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The role of waste-to-energy in the circular economy

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CLP Power to tap methane from Tuen Mun landfill for electricity

The company is awaiting an environmental approval for its plan to build generators on the site; project will cost “more than HK$100 million”

http://www.scmp.com/news/hong-kong/health-environment/article/2065471/clp-power-tap-methane-tuen-mun-landfill

The larger of the city’s two electricity providers will seek approval for the installation of 14-megawatt electricity generating units powered by gas at a Tuen Mun landfill to expand its portfolio of “renewable” energy projects.

CLP Power managing director Paul Poon Wai-yin said the large amounts of flammable gases such as methane, produced from the decomposition of municipal waste, could be tapped for power.

About 7,300 tonnes of such waste is dumped in the landfill at the tip of Nim Wan daily.

Poon said the waste-to-energy conversion was a better source of renewable energy than solar or wind, which required massive amounts of land and investment, adding:

“On one hand it will help reduce [greenhouse gas] ¬emissions from landfills, and on the other, help replace the burning of fossil fuels to generate electricity.”

Quince Chong Wai-yan, head of corporate development, said the new facility – estimated to cost “more than HK$100 million” – would have a minimal impact on tariffs due to its limited scale.

The project’s first phase comprises five units capable of generating enough electricity to power 17,000 four-person households for one year. A second phase will add two more units to the site.

A new climate change action plan released by the government last week set new emissions reduction targets for 2030. Authorities hope to achieve this by moving away from coal-fired power generation to natural gas and non-fossil fuels.

While the plan stopped short of a target for renewables, it highlighted a “3 to 4 per cent” capacity, to be realised between now till 2030. Poon said CLP was already on the way to help meet 1 per cent of this mark.

He stressed that the phasing out of CLP’s coal-fired units over the next decade would also be discussed with the government in negotiations for a post-2018 regulatory framework, expected to be completed by the end of the administration’s term.

Greenpeace senior campaigner Frances Yeung Hoi-shan said the facility would help reduce methane emissions, a more potent greenhouse gas than carbon dioxide. But she said most green groups did not consider processed waste a “renewable energy” source. Yeung urged the government to require power companies to incentivise investments in sources such as solar and wind energy in the new regulatory framework.

The new action plan stated that tariffs and renewable energy certificates will be introduced as incentives in negotiations with CLP Power and HK Electric. But Poon did not provide details at a media briefing on Wednesday.

Impact assessments for CLP’s proposed units at the landfill have been completed and the company will apply for an environmental permit shortly. It hopes to begin operations of the first phase in the third quarter next year.

The Environmental Protection Department welcomed the project and said it would facilitate implementation.

Hong Kong government aims to slash carbon emissions with 2030 action plan

While government hopes to reduce total emissions by 26-36 per cent, some critics say the plans lack conviction

Annual carbon emissions could be slashed from around six tonnes per person to between 3.3 and 3.8 tonnes by 2030, according to the government’s latest climate change action plan.

But a think tank and green group believe the plan lacks hard targets for renewables and the ambition to phase out coal in the fuel mix.

The target, which will translate to an absolute carbon emission reduction of 26 to 36 per cent and reduction of 65 to 70 per cent in carbon emissions per GDP from 2005, will use a cleaner, less coal-intensive fuel mix and more energy efficient buildings and transport.

Renewable energy would also be applied on a “wider and larger scale”, it said.

Measures to incentivise private investment in renewables could be introduced in the post-2018 regulatory framework with power companies, which is being negotiated, the plan says.

Government departments are looking at installing floating photovoltaic systems on reservoirs, with two expected to be completed at Shek Pik and Plover Cove this year, and on slopes, such as at the old Anderson Quarry.

The Environment Bureau however stressed that the city did not have favourable conditions for large-scale commercial use and as such, did not set any concrete targets for 2030.

Also missing were hard targets for reducing energy use in the private buildings sector. Secretary for the Environment Wong Kam-sing said a consensus had been reached for the building sector to voluntarily reduce electricity consumption on an “ongoing” basis, with details still to be finalised.

“Overall we would like to make it a kind of pattern similar to the Paris agreement,” he said, referring to the land climate accord, which requires each individual country to work toward its own nationally-determined contributions to curb global warming and report back every five years.

