INBOX:HAD I been writing this week's column a few years ago (come to think of it, I was!), I would have been extolling the benefits of monitoring your electricity consumption almost purely as a salve to your conscience.

We have all been told to be more green; on that there can be little argument.

But these days there is added urgency to the idea. Straitened times mean that any gadget which helps us save money is a good thing. If it helps the environment at the same time, then all the better.

So I’ve been trying out the Wattson Energy Monitor, a stylish-looking slab of plastic that pulsates with information about your home’s voracious consumption of watts.

It’s a clever little beast. It will store up to 28 days of your electricity usage data on its – fairly tiny – 32kb memory. Once stored, you can then download the information by connecting it to your PC through a USB connection. Thus in a short time you can start to put your energy consumption on a graph.

Oh brave new world. Graphs are a fantastic way to show the other people in your house – teenagers, wives, husbands – exactly why it’s a good idea to turn off the TV rather than leave it on standby, and, why yes, showing what happens when your teenage daughter uses her hairdryer less might mean she’s allowed to hit Bebo.com on the PC a bit more.

And speaking of social networks, there’s even one attached to the Wattson.

You can publish and compare your home’s stats online with other Wattson users, and trade tips on how to save energy, if that is your wont.

Installation is pretty simple. You attach its sensor clip to one of the mains cables leading to your fuse box, then switch on the Wattson, which displays the data in watts or more importantly in cash terms on its LED display. The main unit is wireless and just needs to be plugged into the wall at a point where you will see it most often. I tried mine out in the kitchen.

This is not its only trick. The unit has lighting underneath which glows a warm purple or blue depending on whether you are using more or less electricity. Try moving around the house and switching things off; after a while it’s a game to get the Wattson to wink its message of approval.

Gradually, I became Wattson obsessed. Like the Hal 9000 computer in Stanley Kubrick’s 2001: A Space Odyssey, it would give a disapproving glow every time I switched on the kettle for a coffee. “I’m sorry Mike, I’m afraid you can’t do that,” it seemed to say . . .

After a while I had to turn my back on the Wattson if I was to have a conversation with my wife.

Could it be measuring my CO2 output as I talked? Is all this information going to be sent back to Wattson HQ for processing? Would I be awakened one night by the sound of Wattson stormtroopers breaking down my door, poised to smash the red lights on my electric alarm clock with a hammer?

In a word, no. My electricity bill is plummeting because I’ve been made aware of just how much electricity I was using before. Now the Wattson and I are more than firm friends.

I just have to tell the wife . . .