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April, 2012:

Carbon capture ‘viable with long-term support’

18 April 2012 Last updated at 23:12 GMT

Gas-fired power station

The government’s new CCS competition allows entries relating to gas as well as coal generation

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Capturing and burying the greenhouse gas carbon dioxide from power stations is viable – but long-term government support will be needed, a report says.

Specialists in technology and economics spent two years researching the issue for the UK Energy Research Council.

The government recently announced a £1bn fund to help carbon capture and storage (CCS) develop; but the report says wider support is needed.

CCS is widely seen as an important part of a low-carbon electricity system.

“CCS is seen as the key to many scenarios of how to mitigate climate change, whether that’s the UK meeting its targets on cutting emissions or global targets that keep warming below 2C,” said the report’s lead author Dr Jim Watson, director of the energy research group at Sussex University.

“But unlike other low-carbon technologies, CCS doesn’t exist at the commercial scale. We don’t know when they will be technically proven at full scale, and whether costs will be competitive with other low-carbon options.

“So it is vital that the government’s commitment leads to several full-scale CCS projects as soon as possible; only through such learning by doing will we know whether it is a serious option for the future.”

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Levels of interest from business are phenomenal, despite the years of prevarication”

End Quote Matthew Spencer Green Alliance

Other countries including Germany, Norway, the Netherlands, the US and China are also exploring the technology.

The government opened its first competition for CCS funds in 2007, but abandoned it four years later when the last contender – the Longannet coal-fired power station near Edinburgh – withdrew, saying the economics did not work out.

The new government scheme is far more flexible over what types of technology are eligible for funding, which the report says is the right approach.

Equally, it says, the single £1bn fund will not be enough to take the industry from its current fledgling state to the government’s target of having 10GW of UK generation capacity equipped with CCS by 2030.

Leadership chance

Equipping coal- and gas-fired plant with CCS makes them considerably more expensive to run.

The plant itself becomes less efficient, meaning more fuel has to be burned to produce the same amount of electricity.

CCS-fitted stations could form part of a low-carbon mix alongside nuclear and renewables

The CO2 must be transported to its resting place – probably in liquid form through a pipeline – and a disposal site must be properly explored beforehand and monitored afterwards to make sure nothing escapes.

The report says the economic incentives for this extra investment will have to come from reforms to the electricity market that the government is working out at the moment, designed to supply additional and enduring support through guaranteeing prices for low-carbon electricity.

It also says the UK is well placed to lead the global market in skills and technology, and perhaps even sell some of the copious storage capacity that exists below the UK seabed to other countries.

“The UK has a huge amount of potential storage, amounting to about 700 years worth of emissions,” said another of the report’s authors, Prof Stuart Haszeldine from Edinburgh University.

“But that is as yet unproven; and no commercial company is going to go ahead and build a CCS facility costing maybe £1bn if they don’t know they’ll be able to inject CO2 for 30 years into that site.”

Proving that a site is suitable for CO2 storage needs the same type of exploration needed in oil and gas exploration, he said – and investigating a single site could cost hundreds of thousands of pounds and take five to 10 years, meaning that a programme for doing it should be developed soon.

The government will also have to work out rules on liability for leakage, he said, that are fair to both companies and the public purse.

Matthew Spencer, director of the Green Alliance, which produced its own analysis of CCS recently, agreed that investors needed support and confidence.

“Levels of interest from business are phenomenal, despite the years of prevarication,” he told BBC News.

“We’ve lost a lot of time, and investors have to have much more certainty now if we’re not to lose them; but we do have a good story in the UK of a rapidly growing industry.

“If the government pulls out the stops, we think 10GW is feasible.”

China’s Largest Waste-To-Energy System Heads For Shenzhen

Description: shenzhen

The second phase of the Bao’an Waste-to-Energy Plant, which is invested in by Shenzhen Energy and Environment Company, is expected to be the largest of its kind in China with a daily production capacity of 4,200 tons.

It is learned that Shenzhen produces 12,074 tons of waste are being yielded in Shenzhen every day. Though city has set up seven waste incineration power plants with a total capacity of 4,875 tons per day, it can still not meet the increasing demand.