Maura Wong, CEO of think tank Civic Exchange believed the plan lacked commitment. “We still don’t know by 2030 whether we will be coal-free and what the mix will be between natural gas and nuclear,” she said. “They need to be ambitious enough to set a clear date of when they will completely phase out coal.”

WWF-Hong Kong’s conservation director Gavin Edwards said: “We welcome the government’s openness to 3 to 4 per cent renewable energy, but believe that it should be a formal target and … more ambitious with at least 5 per cent renewables by 2030.
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Source URL: http://www.scmp.com/news/hong-kong/health-environment/article/2064045/hong-kong-government-aims-slash-carbon-emissions

Big Oil Moves In With New Administration

Deal-making used to be done in smoke-filled rooms. Now it will be done in a cabinet room filled with the smell of big oil.

http://www.courant.com/opinion/op-ed/hc-op-thorson-big-oil-in-white-house-0119-20170118-column.html

The parallels between the war on tobacco half a century ago and the current war on fossil fuel consumption are astonishingly close.

During the 1960s, my brief flirtation with smoking was typical teenage behavior. The adults we modeled ourselves after were seldom seen without something burning in their hands. Little did I know then that the tobacco companies were actively promoting a habit they knew to be dangerous, and were fraudulently hiding the truth about medical and societal costs. Eventually they were identified, tried, convicted and punished.

Something eerily similar appears to be taking place with petroleum. Last week, the attorneys general of Massachusetts and New York won a ruling against Exxon Mobil Corp. Suffolk County Judge Heidi Brieger ruled that the company must release 40 years worth of internal records related to climate change as part of a fraud investigation. On that very day, Exxon Mobil’s CEO, Rex Tillerson, was refusing to answer questions about climate change being put to him by the U.S. Senate, which was grilling him as President-elect Donald Trump’s nominee for secretary of state. As with the tobacco trials of yore, state attorneys general are investigating a deliberate cover-up, and the target corporation is responding with aggressive countersuits.

This is actually very old news. Seven years ago, Erik Conway and Naomi Oreskes highlighted the historic parallels between big tobacco and big oil in their powerful book “Merchants of Doubt.” The alleged common thread between these industries is the use of corporate power to actively promulgate disinformation. Another common thread is the claim by both that they’re merely meeting a market demand, rather than creating one.

Though the oil companies did not push us into oil addiction the way the tobacco companies did, they were certainly complicit in the process. Within a half-century, American culture was hopelessly addicted to petroleum for space heating, electrical generation, military applications and most important, the personal automobile. Car culture gradually became part of our national infrastructure in the form of personal garages, interstate highways, vast suburbs, multi-lane bridges, drive-in movies, shopping malls, urban parking garages, drive-through fast food restaurants and many others.

Winning the war on tobacco required that lawsuits name individual corporations as defendants. This is beginning to be the case for carbon-polluters, according to Carroll Muffett, president of the Center for International Environmental Law in Washington, D.C. His recent article in the “Bulletin of Atomic Scientists” credits the work of Richard Heede, which now allows us to identify “a discrete class of defendants.”

Heede is an independent “carbon accountant” whose office is a rented houseboat in Sausalito, Calif., in San Francisco Bay. His accounting is a remarkable, unprecedented story of dogged perseverance and number crunching that’s detailed in the Aug. 25, 2016, “Science.” It covers Heede’s 2013 report that nearly two-thirds of our cumulative global carbon emissions came from just 90 companies, eight of which are responsible for 20 percent of the total.

Third on that list of global polluters is Exxon Mobil. Fifth is Russia’s state-controlled Gazprom. It’s no wonder that Rex Tillerson and Vladimir Putin are close comrades. For all practical purposes, they are in the process of becoming co-defendants in the largest class action suit ever: a case of 7 billion world citizens vs. 20 powerful companies.

The direct link between petroleum and political power has never been more clear to me. The source of that power is an addiction to fossil fuels that’s been promulgated by the energy companies and the states that support them.

Under the Obama administration we made great progress kicking the fossil fuel habit. This trend must continue, not because climate change is bad in and of itself, but because the human-created disruptions are already wreaking havoc.

With tobacco, the harm was breathed inward to our lungs. With fossil fuels, the harm is being breathed outward into Earth’s lung, our atmosphere.

