What about China?

Qu: Would it be possible to put waste, i.e. bio-degradable rubbish and sewage into an air-tight container, let it produce methane gas, siphon it off to cook with and power gas-fired central heating, filter off the water, and be left with compost to put on gardens?

Yes – very possible, in fact it’s already being done. It’s called Anaerobic Digestion and the process is widely used to treat wastewater sludges and organic wastes. Anaerobic digestion can reduce the emission of harmful landfill gases into the atmosphere and is a renewable energy source because the process produces a methane and carbon dioxide rich biogas suitable for energy production. Also, as the question suggests, the nutrient-rich solids left after digestion can be used as fertiliser.

So why isn’t this process used everywhere? Anaerobic digesters require a high level of technical expertise to maintain as careful control of the digestion temperature, pH, quality of input and loading rates is crucial. Because of these complexities, despite being recognised by United Nations Development Programme as one of the most useful decentralised sources of energy supply and being less expensive to run than large powerplants, anaerobic digesters are not widely used in industry. (source)

Anaerobic Bioreactors, a type of landfill, can also transform decomposing material into an energy source. By removing oxygen and pumping lechtate (water which has collected waste products from the decomposing matter) and other liquids around the bioreactor the waste produces methane, which can be collected and used instead of fossil fuels. (source)

Perhaps the most exciting and accessible use of the anaerobic production of methane from plant waste is the ‘pyrolysis unit’ – invented for domestic use in India by Ravi Kumar. A family collects waste plants, dries then and puts them into the unit’s circular casing. This casing is sealed to stop oxygen combining with CO2. A small fire is started in the central void; this heats up the plants and causes them to emit gases through small holes in the casing. The gases ignite and burn for long enough to cook dinner (about an hour). Then, brilliantly, the remaining charcoal can be raked out and used as fertiliser – what’s more the soil’s subsequent ability to lock in carbon dioxide also increases. (James Bruges – What About China?- p19)

Hope that helps, 

Bethan

Qu: Having read your answer on the effect of patio heaters (last bastion of the smoker) on global warming I wondered what the effect of the 6 billion cigarettes smoked annually around the world has on the global environment?

Oh dear, this answer sure ‘ain’t pretty. Now I’m really going to have to disown all my still-fag-smoking now ex-mates. 

Let the anti-ciggie tirade begin! Starting at the end and working backwards seems appropriate as cigarettes are most obviously harmful to the environment when discarded, marring the view as they lie scattered beneath the fore mentioned patio heaters. 

Sadly, cigarette butts are most often than not thrown to the floor and left as litter.  It is estimated that over 4.5 trillion cigarette butts are irresponsibly disposed of annually, making them the most littered item in the world. 

There seems to be a general consensus (ask any smoker) that cigarettes are bio-degradable over a 25 year period– however this figure is debatable and some experts doubt that the filters will ever degrade. Even as they break down cigarettes are harmful as they release the 4,000 chemicals that they contain, contaminating the soil or rivers, lakes and ocean that they are washed into. Wildlife is also affected as these toxins enter the food chain and many creatures fatally consume the indigestible fibers. Cigarette packaging is often littered as well; in the UK alone, each day, 122 tonnes of cigarette related debris is thrown out.

As they are smoked they are an environmental nuisance, as 90% of their smoke gets into the atmosphere, adding to air pollution (remember the days that you couldn’t even see to the bar when you walked into your local) and having a negative impact on the health of anyone nearby. 

If you think all that is bad then wait till you hear about the environmental impact of cigarettes. It is estimated that up to 200 000 hectares, usually in the developing world, are cleared to make room for tobacco farming every year. The sensitive tobacco plants are then treated with a nasty cocktail of fertilizers, pesticides and herbicides to protect them from insects and disease. Tobacco farms are often by villages and, when the chemicals inevitably leak into the soil, they begin to poison the waterways, ecological systems, crops, and livestock in the surrounding communities.  Tobacco uses more nutrients than several other crops, and this quickly degrades the surrounding soil.  It is also believed that the toxic chemicals may indirectly cause the development of pesticide-resistant mosquitoes and flies.      