At present, SEEC incinerates 2,450 tons of waste each day, which accounts for 50% of the city’s total waste incineration. In addition, the company has three projects under construction which are expected to add a daily capacity of 6,300 tons for the city.

Set up in 1997, SEEC is one of the major waste disposal companies in Shenzhen.

Microwave Plasma Gasification Heats Up in the U.S.

Microwave Plasma Gasification Heats Up in the U.S.

Plasma gasification has become a buzzword and the new kid on the waste to energy block. One company has trialled its new process in Mexico, known as microwave plasma gasification, and is starting work on its first commercial facility in Texas. Tom Freyberg investigates claims that the process is 60% more efficient and can produce diesel from waste.

With landfill sites reaching capacity around the world, more and more municipalities are incorporating waste to energy (WtE) technologies into their waste management plans. Political and planning challenges to one side, modern technologies have proven their ability to produce energy or a valuable biogas/synthetic gas (syngas) from waste and divert millions of tonnes from reaching landfill.

Many WtE processes such as mass burn have been in use for decades, but have been refined over the years to their current state today. But it is pyrolysis/gasification currently grabbing the headlines, especially plasma arc gasification.

In short, the latter involves processing organic waste at extreme temperatures (4000ºC – 7000ºC) using an electric arc in a torch to produce a syngas and vitrified slag, a rock-like glassy by-product. Developing across Europe quickly, companies such as UK-headquartered Advanced Plasma Power (APP) has already formed a joint venture to gasify thousands of tonnes of waste unearthed from a landfill mining project in Belgium.

Even across the pond, the North American market is one where companies are also trying to rapidly establish a foothold in the enormous waste market. And it’s clear to see why. Figures from the Environmental Protection Agency (EPA) show that in 2009 Americans generated 219 million tonnes of waste. Of this amount, 74 million tonnes were recycled, resulting in a 33.8% recycling rate. A total of 26 million tonnes were used for energy recovery (11.9%). Interestingly, around 31 million tonnes were sent for thermal processing back in 2000. So, over the period of nine years the amount of waste sent for WtE processing decreased by five million tonnes.

This raises the question of whether plasma gasification could help spearhead a revitalisation of waste to energy across the continent? And developments to date suggest this could be the case.

Plasma gasification progress in the U.S.

To kick this technology off in the region, Geoplasma, part of real estate developer Jacoby Group, has secured a permit from Florida’s Department of Environmental Protection to build the St. Lucie Plasma Gasification Facility in St. Lucie County, worth an investment of $140-150 million. The facility is set to produce 24 MW (gross) of power from nearly 600 tonnes of waste and tyres per day.

Speaking to Waste Management World magazine (WMW), Geoplasma president Hilburn Hillestad says the firm intends to break ground on the project in January 2012, with an 18-month construction period meaning the project will be ready by mid 2013. Technology will be provided by Westinghouse Plasma Corporation, subsidiary of Alter NRG.

Results from Waste2Energy’s pilot plant show 10-20% of energy recovered can power the microwaves

Moving south into Central America, it is new venture Plasma2Energy making headway, using a trial in Mexico as a springboard into the rest of America. The pilot plant in Monterrey, Mexico is processing 10 tonnes of waste per day (3,600 tonnes per year), established in early 2007.

The company is in final negotiations for an agreement with the City of McAllen in Texas, for a 180,000 tonnes per year facility worth $117 million, to process all residential, commercial and green waste generated within the city. It is also set to recover over 1500 tonnes of recyclables over the course of the year. Currently in negotiation with the city municipality, the company says a long-term contract between 20-25 years will be established.

“The first phase of the McAllen project will take 18 months and then another 24 months for phase two, so it will be three and a half years before we start taking waste from the municipality,” Rodolfo Sanchez, CEO of Plasma2Energy™ tells WMW. “The city produces 450 tonnes of waste per day and after separation and moisture content we will need to gasify around nearly 300 tonnes of waste per day and generate 27 MW of electricity net to the grid.”

