Although these technologies are being developed in industrial countries, they will probably do most immediate good in developing countries where they could make communications and refrigeration more widely available to far-flung rural communities. Buy some energy-efficient lightbulbs. If you re living out of halls and pay for your electricity, these will pay for themselves in a year, and you can take them with you when you move. Switch off your TV completely when you re not watching it. Also, if you re working on a PC, switch the monitor off when you re not using it, even if you re not leaving it for long enough to want to shut the machine down completely.
Fridges use lots of power.
They are more efficient if you keep them full, don t put hot things straight into them, and defrost them regularly. Dry your clothes outside on a clothes line. Tumble dryers use an enormous amount of electricity.