Living by a tobacco farm is no fun then, but this gets a whole lot worse if you’re unlucky enough to be one of the workers harvesting the plants. When the wet leaves are picked nicotine can be absorbed through the skin resulting in nicotine poisoning.  This ‘green tobacco sickness’ causes dizziness, nausea, vomiting and breathing difficulties and affects 41% of workers every season. 

On top of the land clearance for tobacco planting we must also take into account the trees that are felled to process the leaves and to produce the wrapping and packaging for cigarettes. Nearly one hectare of forest is needed to dry every hectare of tobacco meaning that over 600 million trees are destroyed annually for this purpose. On top of that six kilometers of paper is used per hour by the machines that roll and package cigarettes! 

And then there is tobacco’s contribution to world hunger. According to Dr Judith MacKay, Director of the Asian Consultancy on Tobacco Control in Hong Kong, tobacco’s “minor” use of land denies 10 to 20 million people of food. 

Anyone fancy popping out for a smoke? Didn’t think so!

Bethan

Thanks to these links for the above information.

http://www.smokefreecalgary.com/bins/content_page.asp?cid=3-119&lang=1 
http://www.litterbutt.com/
http://?www.aadac.com/87_447.asp?
http://tobaccofreekids.org/campaign/global/pdf/ag2.pdf
http://?www.hpb.gov.sg/hpb/default.asp?pg_id=865&aid=105
http://?www.cigarettelitter.org
http://www.ci.berkeley.ca.us/publichealth/tobacco/environ.html?
http://www.ash.org.uk/html/international/html/environment.html?http://www.longwood.edu/cleanva/cigarettelitterhome.html

Qu: What’s your stance on energy saving light bulbs? I’ve heard several reports that they contain mercury and can be dangerous.

The media had a field day at the end of last year with some serious scaremongering regarding the dangers of energy-saving bulbs (CFL’s).

It all began when The Daily Mail picked up on a report by the Environment agency calling for a public awareness campaign to explain that the packaging of energy-efficient lighting contains small amounts of potentially toxic mercury and should therefore be disposed of with care.

The Mail ran a typically hysterical piece headlined “An energy saving bulb has gone - evacuate the room now!”

The general thrust of the article being, ‘energy-saving light bulbs are so dangerous that everyone must leave the room for at least 15 minutes if one falls to the floor and breaks.’

This is, of course, an exaggeration of the facts. Toxicologist Dr. David Ray, from the University of Nottingham, told the BBC that 6-8mg of mercury is present in a typical low-energy bulb. A pretty small amount considering thermometers, which we happily stick in our mouths, contain about 3 grams of the stuff.

Dr. Ray concludes that a smashed bulb causes little danger - but warns that this increases proportionately to consistent exposure and greater numbers of smashed bulbs. DEFRA also played down the threat to health, saying; ‘No amount of mercury is good for you, but the very small amount contained in a single modern CFL is unlikely to cause any harm, even if the lamp should be broken,’

(It’s also worth noting that strip lighting has always contained mercury - yet no-one seems to be complaining about that!)

The Mail went on to finger energy-saving bulbs as a potential source of cancer following a report by British Association of Dermatologists (BAD).

In this next distortion of the facts they claim that the ‘new’ lights (they’ve actually been around for over 30 years) “can trigger migraines, as well as dizziness, loss of focus and discomfort.” However the article goes on to say that these symptoms would only affect people already suffering from certain conditions (like epilepsy and photosensitivity). Dr Colin Holden from B.A.D. explains that people suffering from photosensitive skin conditions should be allowed to continue to use daylight (tungsten) bulbs to prevent “photosensitive eruptions ranging from disabling eczema-like reactions, to light sensitivities that can lead to skin cancer.”

Fine, those with a medical condition would obviously be prescribed the old bulbs, but that shouldn’t stop everyone else switching to CFL’s.

