LowCGen

How can recycling help combat climate change?

Recycling has many benefits including cost savings, reduced need for virgin materials and finite resources, lower demand for landfill space and reduced pollution. Equally important it can help in the fight against climate change…

Emissions from landfill

Disposing of waste in a landfill is the least desirable option both environmentally and economically. As waste decomposes gases and leachates are produced. Despite stringent controls on a landfill site, such as lining to prevent leakage and flaring to prevent the build up of landfill gas, many substances still escape into the surrounding environment

Greenhouse gases - In a landfill waste decomposes in airtight conditions and large amounts of landfill gas are emitted as a by-product of the process. Landfill gas is largely comprised of methane, a highly explosive greenhouse gas that is roughly 24 times more potent than carbon dioxide.

Excess landfill gas must be flared for safety reasons. However, it is estimated that up to 50% still escapes into the atmosphere. Landfill gas can continue to be emitted for some 30 years after closure of the landfill site (DEFRA, 2003).

Energy savings through recycling

Manufacturing goods from recycled materials can save huge amounts of energy, which in turn, reduces greenhouse gas emissions to the atmosphere. This is because the vast majority of energy is produced through burning fossil fuels such as coal and gas and the combustion process releases carbon dioxide.

• Producing recycled paper and aluminium cans reduces CO2 emissions by 95% compared to primary production.
• Producing recycled plastic carrier bags uses two thirds less energy and 90% less water than primary production (waste Online, 2008).

How does recycling compare to other methods of waste disposal?

A study by WRAP compared the environmental impacts of recycling, landfill and incineration with energy recovery. The life cycle analyses (LCA) of 8 different waste streams were compared for each method of disposal and it was found that 83% of the scenarios favoured recycling.

Relative greenhouse gas savings were also assessed and figures showed that recycling the waste streams saves 10-15 million tonnes of CO2 equivalents per year compared to landfill and incineration with energy recovery. This equates to taking 3.5 million cars off the UK roads! (WRAP, 2008).

What about organic waste?

Any organic waste that cannot be recycled should be composted either in the home,  at a centralised facility or in an anaerobic digester.

Composters - When organic waste decomposes in a composter it is mixed with plenty of oxygen. The by-product is carbon dioxide rather than methane so the relative greenhouse gas emissions are automatically reduced. The nutrient-rich compost produced can be fed back into the land.

Anaerobic Digester – In an anaerobic digester waste may be decomposed in airtight conditions to produce methane, which can then be captured and burned to produce electricity. The chemical processes that decompose the waste also produce a lot of excess heat energy, which could be used to heat nearby homes and businesses. If you have a compost heap in your garden you may have noticed the centre becomes very warm. In a digester the compost can reach very high temperatures up to 60C. Using this controlled method gases are far less likely to escape into the atmosphere than in a landfill and again the final product is a nutrient-rich compost.