Microwave plasma gasification

As the technology distributor, Plasma2Energy uses ABA’s technology, which the company is keen to position as “microwave plasma gasification”. According to the company’s literature: “By harnessing the power of microwave radiation through a patented plasmatron array in the reactor, waste feedstocks and other carbonic materials are heated until they are heavily ionized, forming a cloud of plasma in the material.”

Waste feedstocks and other carbonic materials are heated until they are heavily ionized, forming a cloud of plasma

Heated water vapour is then added to the plasma to create a syngas and inert slag. Produced gas can then be purified and some of it “re-fed” through the reactor, to recover energy and provide enough energy to power the microwaves. In Layman’s Terms, this means the process could be self sufficient.

Plasma2Energy says the microwave technology is where efficiencies can be made. And the question of whether the technology is a giant version of household microwaves used to heat up soup is not as ridiculous as you might think!

“Yes, it is effectively giant microwaves that use heat to ionise the waste,” Sanchez says. “Other processes out there, such as electric plasma arc torch processes, consume almost 80% of the energy they generate. In comparison, the ABA process consumes only 20% of the recovered energy.”

The CEO is keen to stamp out any accusations about company brochures being notorious for self-promotional, exaggerated claims.

“We generate heat by breaking the molecules until they get ionised so we can form the plasma,” he says. “The energy that we use on those microwaves to produce the gas needed is much less than the energy produced from the syngas. Results from our pilot plant in Mexico show that we need 10-20% of energy recovered to power the microwaves.”

The million dollar question to any small start up keen to take on larger, established companies is how does the process differ from the competition? And more importantly, how is this different to plasma arc gasification?

“What we have seen is that with plasma arc and plasma torch processes, you have several torches in the gasifier. They apply the energy to a single point whereas in the case of microwaves, you have a whole area where you’re applying the heat. We actually generate the plasma at the very beginning when the matter enters the microwaves. Energy is applied directly to the matter to form a vortex, helping the heat reach a plasma state and subsequent reaction afterwards.”

Black gold? Plasma rock and diesel

While organic processes are combusted and eventually transformed into a syngas, other materials such as metals, glass and minerals are not gasifiable, but are melted into an inert slag residue. Already established as a recyclable by-product, many waste to energy companies are branding the vitrified recyclate to help with marketing. An example of which is APP’s “Plasmarok”, which it says can be used as a building material or replacement aggregate.

For Sanchez, he says that variations in the feedstock play a big part in the quality, and quantity, of the plasma by-product from the Plasma2Energy process. “In Texas we’re going to have a moulding machine underneath the reactor so we can form bricks,” he says. “It is very light and can take the form of whatever you put it in and cool it. The slag itself is inert and we have a market – construction and the product even has a quality suitable for homes and gardens.

“The most important thing is that the volume of the slag depends on the feedstock. If you separate metals at the beginning, which is what we are planning to do, you have a more efficient process as you don’t have to use the energy to heat the metals. You can recover more energy.”

Plasma2Energy’s proposed $117m facility would process 180,000 tonnes per year of waste in Texas

Another important process by-product in need of discussion; in fact of more significance (and value) than the glassy rock recyclate, is that of the diesel produced. As part of the process, the firm says that clean gas can be processed through a Fischer-Tropsch reaction stage, where part of the synthetic gas condensates into a liquid. This can then be refined to produce biofuels, ethanol as well as ammonium nitrate as a biofertiliser. “The oil that we have collected from the pilot plant comprises 70% diesel,” the CEO quips. “When we are cooling and cleaning the gas, some parts are condensed into synthetic oils. The process can be refined to this set up and whatever you don’t need you put add back to the process for gasification.”

On the topic of how the proposed process will fit in with established recycling efforts in the region, Sanchez says: “We have made the commitment with the City of McAllen that recycling will be priority number one,” says Sanchez. “At households waste is being separated into two different bins – one goes to recycling centres where they separate metals, paper and cardboard. That will continue until we get into the second phase and then we will implement what the city wants to do with the recycling.”

