Courtesy : stnicks.org.uk

Incineration and landfill

There’s been a lot of publicity recently about the closure of Harewood Whinn (read more here) so our Waste and Recycling Manager Sam Taylor has decided to compare landfill and incineration.

A landfill site image courtesy of WRAP

In York your waste is no longer sent to landfill, instead it is sent to Allerton Waste Recovery Park where it undergoes a number of processes (see what happens here). Most of what’s left is burnt to produce energy from waste. On paper this looks quite good – Amey who run Allerton WRP claims that they are reducing the amount of waste going to landfill in the county by 90% (Reference) But what impacts are there from burning and is it actually better than continuing to send our waste to landfill?

Land use:

Energy from waste plants (EFWs – aka incinerators) take up a considerable amount of space, though generally significantly less than a landfill site would. You have the same factors to consider during placement such as noise and air pollution to nearby residents, traffic management. What is often not realised is that EFWs do produce residual ash that is disposed of in landfill – so we still need landfill sites (ref).

Land is getting harder to come by and is therefore expensive, landfills don’t decrease the volume of the waste they contain so do require more space. EFW sites can reduce 2000lbs of waste down to 600lbs of ash so there is obvious space saving advantages (ref).

Emissions:

Wagons delivering household waste to both landfill sites and EFW plants have a similar impact on carbon emissions subject to the total distance the waste is transported which can vary greatly.

EFW are significantly more efficient than they once were but still are on average 40% less efficient at producing energy than burning gas in modern generator systems (ref); unless they also recover heat which Allerton Park doesn’t. EFW plants also generate 65% more carbon dioxide (CO2) than generator systems (ref) and more CO2 per unit of electricity than coal (Ref & Ref). Burning plastics has also been proven to release dioxins, furans, styrene gases (Ref) though if burnt at higher temperatures these health hazards are less likely (Ref).

Of course, landfills generate methane – a more powerful greenhouse gas than CO2  – due to biodegradable waste going in and decomposing without oxygen. Parts of this can be extracted and burnt to generate electricity but the amount has been falling steadily for the last 6 years (Ref). This is thought to be as a result of reduced gas yields which increases the cost of extraction and eventually makes it economically unviable. In 2011 landfilling was estimated to generate most of the 3% of carbon emissions that waste management accounted for in the UK but emissions from the waste sector had actually decreased by 64% since 1990, mainly thanks to diversion of biodegradable waste away from landfill (Ref).

Long-term impact

On the face of it, one might think that burning waste is better than landfilling because it requires less space and may lead to fewer emissions. It certainly gets rid of what’s perceived as a problem – waste – very quickly. Yet, when looking at a long-term picture quick solutions are not always the best. Waste is just a derogatory term for resources, which have been dwindling with the exception of renewable ones. Burning things like plastics means those fossil fuel-based materials are lost forever and definitely contribute to climate change. Burying them in landfill can be seen as carbon sequestration instead of what some people term as “skyfilling”.

The biggest objection to incineration/EfW is its disincentivising impact on zero waste and circular economy efforts which must be our end goal to achieve true sustainability. The plants require lots of finance and guaranteed high volumes of materials to continually burn for twenty or more years. This greatly undermines both local and national efforts to reduce waste in the first place.

So landfill costs less than burning waste even when you don’t include the cost of sending toxic bottom ash to specialist landfill sites, though EFW sites take up less space, they do tend to accept waste from a larger area resulting in more wagons making longer journeys. There’s also more risks of some very nasty substances getting into the air if the cleaning processes should fail.

As always I believe individuals need to take more responsibility and look at ways to cut down their waste in the first instance rather than relying on other people/governments and organisations working out what to do with it. We don’t have a choice about what happens to our waste once it’s gone into the bin so why not pay more attention to what we are generating in the first place?

Of course we are a tiny bit biased – we wouldn’t have St Nicks without the former Tang Hall Tip!