Q Would boycotting Chinese goods help send a message about cutting their CO2 emissions?

A I can see where you are coming from. The motivation to install energy-saving light bulbs in your own home is that much less when you hear that China is building coal-fired power stations at the rate of two every week and has surpassed the US as the leading emitter of carbon on the planet.

Punish the polluters, it is tempting to cry. But, before you do, remember that China has more than four times the population of the US and most citizens do not own cars. What inflates its carbon footprint is industry and the rate at which it is building – China produces 44 per cent of the world’s cement, a process that is a major source of greenhouse gases.

“A boycott would wrongly treat climate change as a blame game,” says a Foreign Office spokesman. “Climate change should instead be viewed as a shared dilemma.”

However, if you ask me, a boycott would not be entirely pointless. An attempt to avoid buying anything from China for a few weeks would doubtless be an eye-opener. It would demonstrate the extent to which our economy is reliant on China’s booming manufacturing industry. From computers to clothes, almost everything in our shops has been shipped over. Even our recycling is reprocessed there.

In the UK, there are few facilities to cope with the amount of mineral water bottles we generate, so plastic ends up being sent overseas. If we were to stop buying back the goods made from our waste, I suspect it would end up in landfill.

That the Chinese are more concerned with building a prosperous future for their country than curbing climate change is understandable. We have had free rein to industrialise for 200 years and we have wealth to show for it.

Rather than blocking China out, we should demonstrate how the country can retain its growing economy while still cutting emissions. How? By doing this ourselves.

Q To save energy, should I run my dishwasher and washing machine on economy or on quick wash?

A For this query, I turned to Miele, one of the more eco-aware appliance makers. (In 2004, Ethical Consumer magazine ranked it best in durability and water efficiency.)

A Miele spokesman told me that running a slow two-hour dishwasher cycle is better than rushing through a half-hour one. “The economy cycle starts with a cold-water wash and then reuses the same water, slowly heating it up,” she said. “Compared to this, a quick, half-hour wash requires the same amount of water and it has to be heated up quickly, using more energy.” As a rule of thumb, you can’t go wrong with the economy setting; it is designed to save water and energy.

The same is true of washing machines. By shortening the length of the cycle, you are upping the intensity of the wash so that it requires more resources to do the job in less time. According to Miele, there is also the fact that clothes need to be in detergent for more than half an hour for it to do its job. While Miele is supporting Ariel’s campaign to save energy by washing clothes at 30 degrees, it suggests doing a maintenance cycle every eight weeks. This means running an empty cycle at high temperature (over 75 degrees) to get rid of gunk building up in the machine that isn’t broken down at a lower temperature. This strikes me as ungreen and I’d suggest doing it less often, every six months perhaps.

For Anna’s e-mail address and eco-blog, log on to timesonline.co.uk/ecoworrier

Air-con or open window? It’s not a simple choice

Last week I mentioned a government guide that points out that air-conditioning increases fuel consumption in cars. I suggested opening the windows, a simple green solution to staying cool on long car journeys.

Well, it’s good to know you are all paying attention. No sooner had the words been printed, than I got several e-mails from readers asking whether driving with the windows down wouldn’t also drive up fuel consumption by making cars less aerodynamic.

I went back to the Department for Transport, who checked with the report’s researchers, who consulted a report for the European Commission on eco-driving (treatise.eu.com). The verdict was this: when you are driving at slow speeds, having the windows open is more fuel-efficient than using the air-con. Once you are doing speeds of 50mph or more, you should keep the windows closed, even if that means using air-conditioning.

It emphasises that it also depends on how aerodynamic your vehicle is in the first place. Hopefully that has cut the chance of bickering during hot summer road trips.

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