Spreading the word

Moving beyond Texas, the CEO – an engineer by trade – says the patented technological research into plasma gasification took a mighty 17 years to reach market, eventually published by the World Intellectual Property Organization (WIPO) in 2009. Plasma2Energy can now apply for a certificate of patent in the 160 countries that belong to WIPO, with Sanchez admitting his company has an application pending for certification of patent in the United Sates and the European Union.

Plasma is generated at the start when waste enters the microwave

“We have received requests from all over the world and we have a list of project developers identified and ready to specify our technology. We have received several requests from the UK, Italy, Spain, France, Switzerland, Asia, South America and Africa.”

The waste sector, more than others, is known for its slow uptake of new technologies that have yet to be commercially proven. In fact, the expression “the proof of the pudding is in the eating” is frequently cited at conferences discussing new technologies and trials.

Sanchez admits he is facing similar challenges with interested companies requesting data from the Texas facility. Until this facility comes online to produce needed data and the waste agreement with the City of McAllen finalised, Plasma2Energy could find it a challenge to roll out a second full-scale facility.

But, with claims that microwave plasma gasification is 60% more efficient than existing processes, and the ability to produce 70% diesel as a by-product; the ABA process really could be game-changer on the WtE landscape.

Watch this space: microwaves could soon be used for a lot more than heating up your lunchtime soup.

Tom Freyberg is the chief editor of WMW World magazine. email

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What Will It Take To Get Sustained Benefits From Natural Gas?

10 April 2012

By Ramon Alvarez, Ph.D
Environmental Defense Fund blog

Natural gas is reshaping our energy landscape. Though the potential energy security and economic benefits are compelling, the challenge is that natural gas comes with its own set of risks to public health and the environment, including exposure to toxic chemicals and waste products, well construction and design, local and regional air quality and land use and community impacts.

There has also been much confusion about the impacts of increased natural gas use on the climate.  While natural gas burns cleaner than other fossil fuels when combusted, methane leakage from the production and transportation of natural gas has the potential to remove some or all of those benefits,depending on the leakage rate. Methane is the main ingredient in natural gas and a greenhouse gas (GHG) pollutant many times more potent than carbon dioxide (CO2), the principal contributor to man-made climate change.

Proceedings of the National Academy of Sciences (PNAS) Paper

EDF has teamed up with several respected scientists to find a better way to examine the climatic impacts of increased use of natural gas and compare it in place of other fossil fuels in a paper titled “Greater Focus Needed on Methane Leakage from Natural Gas Infrastructure” published yesterday in the Proceedings of the National Academy of Sciences (PNAS).  While methane absorbs more heat energy than CO2, making it a much more potent GHG, it also – luckily – has a shorter duration in the atmosphere.  The combination of these factors makes it difficult to compare methane emissions to other GHGs using conventional methods.

Instead, in the PNAS paper, we propose the use of an enhanced scientific method: Technology Warming Potentials (TWPs).  Specifically, this approach reveals the inherent climatic trade-offs of different policy and investment choices involving electricity and transportation.  It illustrates the importance of accounting for methane leakage across the value chain of natural gas (i.e. production, processing and delivery) when considering fuel-switching scenarios from gasoline, diesel fuel and coal to natural gas.  TWPs allow researchers, policy makers and business leaders to make fuel and technology choices while better accounting for their climate impacts.

PNAS Paper Key Findings

We illustrated the new approach by analyzing commonly discussed policy options.  Using the Environmental Protection Agency’s (EPA) best available estimated leakage rate of 2.1% of gas produced (through long-distance transmission pipelines but excluding local distribution pipelines), generating electricity from natural gas in new combined cycle power plants decreases our contribution to climate change, compared to new coal-fired plants.  This is true as long as methane leakage rates stay under 3.2%.

Natural gas powered cars, in contrast, do not reduce climate impacts unless leakage rates are reduced to 1.6% (compared to our estimate of current “well-to-wheels” leakage of 3.0%).  In heavy trucks, the reduction would need to be even more pronounced—converting a fleet of heavy duty trucks to natural gas damages the climate unless leakage is reduced below 1.0%.