Robert M. Thorson is a professor at the University of Connecticut’s College of Liberal Arts and Sciences. His column appears every other Thursday. He can be reached at profthorson@yahoo.com.

How China has embraced renewable energy and Hong Kong hasn’t, and what’s behind city’s green power inertia

Summer 2016 saw record heat, and health problems from air pollution are rising, yet green energy projects have been shelved or denied funding; electricity firms lack incentives to go green, WWF says

Professor Johnny Chan Chun-leung is one of Hong Kong’s most eminent climate and energy scientists, and he is a very frustrated man. This month Beijing announced it would invest 2.5 trillion yuan (HK$2.8 trillion) in renewable energy technology by 2020 to establish the nation as world leader in sustainable and clean energy, and create 13 million jobs. Meanwhile, Chan and other respected scientists in Hong Kong are struggling to obtain financial support for their green energy projects.

Whereas China embraces wind, tide, solar and wave energy as essential tools to tackle climate change and its acute air pollution, attitudes in Hong Kong appear as fossilised as the fuel that provides 78 per cent of its energy needs.

Chan, chair professor of atmospheric science at the City University of Hong Kong’s School of Energy and Environment, outlined details of an innovative tidal turbine project at a conference on renewable energy last week, organised by the city’s Business Environment Council. Chan’s team has developed a system that can generate electricity even in low tidal streams, typical of the seas around Hong Kong. Though it is early days, trials staged at the Gold Coast Marina in the city’s Tuen Mun district produced encouraging results.

He now needs funding to scale it up, with a view to offering the city a viable green energy alternative, but his application to the Environment and Conservation Fund for HK$2 million was rejected. “The ECF told me today that I ‘did not demonstrate the merits and contributions of the proposed study to environmental protection’,” he says. “How ridiculous.”

It is not an isolated incident. Others complain privately that Hong Kong funding bodies are “overly risk averse” and are rarely enthusiastic about funding green energy research and development.

“I believe more can be done to promote local funding for R&D for all renewable energy components,” says Dr Walid Daoud, a solar energy expert from City University and another speaker at the council’s conference. Many believe these difficulties are just one symptom of a wider malaise when it comes to supporting green energy in Hong Kong.

“Hong Kong performs badly in overall carbon emissions and renewable energy,” says Cheung Chi-wah, senior head of climate and footprint programmes at environmental campaign group WWF-Hong Kong. He notes that the city’s emissions of greenhouse gases responsible for global warming have been rising steadily and are 23 per cent above their level in 2002. That was the same year the Hong Kong government published its first study of renewable energy, compiled by the Electrical and Mechanical Services Department. The report estimated that 17 per cent of Hong Kong’s energy needs could be supplied by solar power alone.

It also made a key primary recommendation that the government should set targets for renewable energy’s contribution to demand of 1 per cent, 2 per cent and 3 per cent for 2012, 2017 and 2022, respectively. Nearly 15 years later, with electricity consumption rising about 5 per cent a year, the city recording record-breaking temperatures last summer, and health problems due to worsening air pollution growing, very little has been achieved. Instead of the proposed 2 per cent target for 2017, the latest data shows that the proportion of energy used in the city that is produced by renewable means is still less than 1 per cent – far from the 17 per cent potential – and the targets have not even been implemented.

Indeed, by 2012 only 2.2 megawatts of solar photovoltaic panels, capable of meeting 0.01 per cent of Hong Kong’s energy needs, had been installed.

Hong Kong is also one of the few advanced cities in the world with no feed-in tariff scheme, or “net metering system”, in place. This means that, rather than small-scale green energy producers being paid for contributing any excess energy to the grid, they can only donate it.

Energy consultant Mike Thomas, of the Lantau Group, another speaker at the council’s event, thinks it is unhelpful to compare China and Hong Kong in terms of being “behind or ahead” because of the vast differences in the two economies’ scale, resources and political systems. He also believes Hong Kong is taking the right steps by implementing the government’s new fuel mix for energy supply by 2020, which consists of about 50 per cent natural gas, around 25 per cent nuclear power and more use of renewable energy sources. Natural gas is still a fossil fuel, but 30 per cent to 50 per cent cleaner than coal in terms of emissions.

