Advertisment

Here Comes the Sun

author-image
PCQ Bureau
New Update

The sun gives light and life, and makes life hell in the Indian summers. Air-conditioners struggle against the sun, trying to cool a few million people, guzzling power from dirty coal that's pumping greenhouse gases into the atmosphere.

Advertisment

It's a vicious circle: those power-guzzlers suck up the limited electricity supply, tripping grids and requiring widespread 'load shedding' in summer, making life miserable for even those who cannot afford air-conditioning.

How ironical that the sun indirectly causes our energy crisis in summer. For it's the sun that can solve it.

Advertisment

The sun is our most plentiful energy source. Our small planet gets 174 billion megawatts of solar radiation, about half of which reaches its surface. In one minute, the earth's surface gets more energy than will be used by the world in two days.

It is stupid, then, to not use this resource.

Where do you begin, though? Hunting for solar energy options for my upcoming green house (the first project be registered under TERI's SVAGRIHA green-building program), I found the options complex and expensive. There is of course the solar water-heater, which is simple enough and a must-do today (my future house will not have electrical geysers for heating water). The problems come up when you go to solar PV (photovoltaic) cells to generate electricity.

Advertisment

Solar power is far from competitive yet. A quick check suggests I will need to spend over Rs 6 lakh for the 2 kWh that I have to generate, for the green-building rating. That's over twice the cost of such an installation in the US. Much of the cost of solar energy is in the storage-in India. Where do you store all that power, for the nights and cloudy days? In enormous banks of batteries, which need replacement every few years (while the PV panels last over 20 years).

Why 'in India'? Because you don't have such a heavy storage cost in many countries. You can cut down or even do away with storage altogether, using the electrical grid as your 'battery'. Generate power in the sunlight hours, when power tariffs are high. Use the power you need, and push the rest into the grid through a two-way meter that records what you're 'selling' to the grid. At night, you buy it back from the grid. You are billed monthly, only for net electrical usage.

Such two-way 'net metering', not available in India, has obvious advantages. With the money you save on battery storage, you can buy more solar panels, generating more power than you need. Your monthly electricity bill could be zero, or even show a credit balance. Cutting back the subsidy on diesel is a positive step for India, despite its unpopularity.

The subsidy should move to cleaner sources of energy, with a strong focus on solar in this sun-drenched country. With the right moves, we can secure our energy future, winding down dirty coal, petroleum and dangerously dirty nuclear power.

Advertisment