7. FoE: Waste burn ‘not green’ 

Incineration of domestic waste can produce up to 33% more greenhouse gas than burning gas in power stations, according to a study commissioned by Friends of the Earth ‘A Changing Climate for Energy from Waste?’ prepared by Eunomia Research & Consulting. ‘The government and waste industry must stop peddling the myth that waste incineration is green energy’, said Michael Warhurst of FOE. “The government must make it clear that they will not support the building of such polluting plants; using these incinerators to produce energy will undermine government attempts to tackle climate change.  Ministers must back truly renewable energy sources instead.”

The report notes that coal-fired generating stations in the UK emit more than 800g of CO2 for every kWh of electricity, while oil-fired stations emit 770 and gas-fired facilities emit less than 400g per kWh. However an incinerator that generates electricity emits 500g- although a heat-only incinerator emits 300g, while a Combined Heat and Power incinerator emits less than 350g per kWh. But there are very few of these more efficient lower carbon plants in operation. and FOE conclude that, depending on the source of energy being displaced by EFW, “there may be no net climate-related benefit associated with the generation of electricity from incineration, and indeed, there may be negative consequences for climate change”.

This poor showing for incineration is despite the fact that some of the waste is of biological origin, which means that the CO2 released on combustion had actually been absorbed from the atmosphere earlier- so overall this fraction is greenhouse neutral.  That’s why a proportion of the energy from incineration is sometimes seen as ‘green’. What FoE says is that this in fact in not completely true- since the carbon dioxide released by combustions can spend 100 years or so in the atmosphere and ‘the atmosphere does not, after all, distinguish between molecules of GHGs depending on their origin’.  So they claim ‘In its current, conventional form, life-cycle assessment is not a reliable indicator of the contribution of waste treatments to climate change’.

Moreover, they seem to argue in favour of land fill gas, contrasting  ‘landfilling biogenic carbon, in which process, biogenic carbon stays in the ground over a period of many years, to incinerating it, a process which liberates the vast majority of biogenic carbon as CO2 immediately’.  The point is that around 30% of the carbon is expected to be trapped in the landfill whereas it is all released by combustion- and the situation will worsen due to a higher percentage of fossil-fuel derived and decidedly non-green plastics in the waste burnt by incinerators.

Overall though, the focus is on suggesting that waste combustion is not always as green as claimed. By contrast the study says the UK could invest in a ‘real renewable energy-from-waste technology’, anaerobic digestion, to convert kitchen and commercial food waste into methane that can be burned and the resulting residue used as compost.