“It is true that there is very little renewable energy, strictly speaking, but given the rabid debate about the use of green space for housing, I’m not sure that converting the hillsides to solar panels would appeal either,” he says. The issue of “low energy density” (the relatively high land area needed to produce 1 kilowatt of renewable electricity) is often cited by opponents of renewable energy in Hong Kong, which, including its 263 islands, has a land area of just 1,104 sq km.

Douad calculates the city would need to cover 20 per cent of its surface area with 10 per cent efficient solar panels to meet its energy needs, yet he remains a firm advocate of solar power.

“The 20 per cent is for the actual lateral 2D land use. However, we could also consider the vertical 3D of the urban landscape, using building walls as well as rooftops, sun-exposed roads and highways, sound barriers and water reservoirs,” he says.

While delegates at the council’s conference earnestly discuss the possibilities of using renewable energy locally, most leading cities have already embraced renewables and the smart grid – the use of digital technology to improve reliability, resiliency, flexibility, and efficiency – and have coherent policies in place to foster them.

Singapore is ramping up the use of solar panels through initiatives such as SolarNova, a government-led programme, and investing in green energy research via The Energy Research Institute. The city state is already seeing positive results. Figures for 2014 show that green energy sources contributed 3.7 per cent of total energy consumption (up from 2.4 per cent in 2005) and analysts expect that figure to top 5 per cent by 2020.

Hong Kong does have small-scale solar schemes designed for local consumption, and some government buildings generate solar power, but its approach to solar energy is piecemeal.

CLP Power, one of the city’s two electricity suppliers, commissioned its award-winning renewable energy power plant on Town Island in Sai Kung in January 2010, comprising wind turbines and solar panels, to supply the needs of the island’s drug rehabilitation centre, and says it has connected about 250 small-scale local schemes.

The other supplier, Hongkong Electric, says about 70 local use renewable systems have been connected to its grid over the past 10 years. It also operates a 1MW solar plant and the only wind turbine connected to Hong Kong’s power grid.

It might be imagined that geographical restrictions and a scarcity of available land would make harnessing offshore wind, wave and tidal power – as Chan proposes – more attractive, but there is little sign of progress on any of these. Detailed proposals from the electricity companies to build offshore wind farms were awarded environmental permits, but both schemes were shelved in 2013 and mysteriously disappeared from the local energy agenda.

“We are in the process of collecting wind, wave and other environmental data, along with a review of the engineering design, to complete the feasibility study,” a CLP spokesman says of its plan.

Hongkong Electric’s proposed wind farm in waters off Lamma Island was to supply 1.5 per cent of its total output. Asked about the proposal, a company spokesman says “field wind measurement has been going on since 2012”.

Cheung says no one in the industry understands why the company needs to collect five years of wind data. He suspects the real reason for offshore wind power being dropped is that the schemes of control both power companies have negotiated with the government, which regulate their profits on operations and investment, do not offer enough financial sweeteners for either company to proceed.

The current schemes of control are due to expire by end of 2018, and the government is negotiating terms with the companies to renew them. Cheung thinks it’s “a perfect time for the government to show its determination by introducing significant targets and incentives for energy consumption reduction and [renewable energy] development”.

One of the thorny issues that will need to be ironed out is tariffs. Hong Kong has some of the cheapest and most reliable power in the world (electricity costs about half what it does in New York). Although it is widely believed that greater use of green energy is essential, there is less agreement on who will pay for the higher prices or pick up the bill for integration of an intermittent power source to the grid.

While energy costs account for only 1.6 per cent of the average Hong Kong household’s budget, there is little commercial incentive for change and little political appetite for heaping extra costs on hard-pressed families.

There is more hope than expectation that Chief Executive Leung Chun-ying will use his final policy address to announce Hong Kong will follow Beijing’s lead and reveal a bold new policy for renewable energy with defined targets, a credible strategy to achieve them, and support for home-grown innovations such as Chan’s.
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Source URL: http://www.scmp.com/lifestyle/article/2062467/how-china-has-embraced-renewable-energy-and-hong-kong-hasnt-and-whats

Costa Rica Ran Almost Entirely on Renewable Energy in 2016

http://readersupportednews.org/news-section2/318-66/41162-costa-rica-ran-almost-entirely-on-renewable-energy-in-2016

Costa Rica ended 2016 on a particularly green note.