The real concern, the one that started this debate in the first place, is the environmental impact of disposing of the energy-saving bulbs. The Environment Agency’s call for a public information campaign acknowledges a need for greater awareness before tungsten bulbs are completely phased out. Careful disposal of the energy-saving bulbs will prevent the mercury content being released into the atmosphere. Thankfully more and more places now provide the facilities for you to drop off your used bulbs to be disposed of safely, including council refuse tips and some bulb retailers (Ikea, DIY stores etc.) and this service will become more widespread as CLF bulbs become more popular.

Besides, it’s reported that, even if everyone just threw their CFL light bulbs into the main rubbish to go to landfill, the amount of mercury entering the environment would still be less than that which currently enters the environment as a result of the production of the electricity needed to power all the traditional lightbulbs. Besides, CFL bulbs last far longer than traditional ones so there will be far less of them to throw away (source). So, no excuses, off you pop to the shops to buy your new bulbs…

Bethan

One of the key issues at the recent G8 summit was the global increase in the cost of food. As discussed previously, the rising price of staple foods has been linked to the increased cost of oil, which has caused land previously used for food crops to be turned over to crops for bio-fuels.

At the summit in Japan, the World Bank President Robert Zoellick highlighted the growing food shortage and urged the US and ‘rich countries’ in the EU to reform their bio-fuels policies and concentrate on food production. All well and good but it’s hard to believe all this talk is going do much to curb the rate at which your weekly shopping bill is creeping up, especially considering the frequency of missed G8 targets.

But we’re not as helpless as we imagine, the average consumer might not be able to dictate how farmers use their land but we can make sensible choices when it comes to dinner time. You’d think, with the increased prices, that people would be making an effort to make each meal count, but a recent survey estimates the average UK household throws away £8 of leftovers a week and each year in the UK as a whole wastes 4 million tonnes of food. People are spending about 9% of their income on food, with poorer households forking out up to 15% of theirs on staple foods such as milk, eggs and bread - foods that have been hit hardest by price increases in recent months.

This week Gordon Brown urged Britons to stop wasting food and to avoid making unnecessary purchases. But it’s not just the consumers who need to change their habits, the government might be more successful in reducing waste if they tackled supermarkets directly. The Liberal Democrats environment spokesman Steve Webb, blamed the governments “cosy” relationship with supermarkets for their failure to change policies which make it harder for householders to avoid food waste: “They refuse to stock small portions, which are essential for the growing number of one-person households, and offer too many buy-one-get-one-free deals on perishable goods.” Supermarkets also account for a large percentage of waste and throw away large quantities of edible food through poor stock management.

So, what can you do? Try planning your evening meals for the week and using up tins you’ve shoved to the back of the cupboard. Making extra in the evening means you take care of lunch the next day too - and this saves on energy, as you won’t be turning the cooker on again. Cooking for more people always works out more economically so offer to cook for your flatmates or friends and get them to return the favour another night. You can also try avoiding supermarkets; they might seem cheaper at first but in the long term it means smaller shops can’t survive or have to put their prices up further. If you do have to go to the supermarket write a list and stick to it - don’t be tempted by offers which will leave you with a fridge full of out of date food.

Bethan

Qu: To what extent will reductions in carbon emissions in the UK as a result of greener cleaner technologies be compromised by predicted world population growth of (according to a study by the U.N) a further 2.5 billion souls by the 2050?

Good question, and one that seems to be ignored in the general media hype surrounding climate change. Everywhere you look media channels and big business alike are out to persuade individuals to ‘do their bit’ by reducing their personal CO2 emissions. All well and good and as an empowering strategy to positively impact climate change but one that starts to look more like a convenient marketing strategy when you consider predicted population growth. The sad fact is that unless we do something drastic out-of-control population growth will wipe out the gains by even the most ambitious conservation and recycling schemes.

As John Feeney, writing for The Guardian, points out: “To avert catastrophe, we need to reduce both factors in the equation: our numbers and per person consumption.”

Yet the population issue is routinely overlooked. Feeney goes on to highlight the work of the Global Footprint Network (GFN), which tells us that, given the current population, each person has an allowance of just under 1.8 gha (global hectares of biologically productive land and sea) to maintain a sustainable global footprint. Given our current average of 2.2 gha per person we are exceeding the earth’s limits by 25%.

