Feature: Sensible approaches to green computing

Try making a list of the electronic goodies in your home and you're sure to come up a surprising collection. As you're reading a computer magazine, it's safe to assume at least one desktop or notebook PC. You may have a printer, scanner, digital camera or router.

Home entertainment and communications equipment is an even bigger category with many homes now boasting mobile and cordless phones, satellite boxes, games consoles, audio systems, MP3 players and hard disk recorders.

The there are our washing machines, dishwashers and kitchen gadgets, not to mention the elaborate network of lights and heaters that ring every home. The extent to which we now depend on electricity for essentials tools and life's little helpers is quite astounding.

It's also a worry, according to a growing number of scientists, politicians and charities. Because everything we've mentioned so far has one thing in common: they all devour power, and some of them eat it up all day and night.

Collectively, all these devices have a significant impact on the amount of fuel used to generate the power they consume. The total energy consumption per household is used to calculate what's called a carbon footprint.

This footprint is just a simple way of measuring of how much carbon dioxide you contribute every year to the greenhouse gases that many people fear are over-warming our planet.

With politicians of all persuasions realising that ecological issues are a hot topic, and those who were once sceptical about global warming such as Sir David Attenborough now changing their tune, definitive information and advice is hard to come by.

So we decided to investigate the issue, attempt to dispel myths where we found them and, in conjunction with our colleagues at sister titles Personal Computer World and Computing, develop a set of practical and achievable ways in which technology enthusiasts can make a difference, however small.

We've also put together a website containing many of the news stories and art icles we've written on the subjects of power consumption and sensible recycling, which you'll find at our green computing microsite.

Where the power goes
Power consumption is gauged by measuring in watts: the amount of energy a device consumes per hour. A typical PC with monitor consumes around 120W per hour, while an electric kettle would consumes 1800W if it were used.

Although these figures seem to indicate that computers are not a major factor in driving up household bills and carbon emissions, you have to consider how long each device is used for. Typically, a kettle might be turned on four times a day for a two-minute boil. That's only 8 minutes a day, which means a total daily consumption of 240W.

A PC that's used for home entertainment and internet browsing might be turned on for many hours at 120W per hour – more than of the respondents to our survey said their PC was switched on for 40 hours a week or more, so the PC can make a significant net contribution to global warming.