The Central American nation ran entirely on renewable energy for more than 250 days last year, the country’s power operator announced.

Renewables supplied about 98.1 percent of Costa Rica’s electricity for the year, the Costa Rican Electricity Institute (ICE) said in mid-December. Fossil fuels provided the remaining 1.9 percent.

The country of 4.9 million people gets most of its electricity from large hydropower facilities, which are fed by multiple rivers and heavy seasonal rains.

Geothermal plants and wind turbines are also prominent sources of power, while biomass and solar power provide a tiny but growing share of electricity.

A few diesel-burning power plants round out the electricity mix, but Costa Rica has barely used them in the last two years.

The country enjoyed a 110-day stretch of carbon-free electricity from June 17 through Oct. 6, when the power company briefly turned on its fossil fuel plants. After that blip, Costa Rica resumed its run of consecutive, fossil fuel-free days, a spokesman for ICE told Mashable on Dec. 13.

In 2015, Costa Rica used 98.9 percent renewable energy, slightly more than 2016’s expected total.

Compared to larger, more industrialized countries, Costa Rica seems like a verdant gem amid a pile of black coal rocks.

But Costa Rica’s smaller economy and natural resources give it an advantage over an energy-hungry powerhouse like the United States.

Costa Rica’s population, for instance, is roughly 65 times smaller than the U.S.’s. It also generates about 373 times less electricity than the United States does, according to national energy data from both countries.

Given its huge energy appetite, the U.S. faces a bigger challenge in greening the electric grid.

Nearly 15 percent of the U.S. electricity supply for January-October 2016 came from hydropower, wind, solar and other renewable sources, the U.S. Energy Information Administration reported on Dec. 23.

Coal and natural gas together accounted for nearly two-thirds of U.S. electricity generation over that period. Nuclear power provided the remaining 19 percent.

For Costa Rica, the clean energy success story is likely to continue into 2017.

ICE’s president Carlos Manuel Obregón said the power company expects renewable power generation to stay “stable” this year, thanks in part to the nation’s four new wind farms and favorable hydro-meteorological conditions, which are projected near the nation’s hydropower plants.

The Future of Gas in Decarbonising European Energy Markets

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It’s Official: Solar Energy Cheaper Than Fossil Fuels

http://readersupportednews.org/news-section2/318-66/41073-its-official-solar-energy-cheaper-than-fossil-fuels

enewable energy has reached an important milestone. The World Economic Forum (WEF) has determined that in many parts of the world, solar energy is now the same price or even cheaper than fossil fuels for the first time.

In a handbook released this month, the WEF observed how the price of renewable technologies, particularly solar, has declined to unprecedented lows.

While the average global LCOE [levelized cost of electricity] for coal and natural gas is around $100 per megawatt-hour, the price for solar has plummeted from $600 a decade ago to $300 only five years later, and now close to or below $100 for utility-scale photovoltaic. For wind, the LCOE is around $50.

According to the WEF, more than 30 countries have already reached grid parity—even without subsidies. (“Grid parity” is the point when an alternative energy source, say solar, can generate power at a LCOE that’s equal or even less than the price of traditional grid power.)

“It is relevant to note that the mentioned evolution, market share gain and continued potential for renewable energy do not hinge on a subsidy advantage,” the report added. “In fact, according to [International Energy Agency], fossil-fuel consumption has received $493 billion in subsidies in 2014, more than four times the value of subsidies to renewable energy.”

506-graph-data-energy

The WEF highlighted how the unsubsidized LCOE for utility-scale solar photovoltaic—which was not competitive even five years ago—has declined at a 20 percent compounded annual rate, “making it not only viable but also more attractive than coal in a wide range of countries.”

Countries that have already reached grid parity include Chile, Mexico, Brazil and Australia with many more countries also on the same track. The WEF projects that two thirds of the world will reach grid parity in the next couple of years, and by 2020, solar photovoltaic energy is projected to have a lower LCOE than coal or natural gas-fired generation throughout the world.

