Waste leads £30bn energy revolution

Below Ross Davidson’s feet, the ground is sinking. But the boss of the Brogborough landfill, on the outskirts of Milton Keynes, isn’t worried that the ankle-deep mud will swallow him up.
It’s a gradual process. Every year, the largest repository of waste in western Europe sinks by about a metre as 25 years of binbag waste putrefies deep underground. Like a tray of tomatoes left out for too long, the 43m tonnes of accumulated muck breaks down into liquid, inorganic solids and methane gas.
Brogborough stopped taking waste a year ago and has since been covered with a thick layer of clay, but it will be decades before the decomposition runs its course. It is up to Davidson to keep the gurgling, seething mess under control. The black, foul-smelling liquid must be siphoned out constantly so that it doesn’t pollute the water table, and underground fires set off by chemical reactions must be smothered. Most importantly, the methane has to keep flowing because Brogborough, though it may not look it, is a gasfield.
More than 550 “wells” have been drilled into the site, their black plastic heads poking out from the mud and willowy grass. Each of them is linked to a central suction system that draws the gas generated by natural decomposition into an adjoining power station. The flow is enough to feed a line of gas-fired engines, two of which originally powered the QE2 across the Atlantic. They generate enough electricity to light 26,000 homes.
It is a set-up that any big power company would dream of. The site is big — 70 metres at its deepest point and covering an area equal to about 250 football pitches. This year it will generate about £18m in revenue for Infinis, the renewable-energy firm, but it costs only about £2m a year to maintain.
It helps that the fuel is free. Using current technology, there is enough gas underground to power the station for another decade at least. For Guy Hands, whose buyout firm Terra Firma owns the business, it’s easy money. Overall, Infinis, Britain’s biggest generator of power from so-called landfill gas, will pocket profits of £55m on £110m in revenue from the 80 sites it oversees around the country.
Yet there is a problem for the landfill business. It is dying. Owing to a combination of rocketing landfill taxes, an increasing aversion to burying garbage in these environment-conscious times, and generous subsidies for new technologies that convert rubbish into energy, Brogborough is the last of its breed.
An entirely new industry of high-tech metabolising plants and digestors is emerging to take its place. These sites are designed, essentially, to do what Brogborough does, but above ground and much quicker and more cleanly. “The great advantage of the new technologies is that instead of waiting for 40 years for this stuff to release its calorific value, we can get it in a week,” said Alan Lovell, head of Infinis.
By 2010, the amount of waste sent to landfill in the UK must be reduced by 25% from 1995 levels under the EU landfill directive. By 2013, it must be cut in half. This is a big challenge: in 2006 the UK sent 65m tonnes of waste to landfill, or more than a tonne per person. AMA Research, a consultancy, estimates that the UK will have to spend up to £30 billion to build the infrastructure to handle what, for decades, has been buried.
“In the past year there has been a sea change in the UK,” said Andy Street, head of SLR, Britain’s largest waste-energy consultancy. “When security of energy supply has become such an issue, it is sensible to get what we can out of waste. Waste isn’t waste. It’s a resource.”
Every year J Sainsbury dumps the equivalent of the Titanic into landfill — about 80,000 tonnes. Most of it, about 70,000 tonnes, is food waste such as ready meals, stale bread and spoilt fruit. By this summer, the supermarket giant expects to be sending no food waste to landfill.
It sounds ambitious, but Lawrence Christiansen, the supermarket giant’s green guru, has a plan. For the past five months Sainsbury has been testing a programme it plans to roll out across the company over the next two years. Instead of sending lorryloads of organic waste from its Northamptonshire distribution centre and 38 surrounding stores to landfill, the company has been trucking it to an anaerobic digestor operated by a small company called Biogen Greenfinch.

