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Have an energy-neutral Christmas

It needn't all be rampant consumerism and gleeful gluttony this Christmas. With a bit of thought we can embrace the waste and sort, clean, extrude and process our way to a greener future.

Every year, the British public celebrates Jesus's birthday by cutting down eight million trees, wrapping enough presents to smother Guernsey, binning billions of greetings cards, and then throwing away £1bn worth of food.

The UK spends more than any other European nation on Christmas, making it far more than just a one-off religious holiday. Extending from Bonfire Night well into the New Year, the Christmas season has turned into an orgy of rampant consumerism and gleeful gluttony that has environmentalists crying 'Bah! Humbug!'.

Greenpeace, for instance, notes that producing 1kg of wrapping paper takes 1.3kg of coal and emits 3.5kg of CO2, plus the impact of packaging and transportation. Its recommendation? 'Why not use newspaper?'

Meanwhile, researchers at the University of Manchester have calculated that Christmas dinners enjoyed by UK families each year have the same carbon footprint as 6,000 car trips around the world - with cranberry sauce alone accounting for half the food miles.

The most tangible result of our seasonal excess is rubbish: three million tonnes of it spilling out from bins in January. The good news is that Britons are slowly becoming less wasteful. The UK's 'peak rubbish' year was 2005-2006, when we generated nearly 25.5 million tonnes of household waste. The latest figure is down to 23.6 million tonnes and declining by a few per cent every year. We are also getting better at recycling, with a nationwide rate of nearly 40 per cent - and up to 50 per cent in the East of England.

But there is little room for complacency. The UK languishes halfway down the Euro league table for waste, far behind countries like Germany and the Netherlands that send almost nothing to landfill. We also have some collective blind spots, including those perennial Christmas accessories: batteries.

The UK uses more primary batteries (non-rechargeable alkaline cells) than anywhere else in Europe, and 40 per cent of annual sales occur in December. The average Brit will buy ten batteries to feed the flood of toys and gadgets unwrapped on Christmas morning. Just 2 per cent of batteries were recycled in 2009, with half the population simply chucking dead ones in the bin and nearly a third claiming ignorance that batteries could even be recycled.

In fact, alkaline manganese and zinc carbon batteries, which account for around 70 per cent of the market, are fairly easily recycled. The process recovers zinc, manganese and steel, as well as carbon to help in smelting. Rechargeable batteries can also be recycled, although currently most are sent abroad for that.

Rechargeable batteries are clearly the most eco-friendly choice for portable power but even they have their downsides. The demand for rechargeables has led to an increase in the environmental impact of mining and refining of nickel, cadmium, iron and rare earth metals. For instance, while NiMH rechargeables have a higher energy density than NiCd batteries and suffer no memory effect, they require over 10 per cent more nickel.

The EU Batteries Directive has set recycling targets of 25 per cent of all batteries by next year, rising to 45 per cent in 2016. If - or more likely when - the UK fails to meet them, it could face 'effective, proportionate and dissuasive' EU fines.

Britain has made more progress when it comes to recycling high-tech gifts. The recycling of unwanted gizmos, also known as WEEE (Waste Electrical and Electronic Equipment), is now well established. WEEE is now the fastest growing waste stream in the developed world, expanding at three times the rate of other rubbish. The UK had a WEEE collection rate of over 38 per cent in 2010, recycling 7.5kg of consumer electronics per person, well above the EU target of 4kg.

Flat-screen hazards

Again, though, there are exceptions. If you want to replace your LCD television, perhaps with a larger or 3D version, there is currently no automated process to recycle it safely and economically. Toxic mercury in the cold compact fluorescent lamp (CCFL) backlights means that most of today's flat screens must be considered hazardous waste.

WRAP (Waste & Resource Action Programme) is the government-funded non-profit company for waste strategy. Over the last few years, it has been investigating the volume recycling of flat panel displays. It concluded that any commercially viable option would have to avoid the manual removal of the offending backlights, a slow, expensive procedure that exposes workers to unacceptable levels of mercury.

Instead, WRAP proposes powerful shredder units fitted with extraction and containment systems, sealed so that mercury cannot escape. But questions remain. None of the washing processes attempted by WRAP under laboratory conditions were able to remove more than about half the mercury in the shredded material, thus leaving a dangerously contaminated residue. Moreover, while magnetic, eddy current and X-ray sorters could separate metals and glass, near-infrared devices proved unable to cope with either black plastics or the range of polymers found inside today's TVs.

The CCFL problem isn't going away anytime soon. The fourth quarter of 2010 saw a record 70 million flatscreen TVs sold worldwide, and similar figures are expected this Christmas. WRAP predicts that CCFL waste will more than double, peaking at 120,000t in 2016, before LED backlights and other technologies gradually supplant it.

The Christmas menu

If pricey gadgets top our collective Christmas list - accountants Deloitte's estimate the average UK family spent £803 on gifts last year - food and drink, at £365, are not far behind. Big supermarket chains and many grocery brands signed up to the Courtauld Commitment back in 2005. This voluntary agreement aims to reduce the impact of packaging, improve supply chain efficiencies, and cut down on food waste. It has already eliminated around half a million tonnes of packaging and is now focusing on reducing the carbon footprint of supply chains.

For example, the UK is the world's largest importer of wine. Not only do we ship millions of bottles of plonk all the way from Australia, Argentina, California and New Zealand, we then generate a massive surplus of recycled green glass, much of which is re-exported. In a two-year project called GlassRite, the wine industry began shipping foreign wines into the UK in bulk 'flexitanks' - essentially enormous toughened balloons.

