focus:Technology Renewable energy technology update
New generation waste-to-energy
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N TERMS of the balance between the energy and resources we consume and the waste we produce, the world is fast approaching a tipping point. A new generation of energy from waste technologies can help, as Rolf Stein explains
As global waste levels rise and fossil fuel and raw material reserves decline, the world is facing a growing resource crisis. The coming decades will do little to relieve this problem: with the global population projected to rise to nine billion by 2050, energy requirements will rise significantly, while rising living standards in the developing world will lead to higher levels of waste being produced than ever before. In terms of the balance between the energy and resources we consume and the waste we produce, the world is fast approaching a tipping point. The solution to this combined energy and waste management challenge lies right on our doorstep – or rather, in our rubbish bins. Waste is a resource high in calorific value and rich in valuable materials,
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July/August 2012 | Renewable Energy Focus
with enormous potential as a source of energy. Too often this is literally wasted. Generally, waste material is consigned to landfill and little or no effort is made to utilise this energy or resource potential.
A viable alternative A new generation of energy from waste technologies have been developed which can convert waste into clean, renewable energy with minimal environmental impact whilst maximising resource recovery. In particular, Advanced Conversion Technologies (ACTs), which use residual, non-recyclable waste to produce a synthesis gas (syngas) which can then be used to generate electricity and other energy outputs, have the potential to combat rising waste levels while meeting the world’s need for a clean, safe energy supply.
These new and innovative waste to energy technologies allow for efficiencies which can compete with conventional sources of energy. In terms of electrical efficiency, by converting waste to a gas to generate electricity directly, ACTs dramatically improve energy conversion efficiency and maximise electrical output. For example, Advanced Plasma Power has developed a patented ACT – the Gasplasma process. This uses plasma arc technology to further purify the waste-derived gas, removing long-chain hydrocarbons and producing a very clean hydrogen rich ‘syngas’ which can be used directly in gas turbines or engines. Technologies such as this have transformed the energy from waste landscape and opened up a range of energy producing possibilities, from fuel cells to aviation fuel to a wastederived gas suitable for injection into the national gas grid. In addition to delivering a source of renewable energy, ACTs also have demonstrable benefits to the environment. Currently, much of the world’s waste is either buried in landfill or burned in incineration plants. Neither of these solutions is environmentally sustainable. Waste left to decompose in landfill releases high levels of methane, a very potent greenhouse gas which has been shown to contribute to global
About: Rolf Stein is CEO of UK-based Advanced Plasma Power, a leader in waste-to-energy and advanced fuels technology. Technology
warming; there is also a risk of land and groundwater contamination. Incineration is also not optimal environmentally. For instance, it produces around 20-25% ash. This requires transport, processing and disposal, raising costs and increasing waste’s carbon footprint. By diverting waste from landfill and mass burn incineration, ACTs reduce the impact of waste on the environment. Efficient waste to energy technologies can therefore contribute not only to our increasing energy needs, but help to maintain the environment too. These benefits can be felt in the developing world as much as the developed. Millions of the world’s poorest inhabitants are living alongside mountains of waste, detrimental both to their health and, through greenhouse gas emissions,
over to agriculture, housing or the community.
Global potential There is enormous potential for the global expansion of waste to energy technologies, and ACTs in particular. Governments around the world have set their own ambitious targets to reduce greenhouse gas emissions, minimise landfill and promote renewable energy generation. Advanced waste to energy technologies that process waste in an environmentally responsible way, while delivering low-carbon, renewable energy, are vital to meeting these targets. In the UK alone, wider use of ACTs to process waste can contribute to meeting several Government tar-
achieve 15% of its energy consumption from renewable sources by 2020. By diverting waste from landfill and instead using it as a feedstock in waste to energy plants, the UK can not only meets its commitments to reduce landfill levels, but it can also go a long way towards ‘greening’ its energy network. However, despite the enormous potential of these technologies to contribute to a lowwaste, low-carbon future, support is needed to encourage the investment required to expand waste to energy infrastructure. As a result of the financial crisis, current constraints in the banking sector present challenges to the renewable sector across the developed and developing worlds. Governments can help to redress this issue by put-
Technologies such as this have transformed the energy from waste landscape and opened up a range of energy producing possibilities to the environment. Disposing of waste using waste to energy technology could ease these environmental problems by reducing emissions, while land which might otherwise be used for landfill can be given
gets simultaneously. The EU Landfill Directive requires all EU Member states to reduce landfill waste by 65% of 1995 levels by 2020. At the same time, the 2009 Renewable Energy Directive sets a target for the UK to
Advanced Plasma Power’s Gasplasma plant in Swindon
ting in place stable and transparent mechanisms to incentivise investment in the most efficient and clean technologies to allow them to come to the fore thereby reducing their cost of deployment once established. In summary, the waste to energy sector is entering a period of unprecedented expansion. ACTs that can deliver high electrical efficiencies with minimal environmental impact and on a large scale have become deployable. At the same time, a growing realisation of the effects that both waste and fossil fuels can have on the planet has led governments to push for greener, cleaner solutions. We have in place both a clear understanding of the need to manage our waste and energy and the technologies that make this possible. With the correct level of support from governments and local authorities, these applications for clean, safe energy from waste will set new and better standards. e:
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July/August 2012 | Renewable Energy Focus
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