It's all in how you look at it, of course. As these life-cycle analyses become further developed over time, I would surmise that almost everything we assume about being "green" or "sustainable" will be negated, reaffirmed, tossed, reconstituted and parroted once again. In other words, a fatalist's wet dream.
Notice how the life cycle analysis of the automobile conveniently goes unmentioned. No use arguing, though, as these are foregone conclusions, I suppose.
$this->bbcode_second_pass_quote('', 'W')alking to the shops ‘damages planet more than going by car’
Dominic Kennedy
Walking does more than driving to cause global warming, a leading environmentalist has calculated.
Food production is now so energy-intensive that more carbon is emitted providing a person with enough calories to walk to the shops than a car would emit over the same distance. The climate could benefit if people avoided exercise, ate less and became couch potatoes. Provided, of course, they remembered to switch off the TV rather than leaving it on standby.
The sums were done by Chris Goodall, campaigning author of How to Live a Low-Carbon Life, based on the greenhouse gases created by intensive beef production. “Driving a typical UK car for 3 miles [4.8km] adds about 0.9 kg [2lb] of CO2 to the atmosphere,” he said, a calculation based on the Government’s official fuel emission figures. “If you walked instead, it would use about 180 calories. You’d need about 100g of beef to replace those calories, resulting in 3.6kg of emissions, or four times as much as driving.
“The troubling fact is that taking a lot of exercise and then eating a bit more food is not good for the global atmosphere. Eating less and driving to save energy would be better.”
...
Also,
Shattering the great green myths
— Traditional nappies are as bad as disposables, a study by the Environment Agency found. While throwaway nappies make up 0.1 per cent of landfill waste, the cloth variety are a waste of energy, clean water and detergent
— Paper bags cause more global warming than plastic. They need much more space to store so require extra energy to transport them from manufacturers to shops
— Diesel trains in rural Britain are more polluting than 4x4 vehicles. Douglas Alexander, when Transport Secretary, said: “If ten or fewer people travel in a Sprinter [train], it would be less environmentally damaging to give them each a Land Rover Freelander and tell them to drive”
— Burning wood for fuel is better for the environment than recycling it, the Department for Environment, Food and Rural Affairs discovered
— Organic dairy cows are worse for the climate. They produce less milk so their methane emissions per litre are higher
— Someone who installs a “green” lightbulb undoes a year’s worth of energy-saving by buying two bags of imported veg, as so much carbon is wasted flying the food to Britain
— Trees, regarded as shields against global warming because they absorb carbon, were found by German scientists to be major producers of methane, a much more harmful greenhouse gas
...
Times Online