1. Turn off the lights
Remember to hit the switch on your way out for that well-deserved lunch break. The energy savings from 10 million office workers turning off unneeded lights for 30 minutes a day is enough to illuminate four million square meters of office space.

2.Remove yourself from junk mail lists
The last thing you need is another office supply catalogue or credit card offer. But before tossing out junk mail, call the company and ask that your name be removed from its mailing list. Have contacts e-mail you instead. Almost 50 percent of all catalogues are never opened, yet nearly 62 million trees are destroyed and 28 billion gallons of water are used to produce them every year.

3.Send your monitor to sleep
Screensavers are designed to save your screen from burn in, not to save energy. Monitors are responsible for more than one third of a computer's energy consumption, so conserve energy by putting yours to sleep or powering off altogether when you're away from your desk for more than 10 minutes.

4.Use the stairs
Your brain gets exercise all day, so why not exercise your body? Get your heart pumping by taking the stairs instead of the lift. It's good for your health and saves electricity.

5.Make your printer's toner last
If you're printing rough drafts or documents for internal purposes, change the printer's settings to economy mode and avoid printing in color if possible. Economy mode uses up to 50 percent less toner and prints twice as many pages as higher quality settings. Printing on both sides slashes the number of sheets used by 50 percent.

6.Leave the car at home
Public transport may not be perfect, but there are alternatives: why not walk (if you live close enough), hitch a lift with a colleague or try going by bicycle?

7. Recycle paper
If it tears, it can be recycled: from magazines and manila folders to plain paper and post-it notes. Manufacturing recycled paper generates 74 percent less air pollution than creating paper from scratch and saves trees, water and energy.

8.Buy 100 percent recycled paper
When you're buying paper for the office, make sure it's 100 percent recycled and, ideally, non-chlorinated. The chlorine used for bleaching is one of the biggest polluters in the paper-making process.

9. Recycle and reuse office supplies
Washing and reusing the plastic plates and cutlery you get with takeaway food is an easy way to cut down on waste at work. Use mugs rather than disposable plastic cups and don't forget that things such as batteries, printer cartridges, DVDs and CDs can be recycled, too.

10. Curb phantom electricity
Many appliances still use energy even when they're turned off. Items left plugged into the wall, such as a mobile phone charger or laptop adapter, can leak more than 20 watts of power. Plug office equipment into a power strip instead and turn it off at night and on weekends.