“Renewable energy has reached a tipping point,” Michael Drexler, who leads infrastructure and development investing at the WEF, told Quartz. “It is not only a commercially viable option, but an outright compelling investment opportunity with long-term, stable, inflation-protected returns.”

The report follows a recent analysis from the IEA which revealed that total clean power capacity increased by 153 gigawatts, overtaking coal for the first time. To illustrate, about 500,000 solar panels installed were installed around the world every day.

When life gave them air pollution, they made ink

Excited to arrive in Hong Kong, you’re enthusiasm quickly wanes. Your eyes and lungs burn from the smog, as air pollution levels have reached record highs in this cosmopolitan city. The dense haze lingers in the air as children crave to see a rare blue sky.

http://www.freep.com/story/money/business/columnists/josh-linkner/2016/12/16/when-life-gave-them-air-pollution-they-made-ink/95217364/

First looking for fresh ways to market their goods, Hong Kong-based Tiger Beer discovered inspiration from those soot-filled skies. Realizing what a big hazard air pollution had become and connecting with the need to raise awareness to influence new environmental laws and activism, Tiger saw opportunity where others could only focus on the problem.

The big idea? Turn air pollution into ink. A special device to capture pollution was designed and attached to trucks, smokestacks, and cranes, which allowed the team to turn harmful waste into useful art. One hundred and fifty liters of ink have been harnessed so far and transformed into art displayed in the streets of Hong Kong and on the project’s website, Air-ink.com.

“The streets are not only a great place to drink Tiger, they’re also the place where creativity, ideas and passion are born. By using our entrepreneurial spirit to repurpose pollution into ink — the lifeblood of creativity — we’re giving creative people the tools to enhance their streets, and empowering inventors to take small but impactful actions against air pollution,” said Mie-Leng Wong, director of international brands, Tiger Beer, Heineken Asia Pacific, in a company statement.

Tiger Beer tapped into a high visibility social problem and used their marketing might to both make a difference and fuel their brand. This unique marketing approach has generated millions of dollars worth of buzz and customer loyalty, while helping to improve the lives of the 7.2 million residents of Hong Kong. Certainly a much more effective — and impactful — approach than just another TV spot, billboard, or digital ad.

Too often, we look for inspiration in the obvious places. Rarely venturing beyond the four walls of our given fields, its no wonder that we get trapped into the echo chamber of our industries. To seek fresh and inspired approaches, look beyond. Peek up from your to-do list into the wide-open world of possibility. If Tiger Beer can transform pollution into art and enjoy a powerful marketing win as a result, think what you can do when you unleash your own creativity.
There’s opportunity all around us, even in the most unusual places. It’s your job to seize it — right out of thin air.

OPINION: Landfill Could be Best Option for Waste Plastics

Axion Polymers’ Keith Freegard explains why as global temperatures head for potentially catastrophic levels, landfilling rather than burning waste plastics might be better for the environment…

https://waste-management-world.com/a/opinion-landfill-could-be-best-option-for-waste-plastics

Large numbers of energy from waste (EfW) plants exist right across Europe and many of the UK’s municipal solid waste (MSW) and mixed recyclables ‘processing’ facilities are simply exporting a high proportion of mixed material refuse derived fuel (RDF) bales to utilise spare European capacity.

Globally, further waste to energy plants are being planned and built, while landfill is frowned upon as the accepted ‘worst option’ for disposal. Revisiting the decision-making metrics that have led to this ‘accepted waste hierarchy’ might point to a stark choice between the two waste disposal options.

There are valid arguments for the ‘pros’ and ‘cons’ of both waste disposal methods. But what if the true environmental cost of CO2 emissions was also factored into deciding the ‘best option’?

When the full carbon-cost of the disposal method is expressed in ‘pound notes’ – reflecting the impact that large-scale CO2 release has upon the Earth – then this metric could really change decisions about what is ‘good’ waste material to burn as a fuel and what is ‘bad’.

Energy Generation
The non-homogeneous nature of the waste fuels requires robust moving-grate burners to move the combustible materials through the unit. Water-filled side boilers must be used for heat transfer to capture the heat-energy produced.

Even the most modern burner designs are relatively inefficient at energy recovery, generating lower amounts of electrical power per tonne of fuel burned when compared to high-efficiency, combined cycle gas turbine systems (CCGT).

