A generation ago, the phrase ‘carbon footprint’ would have meant little to most of us. But now our lifestyle and consumption choices – from what and how we eat to the modes of transport we use – are increasingly shaped by ecological considerations.
The problem, though, is that a number of commonly-held beliefs about our environmental impact stem from half-truths, hearsay and myths. Did you know, for example, that it takes more energy to produce a paper bag than its plastic equivalent, or that reusable nappies are not necessarily greener than the much maligned disposable ones?
Just as surprising, perhaps, a 2012 survey of 1,000 Hungarian consumers found that people who try to make their diets, energy use and travel habits environmentally friendly actually have just as large an impact on the environment as consumers that don’t change their behaviour.
Here are five of the most common misconceptions about our environmental footprint:
1. If we stop using fossil fuels, we’ll end global warming
Fossil fuels account for around 80-90 per cent of our CO2 emissions. But, while CO2 is the main greenhouse gas responsible for climate change, there are many others and fossil fuel use is far from the only problem. “Agriculture, forestry and changes in land use make up about 25 per cent of total greenhouse gas emissions,” says Rachel Warren of the Tyndall Centre for Climate Change Research. “The carbon component comes from deforestation and degradation of forests, but people don’t necessarily realise that deforestation contributes to climate change – and even some of the students I teach don’t know the impact of land-use change.” The United Nations’ Reducing Emissions from Deforestation and Forest Degradation (REDD) programme is addressing this problem all over the world. In Brazil, for example, REDD and other initiatives have slowed deforestation by 75 per cent since the early 2000s, but much more still needs to be done.
2. Recycling is the best thing you can do to reduce your carbon footprint
According to a 2009 European Commission survey, consumers consider recycling as the single most important thing they can do to protect the environment. But the facts reveal that for an average person, heating or cooling their home is the most significant component of their carbon footprint. Households are responsible for about 18 per cent of global energy consumption. Reducing electricity use, insulating your home, choosing the best way to get from A to B (air, road, rail, bike or by foot) and generally being less of a “consumer” of food, gadgets, clothes or paper will reduce your carbon footprint more than recycling what you consume.
3. Leaving your TV on standby wastes vast amounts of energy
While it’s clearly wasteful to leave devices on all the time, modern TVs and laptops consume little energy in “standby” or “hibernate” mode: one month on standby is the equivalent of boiling just one kettle of water. However, new devices have created new problems. “Routers, set-top boxes and the like are in network standby mode most of the time, with some background communication going on. A smart, networked home will have many more of these new standby power consumers, which are a significant power drain, the like of which we did not have in the past,” says Karsten Schishcke of the Department of Environmental and Reliability Engineering at the Fraunhofer Institute in Berlin.
4. Buying local food is better than buying imported products
It depends on the season. In some cases imported food has a lower carbon impact than the domestically produced variety. Most vegetables, fruits and flowers grown in northern Europe are produced in heated greenhouses and therefore rely on fossil fuels. Importing tomatoes from Spain, where growing such food does not require additional heat, can be up to 10 times more energy efficient than producing them in greenhouses in colder countries. But the environmental impact of imported fruit and vegetables pales in comparison with that of meat. “Ruminant animals, such as cows and sheep, have an extraordinary impact on global emissions,” says author and clean energy expert Chris Goodall. Methane – the second most prevalent greenhouse gas – actually has a more potent greenhouse effect than carbon dioxide, and 35 per cent of the methane in the atmosphere is produced by ruminant herds. “It’s not just the methane from digestion though but the carbon cost of fertiliser to grow the grain that the animals are fed and the large amounts of land they require.” So one fact remains true – a vegan diet is a greener diet.
5. Taking the train or driving has less environmental impact than flying
If you lead a jet-setting lifestyle, this could be true. “Flying can dwarf all other parts of an individual’s carbon footprint, as a couple of long-distance journeys might double a person’s total emissions for a year,” says Goodall. Even so, although air travel has by far the worst impact per distance travelled on paper, in some circumstances flying can be better for the environment than both driving and taking the train. For rail travel it depends on the country you’re in, again because of how the energy is generated, but also because empty carriages can skew the per-passenger figures. Similarly, the ecological impact of road travel depends on passenger numbers, as well as on the type of vehicle you drive, how you drive and how often.
What if you drive an electric car? Astonishingly, the raw materials and energy needed to build the lithium-ion batteries in electric cars meant that some can have almost double the global warming impact of conventional cars. So if you drive your petrol or diesel car efficiently in a country that relies on coal-fired power stations, the carbon impact of changing to an electric vehicle might well be higher than that of sticking with your older car, at least for now. “Within five years, electric cars are likely to be cheaper. When we get to this point, the petrol or diesel car is dead.”
The full picture
“Reducing the environmental impact of technology is both a business-model challenge and a technical one,” says Schischke at Fraunhofer IZM. Technology companies are beginning to recognise this, with well-known brands like Apple disclosing their environmental credentials and taking steps to reduce their impact across product life cycles and the corporate value chain.
The sustainable alternative to the “take, make and dispose” approach to manufacturing is gaining traction worldwide. It now has its own label, the Circular Economy. One advocate is Dutch social enterprise Fairphone, which has applied ethical values to every element of its smartphone, from materials and design to manufacture, repair and recycling. Puzzlephone – the invention of a small Finnish start-up Circular Devices – works on the same ethical principles, with a modular design that can be repaired and upgraded easily by the user, and even taken apart and re-purposed at the end of its life to form part of a PuzzleCluster computer. “It’s really great to see what can be done if you approach product design from a circular economy perspective,” says Schischke.
