energy

Robin Roy, Professor of Design and Environment, Design Innovation Group, Faculty of Maths, Computing and Technology, on tackling climate change at home...

Homes are responsible for more than a quarter (27 per cent) of greenhouse gas emissions produced by the UK; mainly carbon dioxide released when burning gas for household heating and hot water and generating electricity for lights and appliances. Here are some of the most important things you can do to reduce your own and your household’s climate changing impacts:

Home heating and hot water

Apart from transport, this represents the largest share of most people’s energy emissions. To reduce the amount of fuel you use for heating, insulate your loft (with 1ft-thick insulation) and walls (cavity filling is easiest, but solid walls can be insulated too). Try to take showers rather than baths to save hot water. Consider upgrading your heating and hot water system, preferably to central heating with a condensing gas boiler that is maybe supplemented by a wood stove. Only then install double glazing and/or insulate floors if your home hasn’t already got these improvements. Finally you might consider installing a solar water heating system, especially as by 2012 there will be a ‘renewable heat incentive’ to pay you for any solar hot water you produce.

Electricity for lights and appliances

On average this represents 12 per cent of household emissions. Reduce your electricity consumption by getting energy-efficient appliances (especially fridges and freezers which consume most electricity) and turn off lights and electronic equipment when not in use. Replace ordinary light bulbs with energy-saving ones – there are now lots of types including efficient lamps to replace halogen spotlights and new LED lamps bright enough for proper lighting.

It’s now becoming worthwhile to consider installing a solar photovoltaic system for generating electricity, as there is a generous ‘feed-in tariff’ to pay you for any electricity you generate at home. A solar electric system (best installed before April 2012 when the tariff may be reduced) can now pay back in about 10 years and earn the equivalent of an eight per cent return on your money. However, a much cheaper and easier option is to switch your electricity supply to a ‘green’ tariff; preferably one that relies on 100 per cent renewable sources such as wind power.


Take it further
Discover your own main sources of greenhouse emissions by using a carbon calculator, developed for module Environment: journeys through a changing world (U116), on OpenLearn.

Watch the video tour of the home of Dr Richard Blundel, a Senior Lecturer in Enterprise Development with The Open University Business School, who has spent years transforming his Edwardian home into an energy efficient one.

For more resources related to the environment and climate change, go to www.openuniversity.co.uk/climateweek
 

MCT Lecturer in Technology Management Malcolm Fowles provides advice on how to save energy in your work and home offices...

Portable versus desk computer
Using data shared by my students on T152 Energy measurements at home, we found that our laptops used on average about a third of the power of our desktop computers. If these are typical, and work an eight hour day, the difference between them is about £25 per machine per year at domestic electricity prices. Another difference, of course, is at least a third of the damage to the environment.
If you have the choice, use portable.

Screen savers
Your screen doesn’t need saving! Very few of us now use an old-style monitor that engraves a static image on the tube, but many of us still run a screen saver. Far from saving anything, most screen savers actually use more energy than ordinary office software. Our worst offenders tended to be those that render 3D objects, and those that cycle round photographs.

Attached devices
Any device connected to your computer may be using energy, even if you think it is switched off. Trust nothing. For example, my USB memory stick adds a constant 20 per cent to my laptop’s energy usage when plugged in. A laser printer on standby may be drawing as much power as a low-energy notebook computer. Even a power cable with no machine attached may be using energy if it is in a socket that is switched on!

Powering down
A typical computer left idle uses very nearly (more than 98 per cent) as much power as one being used continuously for normal office tasks due to the way the processor works.
Why do we leave our computers on? It appears that the main reason is the time it takes to restart after switching off. The longest reported delay, from start-up switch to password prompt, was five minutes. The average was 97 seconds – more than a minute and a half. That kind of delay is not acceptable to most people during the working day or when at home.

There are, however, alternatives to powering down your machine if the start-up time is an issue. Almost all computers have power-saving options, primarily these are that the processor stays on but the screen (monitor) is powered down; the processor is powered down after all contents are saved to memory for a quick restart, often called Standby or sometimes sleep mode; the processor is powered down after all contents are saved to disk for a fairly quick restart, often called hibernate or sometimes (confusingly) sleep mode. All of these alternatives have much quicker restart times than a shutdown.

Taking it further

• The Carbon Trust has developed a fact sheet with tips and guidance on saving energy in the office
• To find out more about all things environmental, go to the OU’s OpenLearn website which has brought together educational resources on the topic