Both power generating units are ultimately doing the same task: converting carbon-rich fuels into electricity (and ideally combined with heat production), while sending atmospheric-polluting carbon emissions up the exhaust stack as a major environmental cost associated with the beneficial electrical power supplied into the local grid.

So what are the solutions? High-efficiency gas turbines are a much more efficient way to generate each kilowatt of power, plus some heat, from fossil fuel sources if measured in terms of the mass of CO2 released per unit of power output.

Waste Fuelled
However, large scale waste-burners consume huge tonnages of waste materials that would otherwise have been landfilled. Siting an EfW plant close to large urban areas can also deliver useful heating into local industry and households.

If the major components in the infeed waste fuel mix to a modern EfW unit are renewable carbon, such as wood, papers, cardboard or organic matters, then the ‘short-life’ carbon atoms released back into the atmosphere via the exhaust stack are ecologically balanced with their earlier carbon-capture in a tree, plant or living organism. So this fraction of the waste ‘fuel’ shows a carbon-neutral effect.

As for the plastic content in residual household or commercial waste, the carbon-rich molecules that create the long-chain polymers (e.g. ethane, propane, styrene, etc.) are derived from crude oil refineries and are then polymerised to make plastics.

Burning these is essentially the same as driving a petrol car or taking a flight – power created at the ‘expense’ of long-life carbon release.

But what if the waste plastic could be separated from the ‘organic or renewable carbon’ wastes and the ‘inert’ carbon-rich, stabilised plastic stored either in the ground or in a covered storage system?

That would represent a long-term carbon-sink and remove those fossil-based materials from the EfW infeed mix. Clearly it would be better to recycle these materials if a technically and economically viable process was available to do that.

The Carbon Balance
Using a CO2 metric alone suggests that it makes more sense to bury large amounts of plastic in a long-term ‘carbon sink’ in the ground and efficiently combust natural gas to satisfy our immediate power needs.

However, until world leaders are prepared to transform the taxation on fossil fuel use in a way that truly reflects the high cost of ‘free carbon release’, then this numeric analysis remains an esoteric academic study.

The Paris Agreement commits countries to taking action to hold temperature rises to well below 2C above pre-industrial levels – and to try to stabilise emissions at a level which would see a temperature rise of no more than 1.5C.

Following the agreement’s signing by the largest CO2 producers and as the COP22 meeting in Marrakesh draws to a close, some world-leading countries may start to introduce the taxation of fossil-fuel carbon release as a means to get the world’s atmosphere back under control and remain within the stated, and agreed, 1.5C global warming limit.

However the major contributors to global carbon emissions, USA and China, appear to remain heavily dependent upon coal-fired power plants and oil-based fuel systems in their economic activity.

Bigger Picture
Eminent scientists worldwide have calculated that a very large proportion of the known (and often privately-owned) reserves of oil, gas and coal already available for extraction and combustion will have to stay in the ground as part of tackling climate change and staying within agreed limits.

The huge shift in corporate and national energy-habits required to leave fossil fuels in the ground will only happen with a Carbon Tax; particularly on the creation of electrical power and directly linked to the tonnes of CO2 released into the atmosphere per unit of fossil carbon consumed.

If that happens, it might be the time to return to that ‘mine’ of carefully stowed thousands of tonnes of good plastic and look at the economics of turning it into new polymer.

With a huge carbon tax slapped on burning it, then the economics would probably work. So these plastics may not have to stay in the ground for too long.

Looking at the bigger picture, we should all be concerned about the wholesale damage of completely uncontrolled burning of fossil fuel. That’s what we’re doing when we’re burning plastic that’s encapsulated amongst the mixed MSW we put in our black bin bags.

Time for a ‘Sky-fill’ Tax?
The short-term political and economic viewpoint is that ‘we’re getting some electrical power from it so it must be a good thing to do’. But this I think reflects the market failure created by very high landfill taxes that are not balanced by an equivalent taxation method to discourage ‘sky-fill’.

It’s a complex and challenging issue that reaches out over the next 20 years; a critical period in our history.

Until we get a carbon tax that puts some seriously big costs on throwing carbon into the atmosphere, I don’t see there being any real change. After all, the Earth doesn’t have a bank account – it’s us humans who operate under that monetary metric.