire resistance has to be doubled since two lines are needed to carry power...
  • Not too fast mister


    "This solution does not involve laying DC lines from substation but an additional low voltage tap at the distribution transformer; instead of load shedding, this low voltage will be supplied along the same wires. A new meter at the customer premises has AC DC outputs. During normal operation, meter powers both AC and DC loads (with internal 48V DC rectifier). With low voltage at the incoming line, meter will shed all AC loads and power only DC. "Essential" loads - lights, fans, chargers total 200W or so will continue to receive power. This will be load limited by the meter. The solution consists of adding low voltage tap switchover at the distribution transformer, and new AC DC splitting smart meter and DC loads and wiring at the customer end. Problems with DC are mostly on the transmission and distribution side which are avoided; customer premises DC is at safe 48 V and high efficiency DC appliances can be used."