A large new incinerator to dispose of rubbish is needed because flats have “lower recycling rates than houses”, north London’s waste authority has argued.

Anti-incinerator campaigners contend that if north London’s household recycling rate improves, waste will have to be brought in from other parts of the country to keep the new incinerator running.

According to the North London Waste Authority’s (NLWA) plans, the new Edmonton incinerator would suffer from “significant technical issues” if it has less than 490,000 tonnes of waste to burn each year, only 100,000 tonnes less than north London produced in 2020/21.

Figures published by the Department for Environment, Food & Rural Affairs (DEFRA), estimate that recycling in NLWA boroughs is no more than 25-33%, well below the national target of 50% by 2020.

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When approached for comment on what would happen if improved recycling rates cut off the incinerator’s local supply of rubbish, the NLWA posted a statement on its website arguing its forecasts show “increased capacity is needed” to cope with local energy demand and increased waste. 

The statement added: “Even in the most ambitious scenario, achieving 65% recycling and a 50% reduction in food waste, London would still have a shortfall in energy from waste capacity if the [North London Heat and Power Project] is not built as soon as London’s old plants retire, which is expected in the mid-2030s.

“This is because the population in north London is expected to rise between 10-45%, with growth mainly in flats and apartments which have a lower recycling rate than houses.

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“We expect that people will recycle more and produce less waste in the future but overall, there will be more people producing waste, which means we need to plan for increasing volumes of waste.”

“If society moves more quickly to a circular economy, we can modify the facility to continue operating at lower volumes, so there is no need for us to take in external waste from other areas.”

Furthermore, the authority said its waste capacity estimates do not include commercial and business waste, which is “currently treated elsewhere”.

A report produced for the NLWA committee members who approved the new incinerator also highlighted the authority’s “power supply obligations” locally.

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This includes Edmonton Council’s wholly-owned heat network company Energetik, and Ark, who run a nearby data centre.

The NLWA has previously argued that it has “no plans” to source waste from outside the seven London boroughs that control it.

Another option to reduce capacity is that the incinerator turns one of its two “process lines” off, halving its capacity to 350,000 tonnes a year.

A needs assessment for the new incinerator, published by the NLWA in 2015, found recycling rates in flats was “typically around 10 per cent or less” due to space restrictions, building design and a “transient” population. 

The report added: “Going forward the proportion of high density housing is expected to increase in line with the London Plan. The increasing numbers of flatted properties in north London will mean the challenge of achieving a 50 per cent recycling target will be increased.

“The transient population presents further difficulties for local authorities wishing to communicate the need for improved recycling and waste prevention in the form of increased costs associated with communication budgets and increased recycling contamination rates.”

Looking at European cities that are more successful at recycling, the 2015 report cited ‘pay as you throw’ schemes and fines or charges as being effective at improving people’s behaviour.

The report added: “Although the context and policy environment of these cities is different to London they help to illustrate that whilst higher recycling rates than those currently achieved by the constituent boroughs are practically possible, levels above 50 per cent are likely to be challenging given current technologies, the socio-economic/demographic context of north London and the existing policy regime.”