The GFN calculate that a drop in consumption to 1.8gha per person in the UK would involve a reduction in consumption to match level of Uzbekistan. Globally this would mean radically raising or reducing the living standards of some countries not a very realistic prospect.

?And these stats don’t take into consideration the UN’s projected increase in population of 40% by the middle of next Century. Compensating for the rise would mean shrinking the global footprint to under 1.3 gha, roughly the level of Guatemala or Nigeria. Again - not a vision of the future I’d put my money on being realized.

Although it is important to do your best to minimize personal contribution to global consumption it’s equally useful to be aware of the issues involved. In the face of the UN’s predictions population is a very real factor in the climate change debate and should be treated as such by governments and the media.

Bethan

Further reading & useful sites:

The Optimum Population Trust
Sustainable Population blog

Qu: If turning off appliances, recycling etc. are just a drop in the ocean; is there any point doing them at all?

With all the media hype, the threat of peak oil and messages of impending catastrophe for the planet, I don’t blame you for feeling over faced. Ultimately global change will happen quickest if instigated by global leaders. Once out of the ground fossil fuels will be used and harmful pollutants emitted. Politicians must devise and implement policies that reduce the amount of coal, gas and oil extracted within, or imported into a country. The sad truth is that if leaders don’t control the amount of fossil fuels at source all our attempts to reduce emissions in a hundred little ways make a very small impact on the overall situation.

However, that doesn’t mean your efforts are useless. Every little does help, so keep up your recycling, turn of those appliance and encourage others to do the same. You can also use your vote to influence the way the government prioritises. Politicians won’t change unless the public puts pressure on them. If you don’t then it’s left to corporate lobbyists, who can twist legislation to ensure that corporate interests are served. As James Bruges writes in What About China? A new wave of thinking suggests that the solution must involve individuals.The atmosphere does not belong to corporations - not even to governments or countries. We all, as individuals, have an equal right to its life-maintaining properties.

Instead of getting demoralized find out who your local MP is and urge then to put a cap on the use of fossil fuels. Get inspired about what you can do by learning more about the transition town movement, where communities are successfully working together to find a post-carbon way of living.

Bethan

Qu: I’ve heard that patio heaters are worse than trans-Atlantic flight for carbon emissions. Can this be true?

Hmmm… I’ve heard this one before, it’s the kind of gloomy end-of-the-world rumour that people like to pontificate as they light up outside the pub under one of the offending appliances!

Patio heaters are obviously so wasteful, in that their job is essentially to heat the open air (!), that they are often held up as an example of societies improvident tendencies. It’s true; they are a complete waste of energy, but as a nation we have many much more wasteful habits which we choose to overlook so a bit of perspective is needed to answer the question.

The average UK patio heater has a consumption of 8.9 kilowatts (kw). That’s quite a lot for a ‘non-essential appliance’. In fact a patio heater turned on for an hour uses enough power to boil a kettle from cold 80 times. And 8.9kw is the average, but most of the, the ones smokers huddle under in pub gardens, emit 12kw or more - there are plenty of 15kw patio heaters out there.

They use bottled LPG (propane) for fuel and for every hour of use a 12kw heater emits 2.6Kg of CO2. (source)

So, how does that compare to the CO2 from a transatlantic flight? Well there’s quite a lot of variance depending on the carbon calculator you choose to use as the assumptions behind them differ - which isn’t very reassuring! For the sake of this question I’ve taken a middle of the road figure provided by CO2balance. This company quotes a distance of approx. 5586 km (return from London Heathrow to New York) and CO2 emissions of 2.54 tCO2 for one passenger.

Your flight would take approximately 7 hours, during which you would produce approx. 2540 kg CO2. Running your 12kw patio heater for the same amount of time will produce 18.2kg. So if you use time as a comparison your flight is much worse.

The answer really depends on your patio heater usage and how many flights you take. The Market Transformation Programme (MTP) who supply government stats report state that use of patio heaters by individuals is relatively low. It’s pubs and restaurants that make the most impact and with the smoking ban increasing the demand for cosy outdoor things are set to get worse.