The PNAS paper only provides illustrative calculations with EPA’s current estimate of the methane leakage rate and better data is needed to more accurately determine leak rates.  Measuring how much gas is lost to the atmosphere and where the leaks are occurring will help to further target leak reduction opportunities to ensure that natural gas will help mitigate climate change.  EDF is working to obtain extensive empirical data on methane released to the atmosphere across the natural gas supply chain, since the climatic bottom line of fuel switching scenarios involving natural gas is very sensitive to this parameter.

Not only is the data on methane leakage far from definitive, but climate impacts from leakage – and other key public health and environmental risks – could be reduced by strong standards and improved industry practices.  There are many practices and technologies already being used in states such as Colorado and Wyoming, and elsewhere by natural gas companies to reduce gas losses, which results in greater recovery and sale of natural gas, and thus increased economic gains. The return on the initial investment for many of these practices is sometimes as short as a few months and almost always less than two years.  In these tough economic times, it would seem wise to eliminate waste, save money and reduce environmental impact.

In sum, the paper’s results suggest that methane leakage rates matter: they can materially affect the relative climate impacts of natural gas over coal and oil.  While the paper does not draw hard and fast conclusions about the future implications of fuel switching, it does provide guidance in terms of the leak rates necessary for fuel switching to produce climate benefits at all points in time.

EDF Methane Leakage Model

We also released a new methane leakage model, based on the science described in the PNAS paper, which allows anyone to test a range of scenarios to quantify the climate benefits, or damages, of natural gas production and usage given specific methane leakage rates.  Users can vary the key system attributes independently to see how they affect net radiative forcing (the primary index used to quantify the effect of greenhouse gases [GHGs] on global temperatures) from U.S. emissions over time.  Visit to plug in different variables and observe the outcome.

For more information, visit

This entry was posted in Methane leakage, Natural Gas.


What a waste

U.S. Plasma Gasification Firm Secures Investment

Oregon based InEnTec, a developer of a plasma gasification technology to convert wastes into fuels and other products, has secured a strategic investment from Lakeside Energy…Read More

ETI Seeks Proposals for ‘First of Kind’ Gasification Demonstrator

The UK’s Energy Technologies Institute is seeking partners for a new £13 million project to design and build a ‘next generation’ demonstration facility for waste gasification technology…Read More

Access to Plastics Recycling Rises to 95% in Canada

The Canadian Plastics Industry Association has published updated figures that show over 95% of Canadians now have access to plastic recycling options…Read More

Contract to Build 350,000 TPA Waste to Energy Facility in Cardiff

Construction work on Wales’ first CHP waste to energy facility is due to start following a deal between Viridor, engineers CNIM and construction firm Lagan

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• Apple to Build 5 MW Biogas Fuel Cell at Maiden Data Center
• Joint Venture to Develop 68 MW Multifuel Facility in Yorkshire
• Poor Gas Collection & Landfill Fires Cost California Operator $3.8 million
• Waste to Energy Technology Review by Western Australia’s EPA
• Contract Extension for Kerbside Recycling in Edinburgh
• Contenur Wins Side Loading Bin Contract in UAE
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• Court of Appeal Odour Ruling Smells Costly for Waste Industry

Green Groups Sue EPA over Coal Ash Rules

5 April 2012

Reuters) – A coalition of environmental groups filed a lawsuit on Thursday to force the Obama administration to finalize new rules regulating the containment and disposal of coal ash, a power plant byproduct activists say threatens public health.

Earthjustice, the Sierra Club, the Environmental Integrity Project, and several other groups want the Environmental Protection Agency to finalize coal ash standards the agency proposed after a massive and expensive 2008 spill.

“It is well past time the EPA acts on promises made years ago to protect the nation from coal ash contamination and life-threatening coal ash ponds,” Earthjustice attorney Lisa Evans said in a statement. The groups filed suit in the U.S. District Court for the District of Columbia.

The EPA proposed regulating coal ash, or byproducts of coal combustion in power plants, in 2010, after a spill at a storage site at a Tennessee Valley Authority power plant.