Where a standard shipping container used to hold 12,000 glass bottles, it can now transport the equivalent of 32,000 bottles in a flexitank. Flexitanks have the added benefit of greater thermal inertia, helping to avoid unwanted temperature shocks to the wine en route. Over 200 million bottles of wine are shipped by flexitank and bottled in the UK each year, soaking up 24,000t of our recycled glass mountain and cutting our Yuletide booze miles to the tune of over 20,000t of CO2.

Soft drinks haven't escaped the efficiency drive, says Nicola Jenkin of WRAP: 'We found we could lightweight the top and bottom of aluminium cans. All Coke cans now weigh 5 per cent less than two years ago. We can even reduce them by another 5 per cent without them bursting in your bag.'

Supermarkets continue to reduce their environmental impact, and British retailers are among the greenest in the world. Ethical Consumer picked out Marks & Spencer and Co-op as the best places to source your Christmas dinner, highlighting such policies as the Co-op's target of 98 per cent renewable electricity in its 5,500 shops.

Tesco claims to be the largest recycler of cardboard in the UK and says it has sent no waste 'directly' to landfill since 2009. Sainsbury's promises to send no waste at all to landfill by 2020. While no supermarket can control what shoppers do after leaving the shop, incentive schemes, such as Tesco's Green Clubcard, hand out points (a billion in the UK annually) to people reusing bags or recycling mobile phones and expired inkjet cartridges. Some Tesco supermarkets even have automatic recycling machines that dish out one point, worth 1p, for every two aluminium cans deposited ' along with a readout of the emissions saved (see panel).

Machine vision

However, getting consumers to recycle is only one step towards reducing landfill. Waste processors are under pressure to recycle a wider variety of materials. Machines for sorting plastics rely on near-infrared (NIR) technology to sort polyethylene terephthalate (PET) containers from those made out of high-density polyethylene (HDPE). PET can be crushed, washed and reprocessed into polyester fibres for clothing or new PET bottles.

Recycled HDPE plastic has the highest value if it can be reused for food-grade containers, but NIR sorters cannot detect whether a bottle held milk or bleach, for example. Researchers at the Department of Bioengineering, Imperial College London, are using machine vision to determine whether a bottle can be safely reused.

They use a high-speed video camera to scan plastic HDPE bottles arriving at a recycling centre in Essex. The system compares the label on a bottle to a database of products on sale in the UK. If the system recognises the label as a foodstuff, the bottle is passed. If it cannot see the label or identify the brand, the bottle is rejected. After collecting around 120,000 frames of data, the system was able to sort HDPE bottles with an accuracy of around 75 per cent ' including bottles that had been severely distorted.

Even trickier to recycle are plastic films such as wrappings and scrap carrier bags. Half of all Europe's food, including virtually every supermarket turkey, is packaged in plastics, adding up to five million tonnes every year. Until now, plastic film has been difficult to collect or sort and usually ended up in landfill.

This summer, WRAP and recycling consultancy Nextek experimented to see whether mixed, contaminated plastic films could be economically recycled. After wading through countless bags of rubbish, they found that plastic films could be compressed, cleaned, dried and extruded to produce tiny black pellets with a value of £450 per tonne. Researchers noted that the product had 'a scent more similar to processed plastic than sewage' and was tough enough to be formed into thick moulded parts.

What about those inevitable Boxing Day leftovers? More than half of UK households say that they throw away food because they cooked too much, and 60 per cent admit to chucking food beyond its 'use by' date. Almost 20 million tonnes of food waste is generated each year in Britain, with nearly three-quarters ending up in landfill.

Composting, either at home or at municipal facilities, is the traditional disposal method for scraps, but it can't cope with the sheer volume of organic waste produced by UK agriculture and food production. One alternative is anaerobic digestion (AD). AD is a natural process that uses micro-organisms to break down organic matter, without oxygen, into a mixture of methane and carbon dioxide known as biogas, plus a nitrogen-rich digestate.

Biogas can be burned to produce heat or cleaned for use as a gas replacement or vehicle fuel. The government is making £10m available to stimulate investment in AD. Adnams Brewery in Suffolk is the first brewery to use its waste barley to produce enough biogas to power its delivery lorries.

Such muck into brass transformations are impressive, but perhaps not as impressive as turning muck into aluminium - or even platinum. Patrick Atkins, the director of energy innovation at Alcoa, says that US landfills now contain more aluminium than we can produce by mining virgin ores. The commercial viability of exploiting them depends on the fluctuating price of commodities, however, and landfills require several decades of natural decomposition before they can be safely exploited.

An eco-conscious Christmas

It seems the way of the future then is not to avoid waste but to embrace it, to celebrate it. A green Christmas doesn't mean totting up every last food mile or feeling guilty about tying a bow on your children's presents. It means realising that your home represents one brief stop on a long, and hopefully circular, journey for anything you buy, and making decisions accordingly.

Eco-conscious party-goers should choose products that are local or that have already been recycled, buy no more than they need, and support organisations that are trying to close the waste loop.

This year, inebriate households can even strive to make their celebrations completely energy-neutral. Adnams says that the waste from brewing a mere 600 pints of beer will generate enough biogas to heat one home on Christmas Day. And enough headaches to last well into 2012. *

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