Before the introduction of the smoking ban, MTP estimated 2006 emissions from heaters at 20.3 ktCO2. They’ve predicted that in the wake of the ban emissions could be between 141 and 282 ktCO2 annually. (yes, that’s KILO TONS). (source)

However before you go vigilante and start persecuting all those pubs trying to heat the world, it’s worth looking at the wider picture. The UK’s total production of CO2 in 2006, according to DEFRA, was 556.5 million tonnes, meaning that the patio heater’s share is negligible, even at the upper end of the MTP’s estimates. Passenger cars, on the other hand, accounted for a chunky 68.7 million tonnes and air travel is increasing every year - and being actively encouraged with the opening of the new Heathrow terminal.

My advice is to boycott the pubs that use the offending appliances (put a jumper if you want to be warm while you smoke), then start finding holiday destinations you can drive to - or even better, reach by train.

Bethan

Q: What exactly is the purpose of carbon trading? It seems to me it legitimates the use of carbon in the name of saving it.

Carbon or emission trading, sometimes known as cap and trade, is the name given to an administrative scheme used to control pollution by providing financial incentives to reduce CO2 emissions. Companies and other groups are given credits that represent the right to emit a specific amount, not exceeding a limit imposed by the government or central authority. If the company wants to emit more than their allowance they can buy credits from those who pollute less. (source)

So, the buyer is paying a charge for polluting, while the seller is being rewarded for having reduced emissions by more than was needed. The idea is to give an economic incentive to reduce emissions at the lowest possible cost to society.

Your scepticism about the scheme is shared by many experts who agree that trading emissions, as a solution to global warming is flawed with problems. Like you, some think that it is a way of allowing polluters in the developed world to shift the burden of making cuts onto factories in the developing world. As many of the companies receiving income from selling their credits then go on to spend it on expanding their factories, the emissions saving is cancelled out. Worse still, emissions trading may have set back the battle against climate change by diverting investment from long-term solutions such as renewable-energy technology.

In theory carbon trading presents real opportunities for new business approaches - an economic driver for a low carbon economy - but it’s a new field, market forces are yet to settle and there are problems with monitoring and enforcement.

As the director of Yale’s Center for Environmental Law and Policy, Dan Esty, says; “Carbon trading is a promising strategy for reducing greenhouse-gas emissions, but the current structures have serious flaws.” (source)

Given current appraisals of the scheme it is tempting to side with it’s detractors, who maintain that the only real winners in emissions trading have been polluting factory owners who can sell menial cuts for massive profits, and the brokers who pocket fees each time a company buys or sells credits.

Bethan

With diesel topping 120p per litre and a further 2p rise in fuel tax planned for the coming months, many companies reliant on road mobility are up in arms. Lorry drivers staged a protest this week, blocking the M4 from London to Cardiff. MP’s too have been protesting, against Alastair Darling’s proposed vehicle tax on older, inefficient models.

It seems that owning and running a car is only going to get more expensive - an additional household cost that is predicted to hit poorer families, long-distance commuters and SUV owners hardest.

But is it really such a bad thing? The government has pledged to reduce CO2 from cars by a third by 2030 and these price increases are a strong incentive for people to rethink their long-term reliance on cars and for companies to invest in energy efficient technologies.

That said, the situation is by no means an entirely positive one. Worryingly, the increase in fuel is a major contributor to a global food shortage, which is causing food price inflation to rocket.

“The food price rises are a result of record oil prices, US farmers switching out of cereals to grow biofuel crops, extreme weather and growing demand from countries India and China, the UN said yesterday.” (source).

A combination of increased oil and fuel prices paints a grim picture for the economy; now, more than ever, it’s time to rethink your habits, if only for the sake of your bank balance. Leave the car in the garage and jump on your bike for a start Got lots of heavy bags? Change of clothes? Gym kit? A laptop? No excuse - invest in some panniers and get pedaling. As for food prices - try planting some veges in your own garden - salad leaves like rocket and spinach can be expensive in those ready to wash packets from the supermarket but are surprisingly easy to grow - especially at this time of year. Buy locally produced food and be aware of what you use every week so you can avoid wastage. Easy!

Bethan

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