Before you choose a computer, monitor or printer, take time out to think about what you really need, and make do with the equipment which meets those requirements. A large computer screen, for example, consumes much more than a standard 12 inch one. And although laser printers are much quicker and give better print quality, they use a lot of power, especially to heat up the drum. So why buy one if you could probably make do with an ink jet printer, which uses less energy and is also cheaper?

The next step is to check out the device�s energy consumption. Although since 1994 an EU directive requires most household appliances to be energy labelled, this does not include computer equipment. The models which consume less usually have an Energy Star sticker which guarantees that they comply with the energy efficiency rules laid down by the Environmental Protection Agency (EPA) of the United States.

The Energy Star sticker is found on equipment which have a function called energy saver installed, which allows them to go automatically into a low consumption standby mode (sleep mode) after a certain period of inactivity, which is normally set at 30 minutes for computers and monitors; and 15 minutes for scanners. For laser printers the time varies from between 15 and 60 minutes, depending on the print speed.

The saving achieved depends on the type of device. A computer with this energy saving certification should be able to reduce its consumption from the 200 watts it uses when it is functioning normally, to a mere 30 watts. The choice of an energy efficient model is especially important in the case of the monitor, since it consumes the same as the computer and printer put together. The most efficient monitors have two successive energy saving modes. After 30 minutes of inactivity they automatically go into sleep mode in which they should consume a maximum of 15 watts. If the monitor is not used for more than 60 minutes, it goes into deep sleep mode in which the consumption is reduced to a maximum of 8 watts. In this way a monitor with the Energy Star label can consume up to 90% less energy than ones without energy management systems.

In the case of the printer, which more than 90% of PCs for home use have in this country, the amount of electricity consumed can be reduced by more than 65%. Depending on the type of printer, the print type (size, paper format, colour or black and white) and the print speed (number of pages per minute minute), consumption can be cut to a great extent.

The Energy Star sticker per se does not ensure that your device is consuming less. You need to make sure that energy saver mode is activated. During sleep mode computers remain operative and will stay connected to the Net. Pressing a key or moving the mouse will wake them up and the computer will return to the state it was in before it went to sleep.

The activation of energy saving systems will not shorten the life of your devices; on the contrary, will prolong it. The sleep mode a scanner goes into after 15 minutes of inactivity is particularly good for it. Currently only 36.2 % of computers for home use in Spain are equipped with this particular peripheral, though its use is growing spectacularly. By using sleep mode you can avoid unnecessary wear on the light source and increase the device�s lifespan.

Sleep mode will increase the lifespan and improve the performance of your printer too. This is to do with the fact that in this mode, devices emit less heat, a factor which is unimportant in the home but in offices it can mean a significant energy and economic saving in air conditioning.

How should you use your computer equipment
It�s no use having the most efficient devices on the market if you don�t use them properly. Or, to put it another way, the fact that your computer equipment doesn�t have the latest energy saving programmes does not mean you cannot save energy.

The different ways of using a PC, in other words what you actually do with it, does not have any significant bearing on energy consumption. The tips we have listed below can be summed up in one sentence: switch things off if you aren�t using them.

� Turn your computer off if you are not going to use it for more than one hour. In that time it consumes the equivalent of 100 grams of coal. Switching it off and on will have no appreciable effect, since the useful life of a computer is usually no more than five years at the most.

� Switch off the monitor for breaks of more than 15 minutes. If you only switch off the monitor, when you switch it on again the screen you were last looking at will come back. But be careful with liquid crystal screens: repeatedly turning them off and on will shorten their useful life. So, if your computer has this type of monitor, make sure it also has an energy saver function too. For conventional monitors switching the screen off and on five or more times a day will only start to cause problems after 20-30 years of use!

� Remember that a screensaver do not turn off the screen. The prolonged projection of the light beam from the cathode ray tubes onto a single spot on the monitor screen will cause damage due to phosphor burn, an effect which is more pronounced when the screen is left on without being used. The screensaver�s job is only to protect the screen from this damage. In fact the monitor will consume almost the same amount of energy with a screensaver as it does normally. Black screen screensavers which leave the screen blank are the only kind which allow you to make some energy saving: 7.5 kWh over animated screensavers.

� Laptops tend to be designed with energy saving in mind, since the life expectancy of their battery depends to a large extent on the number of times it is recharged. For this reason you should plug your laptop into the mains whenever possible. And unplug the power supply whenever the computer is off and not being recharged.

� Use the bookmark systems provided by your computer�s software which will record the screen you were working on when you last switched off, as well as allowing you to access frequently used pages and the most recently used documents and applications. You will save time and energy.

� If the printer is connected to more than one computer -a common situation in the home- it should only be switched on when you want to print something. If you have a laser printer, use the print controller to save documents and print everything in one go at the end of the day. That way the printer only needs to switched on once.

� Connect all you devices to an adapter so you can unplug everything at once at the end of the day. Computers, monitors and printers are all devices which consume energy even when they are switched off. A computer which is switched off but plugged in may consume as much as five watts.

DID YOU KNOW...?
- The first small size, low price computer was launched in 1976. It was called Apple I and was built by Steven Jobs and Steven Wozniak, the founders of Apple Computer, in the garage of Jobs� parental home. Five years later, the multinational IBM launched its IBM Personal Computer, which popularised the term PC. In 1991, IBM presented its first laptop.

- During the year 2000, 1,760,729 personal computers were sold in Spain and more than 100 million worldwide. By the end of that year, 26.9% of Spanish households had at least one computer (Source: Information Technologies in Spain 2000, SEDISI).

- The biggest waste of energy by computer equipment is when they are switched on without being used. Among the findings of the European project Efforts (Energy Efficient Improvement in the Use of Computer Equipment in the European Public Administrations), in which IDAE participated, is that the time a computer is not actively in use in work environments is in the region of three hours per user per day.

- Although since 1999 personal computers have ranked among the products eligible for the European ecolabel, to date no computer on the market has one. For this reason the European Union decided to adopt the American Energy Star label as the official energy saving certification for monitors, computers, operating systems, scanners, photocopiers, printers and fax machines. At the time of writing, the European Commission and the US government are finalising the details for the joint coordination of the labelling scheme.

