Where there’s muck, there’s … energy – energy from waste in a zero-waste society
For many centuries, waste was exactly that – an unwanted product that should be put out of sight and forgotten, buried in middens or landfills, thrown into the street or the river. Now concerns about the soaring amount of natural resources we are using and discarding have reclassified “waste” as a valuable raw material and forced recycling and waste management higher up the corporate and personal agenda. The UK Government has been part of that process too, although not always as a consistent or reliable supporter, governor or leader. James Nicholls, Managing Partner at Stephen George + Partners (SGP) takes a look at the opportunities and challenges of a new sector where SGP’s existing skills and experience are being applied with success.
Explains James: “It’s been a moveable feast. Energy from Waste (EfW) plants are long term investments and therefore need a stable context – market if you like – in which to operate. The Government needs to offer clear goals, policies and support to allow EfW to fulfil its role in sending less waste to landfill.”
DEFRA’s Waste Infrastructure Delivery Programme was established in 2006 to help the UK meet EU targets on reducing the amount of municipal waste (including recyclables) going into landfill to a maximum of 10% by 2030. The scheme was successful in giving financial support through PFIs to local authorities to fund waste infrastructure contracts with private sector suppliers. But in 2013, being on course to meet its targets, DEFRA withdrew funding to some schemes and switched its focus to delivering the greatest cost savings under the existing contracts.
And it’s clear the scheme in its original form was a success, but only a partial one. Currently, there are 40 municipal Energy from Waste plants in the UK, with nine more in construction. The proportion of local authority collected waste going to EfW plants increased from 9% in 2000/01 to 41% in 2017/18 (UK Government services and information (2018)) But according to the Environmental Services Association, the capacity gap for residual waste is forecast to be at least 3.5M-6Mt/y in 2030, even with supportive measures for recycling.
Continues James: “The Government is keen to extol EfW’s role in diverting resources from landfill. Its report, Our Waste, Our Resources: A Strategy for England (December 2018), talks easily of EfW’s role in achieving the Government’s target of reducing the amount of municipal solid waste (no recyclables) sent to landfill to no more than 10% of the total by 2035. Yet that same Government is leaving future capital investment to the private sector with no supportive policy framework to help. The private sector can see the opportunity – and are bringing new plants online, but lack of trust in the Government’s ability – or will – to provide a clear and forward-looking policy framework, is undermining the sector’s progress.”
There have been some concerns voiced that EfW plants will compete for “raw materials” with recycling schemes, undermining the push to recycle more. EfW companies are clear that EfW plants sit below recycling but above disposal in the waste hierarchy of prevention, reuse, recycling, recovery and disposal. And although EfW companies might be accused of “they would say that wouldn’t they”, experiences in Europe show that high rates of recycling, composting and energy from waste can and do coexist. Germany has the highest recycling rate in the world at 66% and incinerates 32% of its waste. Austria recycles 58% of its waste and incinerates 38%. This is because the energy recovery process has diverted non-recyclable waste from landfill rather than diverting recyclable waste from recycling.
The need is clear; the facilities proven and the private sector is already positively involved. But the Government needs to do more to unlock domestic infrastructure investment in EfW by creating a coherent, stable policy environment for recycling and resource management.
Designing for EfW projects
Energy from waste (EfW) plants take residual waste (i.e. the remaining waste that cannot be economically or practically reused or recycled) and thermally treat it, recovering energy in the form of electricity, heating and/or cooling, or conversion of the waste into a fuel for future use e.g. transport fuels, or a combination of these forms. The process of converting waste to energy is the primary driver for the design of the site and its buildings.
EfW plants are complex and exist in many different configurations, but can usually be broken down into four basic components:
- A reception area to receive the waste and prepare it for treatment, which can include sorting out any recyclable materials such metal or paper
- A thermal treatment – this essentially releases the energy from the waste
- Conversion to a transportable form of energy – electricity, heat, fuels
- Emissions clean up – ensuring waste gases are safe
SGP has applied many of the techniques it has honed in masterplanning logistics hubs and business parks to the design of EfW and recycling plants.
Explains Richard Smyth, Studio Director at SGP: “Back in 2006, when local authorities were actively seeking EfW contracts, one of the key criteria was the ability of the private partner to provide quality facilities to treat the waste – and design was actually a scorable part of the process.”
Getting an EfW plant through planning was – and still is – a major undertaking. Energy from Waste is a still a bit of a bogey-man – mention it and phantoms of pollutants, noise and unending traffic arise. But done well and carefully, an EfW plant can be no more annoying than a business park, and brings a lot more to the green economy.
The first concern is the site. Ideally it needs to be close to the users of the energy it creates or industrial users, as some plants generate electricity only whilst other generate both electricity and heat, referred to as Combined Heat & Power (CHP). The gross efficiency of electricity-only facilities is about 27%, but using a CHP unit can give overall efficiencies in excess of 40%. Many plants are already CHP-enabled but heat offtake is not common in the UK, unlike many other European countries. In the Nordic countries, for example, energy-from-waste plants are often sited in urban areas connected directly to the local heat grid. However, at SGP’s Millerhill in Edinburgh, the plant is expected to export up to 11MW of electricity to the National Grid plus supplying a maximum of 20MW to a district heating system.
Quite often EfW sites are in the open, in a field or on an old brownfield site, and are visible to the surrounding area. The closer to residential areas, the higher the number of complaints; making early and close consultation with locals and stakeholders vital to allay their concerns.
The buildings themselves are big – often seven or more storeys for the main plant room – but the design is outward looking. The envelope is wholly that – the wrapping for the process – and its main role is to minimize the visual and physical impact of the plant on its environment. SGP’s experience in designing large scale logistics units and manufacturing facilities provides transferrable expertise. This can be in the form of masterplanning the process and materials handling or the consideration of the materials, products, and colours used for the external envelope.
Traffic is one of the most commonly voiced concerns raised by residents and understandably so. It is expected, for example, that there will be on average approximately 105 waste deliveries and nine bulk loads removed from atypical waste transfer station site each day. So planning the flow into and out of the facility, as well as between processes within the site, are an important part of SGP’s task, and one where previous experience of designing business, logistics and retail parks is a valuable asset the practice can offer any waste management client.
Concludes Richard: “Although these projects are classed as the energy sector, I see these schemes as a natural extension of the skills we’ve honed in logistics, industrial and manufacturing sectors. The EfW and waste management sector has a lot of potential and the rule book is being rewritten all the time. With Brexit and lack of clear Government support, there are many challenges, but the sector is diverse and offers a lot of opportunities. To date many of the EfW plants have been large scale facilities, but evidence from places like Norway indicates smaller plants, closer to energy end users and where a whole community can benefit – make a lot of sense. Whatever the energy sector’s future, I’m looking forward to SGP being a part of it.”