1. Zero Carbon the Holy Grail

A genuinely sustainable economy must be carbon neutral - "Zero Carbon" doesn't mean we can't emit any carbon at all – but it does mean we have to stop adding to the total amount of free carbon in the system. Building a low carbon economy and phasing out fossil fuels is a hugely complex challenge - there's no map for a low carbon economy - so how do we find our way through the maze? All the pages in this section have a handy "carbon counters dictionary" on the left to help you understand the jargon!

 Thinking about Carbon

 Even the greatest cartographer would struggle to define the route through the millions of decisions about thousands of variables that shape our world. They are the social equivalent of the cellular level changes that shape the development of an embryo. Just as DNA code influences the cellular “decisions” that build and shape all life forms, so the day to day choices we make shape and mould our society.

Our “code” is the questions we run when we make decisions. “Is it trendy”, “will my wife like it”, “does it make my bum look big”, “car or bus”, “beef or lentils” - there's a long list that changes according to subject but its almost always subservient to “can I afford it?”. We run this routine whenever we make a choice, subconsciously for the little things and, if we have any sense, carefully and consciously for the big things. Knowing the code means we don't need a map or a list of detailed instructions about what we should or shouldn't buy. We need a similar code to help us to make decisions that will reduce our carbon intensity. The question “does it make my carbon footprint look smaller?” has to be embedded into our decision making code - to be able to answer it we all have to become carbon literate.

Put the question “does it cut my carbon emissions”, at the centre of our decision making, and, providing the default answer is "yes", a low carbon world will evolve with no other organising principle. This may sound a bit over the top – but don't underestimate how much of a difference our individual behaviour can make.

A recent Cambridge University analysis of energy use reckons global energy demand could be cut by 75% using mainly existing technologies. Some of its projections, like the “300 kilo car” may sound like a sci-fi story, but Volkswagen's prototype XL1 hybrid car, weighing in at 770 kilos, (313 mpg combined cycle and accelerates from 0-60 in 11 seconds) is due to start production in 2013. Others are far more workaday and are well publicised – reducing thermostat temperatures on washing machines and dishwashers, good draught-proofing, good insulation – most are changes that we need to make over time, as and when the moment comes to change a boiler or a major house refurbishment - but knowing the "code", being carbon literate, will help our individual decisions contribute to a less carbon intense economy.

Carbon and energy costs

Understanding the vocabulary, terms like carbon intensity, embedded carbon and carbon footprint, give us a set of tools to help analyse how the things we do, buy and use contribute to greenhouse gas emissions. There's often a reasonably direct relationship between carbon and energy costs but the link isn't always clear cut.

There is a 10 fold difference in the carbon cost of a kW of electricity from wind, nuclear and the most inefficient thermal generators. The benchmark for fossil fuels is 400g CO2/kWh, the total carbon intensity of nuclear power, including construction, waste storage and decommissioning is 40g CO2/kWh (similar to wind). Steel produced in China has twice the carbon cost of steel produced in the UK - transport contributes a little to this difference but for the most part it's due to the carbon intensity of energy production in China compared to the UK. In both cases there isn't of necessity a straightforward link between the energy produced or consumed and the carbon intensity of the product but very often carbon intensity is a good guide to the energy cost of things we do and things we use.