The 2008 accident caused a flood of sludge for which cleanup was estimated to cost more than $1 billion.

Environmental groups way coal ash disposal can lead to groundwater contamination from improperly built storage ponds and landfills. The EPA has said contaminants such as mercury, arsenic and cadmium in coal ash could causecancer if they get into the water supply.

Earthjustice last week released data obtained from the EPA that shows previously unknown instances of contaminated groundwater at 29 U.S. power plants. The report shows arsenic, lead and other pollutants in water near the coal-fired plants.

“When plants are monitoring they’re generally, much more often than not, finding the contamination,” Evans said. “Which then, of course, begs the question of, why aren’t there federal protections to stop this contamination?”

The EPA did not respond to requests for comment.

The Obama administration is going into a tough election year fighting accusations that its regulations will stifle business in a struggling economy. Republicans in Congress have attacked the EPA in particular, accusing it of a war on coal-fired power plants due to new emissions rules.

The agency proposed two versions of the coal ash rules. One would be tougher on existing facilities; both versions would require liners and groundwater monitoring at new storage sites.

The final rules are expected sometime this summer, but Evans said the EPA needs to set a hard deadline to finish.

Lawmakers from both parties have criticized the proposed changes. Some say regulating coal ash would stifle industries that use recycled waste. In a letter to EPA Administrator Lisa Jackson in 2010, 35 senators argued the proposal would place unfair burdens on utilities and could cost jobs.

The U.S. House of Representatives passed a bill in October that would hand the responsibility for regulating coal ash disposal to the states. A bipartisan group of senators backed the bill, but it has not gained much attention since.

(Reporting By Emily Stephenson; Editing by David Gregorio

Waste to Energy Technology Review by Western Australia’s EPA

Waste to Energy Technology Review by Western Australia's EPA

A comprehensive review of the way waste to energy facilities operate around the world is to provide Western Australia’s State Government with the most up-to date information on waste to energy technologies.

According to Environment Minister, Bill Marmion, the review has already officially started, and is being conducted by the Environmental Protection Authority (EPA) and the Waste Authority.

The purpose of the review is to examine different technologies used in Europe, the USA, Japan and Australia.

“This is a comprehensive study that will provide the State Government with the most up-to-date information on the environmental performance of waste to energy facilities,” explained Marmion.

“The study will look at a range of operating facilities around the world using a variety of technologies including gasification and incineration and examine the way these facilities are designed, how they operate, their emissions and the regulatory framework under which they operate.”

The Minister said that with a number of proposed waste to energy facilities currently being assessed by the EPA, the information would prove essential.

Marmion added the review would focus on the processing of mixed non-hazardous waste – including municipal refuse and commercial waste – and low level hazardous waste such as tyres, paints and common solvents.

It would not be considering high level hazardous waste or hospital waste.

The Minister said that waste to energy facilities were an important way of ensuring waste was used for a social and economic purpose rather than being dumped in landfill.

Advice from review is expected to be published by Western Australia’s EPA by end of year.

Read More

University Studies Mixed Feedstock Waste to Energy in Australia
A feasibility study into the use of a mixture of waste streams in the City of Greater Bendigo, in the state of Victoria, Australia is to examine the business case for the introduction of Australia’s first multiple stream waste to energy facility.

Australian Biowaste Pyrolysis Developer Makes Public Offering
Pacific Pyrolysis is seeking to raise between $2.2 million and $4 million from an initial public offering and then list on the Australian Securities Exchange, according to a report in The Australia.

Putting discarded waste to use by creating energy – E & T Magazine

vol 7, issue 3

Putting discarded waste to use by creating energy

26 March 2012

By Sean Davies


Landfill site

EFW plant

Energy from waste projects, while appealing for a variety of reasons, have struggled to gain acceptance. But a new scalable method could provide the perfect solution.

Last year almost 300 million tonnes of waste were created in the UK, and almost half of that ended up in landfill. With government regulations aiming to reduce the amount of waste sent to landfill to zero by the end of the decade, the major challenge facing society is just what to do with it all.

One option is to burn it in waste incinerators, but that carries its own environmental challenges. Another, more appealing option is to use the waste as a fuel to generate electricity or heat using Energy from Waste (EFW) technology. This would, on the face of it, appear to be a win-win scenario; disposing of waste as well as helping the UK reach its target of 15 per cent of energy from renewables by 2020, as laid out in the EU renewable Energy Directive.

While all new EFW plants must meet strict emissions standards, including those on nitrogen oxides, sulphur dioxide, heavy metals and dioxins, that does not stop them facing objections from the environmental lobby. Concerns include fine particulate, heavy metals, trace dioxin and acid gas emissions, even though these emissions are relatively low from modern incinerators. Other concerns include toxic fly ash and incinerator bottom ash management.

The traditional method of using incineration to convert municipal solid waste to energy is a relatively old technology. Incineration generally entails burning waste to boil water, which powers steam generators that make energy to be used in our homes and businesses.

However, that is far from the only option and a host of projects around the globe are pushing the boundaries of EFW technologies. There are a number of other new and emerging technologies that are able to produce energy from waste and other fuels without direct combustion; these include gasification, plasma-arc gasification, pyrolysis and, for a non-thermal option, anaerobic digestion.

One option that is particularly appealing is pyrolysis. It can best be described as the thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible. Pyrolysis of organic substances produces gas and liquid products and leaves a solid residue richer in carbon content.

In pyrolysis, the heating occurs in the absence of oxygen and the released gases are gathered and stored for later use. One company that is developing an EFW system is Farnborough-based Qinetiq. In its system, a large screw-shaped column takes in up to 100kg per hour of untreated mixed waste including glass and tin, and particularly troublesome waste sources for thermal waste approaches. The waste is heated, releasing gases that are removed and used for heat or to power a steam turbine. What exits the system is a glassy substance just 5 per cent the volume of the waste that entered, and 400kW of power.

One of the chief drawbacks of commercial-scale EFW plants is the volume of waste they require. While this would appear to be an advantage, it has the drawback of fleets of lorries driving around the country delivering waste with all the attached environmental and social concerns.

The solution would appear to be smaller, localised EFW facilities, but to date that has proved to be an elusive concept. However, thanks to a solution initially developed for the Royal Navy by Qinetiq that may soon become a reality.

“We understand waste management challenges and we believe that the market is ready for small scale energy from waste solutions,” says John Ryley, managing director of the Technology Solutions Group at Qinetiq. “After eight years of thorough research and delivery, we have built on our waste disposal systems that are currently in service with the Royal Navy to develop the next generation EFW solution.”

The genesis for this technology was born out of a terrorist attack that took place 12 years ago. When the USS Cole entered the Yemeni Port of Aden in October 2000, its dual purpose was to take on fuel and offload several tonnes of rubbish accumulated during its tour of duty. That call into port had tragic consequences when a suicide bomb attack from a small boat left 17 dead and 39 injured.

Waste on naval vessels was becoming such a problem that during the Gulf War it was common to see a Royal Naval frigate towing a barge full of waste that could not be dumped at sea. “The MoD then came up with a requirement to have energy from waste plants deployed on the large ships,” Ryley explains. “This was then deployed eight years ago on HMS Ocean and it allows it to remain on station a lot longer.

“We did an analysis of the technologies available and came to the conclusion that pyrolysis was the cleanest, the most effective and offered the best reliability as well as being the most cost effective to construct and operate.”

The story so far

From those naval origins Qinetiq has refined the process and now has a plant installed at its Farnborough facility, which in the near future will be able to provide heat for use at the site. It will consume around 2,000t of mixed waste each year, enough to generate enough heat for about 300 homes or electricity for 50.

The most efficient way to use such a plant is to make use of the direct heat output, but it can also be coupled with a steam generator to produce electricity.

“We have been talking to some major supermarkets and they would look to take 20-30 units for their distribution centres,” Ryley adds. “The large supermarkets take food in and waste back: so when the waste arrives back at the distribution centre, instead of going to landfill it can go through the plant.

By mid-summer they expect to have any reliability concerns ironed out and a bill of materials standardised that will allow the plant to go into production – something that the company plan to outsource. For the test customers, Qinetiq is looking to select one site each from three key major sectors – health, retail and facilities management sector. “We are looking for an early adopter,” he continues. “We need a company that has a desire or requirement to adopt early technologies. Some supermarkets want proven technology so they are at the end of our chasm. Some say, ‘yes, this is a great idea, I want it tomorrow’. We tend to talk to a lot of hospitals who want this tomorrow.”

A model for waste

One big advantage of the EFW system is that there is no sorting of waste streams and no pre-heating required, the only proviso being that the moisture content cannot be too high as that would greatly reduce the efficiency of the plant. It can take mixed plastic, gas and metal. “We are working with Rushmore Council and they are delivering all of their mixed plastic waste and glass waste to us and we are running that through the plant.”

When it comes to optimising the performance of the plant in the future, Ryley admits that they may look at exactly what the optimum fuel would be, but at present they are content to let it run on mixed waste. What they have developed is a simulation tool that allows prospective clients to judge the viability of the system.

“We go to clients with the tool and ask them to input their current landfill and transportation costs, along with monthly waste estimates, and the mix of their waste types. Armed with this information, and their current power and heating spend, we are able to deliver a revenue model. On a simple chart they can see their return on investment allowing the client to see an estimated cost against value for the product.”

As an example Qinetiq pays about ‘90,000 a year to get rid of its waste from the Farnborough site. “From this point forward, that money is going to be channelled into the plant operation, so that will be a saving straight away,” Ryley says. “They will also not be buying as much heat.”

Financial solutions

Ryley suggests that the drivers for adoption of EFW are multiple, but they are primarily a combination of legislation, cost-cutting and the desire to be viewed as an environmental leader. The financial argument is solid. If you funded the purchase of the plant the return on investment would be between three and five years, well inside the usual investment criteria.

But the model that Qinetiq is adopting offers an even more advantageous financial solution. The plan is to lease the plant, and Ryley claims that the monthly payment is often less than the combined cost of fuel and waste removal. “If they are spending £100,000 a month on electricity or heat and this plant goes in on a lease costing, for example, so many thousands a month, it is less than they are paying and there is an immediate saving.”

Aside from making prudent financial sense and ticking the environmental box, there is also the matter of job creation. “For every one of these plants, you need two people to run it per shift. We have done some market research and the market around the UK for this type of product is about £4bn.

“With any new technology that is coming onto a market you need a service infrastructure round it. Whether it’s local or whether it’s remote, so you probably need some regional engineers and some local engineers as well just to monitor it.” Remote monitoring is made available by a multitude of Allen Bradley sensors that can be monitored locally or remotely.

Commercialising MOD IP

Often, for companies working in research and development in the military arena, the commercialisation of IP can be fraught with problems, but in this instance there were no such hoops to jump through. The majority of the IP was owned by Qinetiq, although the company had to acquire some additional IP for the plant. The agreement with the MoD on this project was that they could exploit the technology that they developed and that led to this plant – dubbed EFW7000. But even though this has yet to enter the commercial landscape there are plans afoot to develop even smaller versions, eventually down to single household size, although that would carry a whole new raft of challenges.

The target is 2016 for the mini EFW, but before that happens there need to be further breakthroughs. One of the key challenges is temperature; on the EFW7000 the only use of external power is to get the process up to working temperature, in excess of 700’C, after that it fuels itself.

However, in a household appliance it would almost certainly be fed waste on an intermittent nature, meaning that more external fuel would be required to achieve a working temperature.

“It would need a stand-by mode and you would have to work the plant in such a way that it integrated with the house, so when you put the waste in it holds it for a certain time,” Ryley admits. “It would then fire again and get rid of the waste and produces heat or electricity and if there is too much heat or too much electricity it goes back into the grid.”

But that’s for the future. For now the systems start appearing around the UK this year, to the benefit of the war on waste and the fight to comply with renewables obligations