The digestor is essentially a large steel stomach. It speeds up the natural breakdown of waste from years to a matter of days by feeding it into an oxygen-starved environment infested with microbes. The process generates a mixture of carbon dioxide and methane, which is burnt to generate heat and electricity. The digestate, the substance that is left, is sold as a type of super-manure for local cereal farms and the heat is piped to a nearby immigrant detention centre.
“This is a win-win-win,” said Christiansen. “It’s green as hell. It saves us a chunk of money, and we can set up that link with the digestate for our suppliers.”
Sainsbury has been so encouraged by the programme that last month it announced plans to build five food-to-energy sites around the country over the next two years. Christiansen expects the digestors to shave an estimated £2m off the company’s annual £9m disposal bill. When they are all up and running, they could be a money maker, with Sainsbury selling surplus power to the grid.
Every year, the food industry produces about 17m tonnes of landfill waste, a quarter of the nation’s total. Because most of it is organic, the opportunity to convert it to fuel is higher than with typical municipal waste, which requires sorting.
Inetec, a small Welsh firm, thinks it has an answer. The company has devised a system that grinds up food and packaging material into a mixture that can be burnt in a converted biomass boiler to generate electricity. Greggs, the baker, Northern Foods and Greencore have all agreed to send their food waste to a new £100m facility that Inetec hopes to build near the docks at Immingham on the Humber. “Instead of woodchips or other biomass, we will be burning food waste. It will be the first plant of its nature almost in the world,” said contracts administrator Gareth Nicholas.
It could be, but at the moment the plant is stuck on the drawing board. Inetec has been struggling for more than a year to find financial backers. As at many companies that are trying to get novel projects off the ground, finding financing from banks that are themselves having financial problems is difficult.
“In the current climate, the banks aren’t lending. They want very safe investments, like schools or hospitals,” said Rob Dustan, environmental business development director at VT Group, best known for its military and shipbuilding work. “When you say you want to build a plant to process waste with a new technology, it’s very hard to persuade them.”
But there are several reasons why companies are beginning to throw their weight behind the shift. For one, being seen as more green than your rivals has become important. Consumers are much more conscious than they were even a year ago about the environmental credentials of the companies they use.
The government is also pushing the issue because reducing the amount of landfill methane — which is 21 times more powerful a greenhouse gas than carbon dioxide — will help it to reach its targets for reducing pollution. The Tories have latched on to waste and recycling as a key issue, proposing a system that would give monthly payments to households that recycle. The government boasts that recycling levels reached 34% this year, up from 8% a decade ago. But that is still well below the European average of more than 50% of total waste.
Britain’s approach is “much less advanced than in most of Europe”, said John Edwards, a partner at the Augusta & Co merchant bank. “Only Greece sends proportionately more waste to landfill than the UK.”
The real driver for change, however, is cost. Ten years ago, landfilling was still cheap, maybe £10 a tonne. Today it is about £70 a tonne. The cost has been pushed up by the government’s “landfill tax escalator” — it rises £8 a tonne every year — and by the increased cost of engineering landfills so that they comply with stricter environmental regulations. According to the Audit Commission, Britain could run out of landfill capacity within seven years anyway.
For a company like Sainsbury, it’s a bearable cost. But for smaller firms and, more importantly, local authorities, which are saddled with handling more of the country’s waste than any other group, it’s painful. According to Dustan at VT, 18 projects from councils will be put out to tender in the coming months.

Indeed, the company won planning approval late last year for a new waste-management facility that will recycle, digest, compost and generate electricity from 200,000 tonnes of rubbish from Wakefield council.
VT is also one of five bidders vying for a 25-year, £500m contract from the Portsmouth naval yard to build a plant that converts commercial waste into energy that will one day be used to provide power to the Royal Navy’s new aircraft carriers when they are in port. “The targets have come up a bit on people. They have known about them for a while, but it takes two years to run a competition and another two years to build a facility. Now they are scrambling,” said Dustan. “People are going to have a hard time meeting the targets.”
The Isle of Wight offers a glimpse of the future. In November, the waste company Biffa began diverting some of its lorries to a newly opened “gasification” plant, the first of its kind in Britain. With funding from a government technology demonstrator fund, the independent technology group Energos converted an old incinerator into a plant that heats waste to about 1,000C in an environment with minimal oxygen. The waste doesn’t burn; rather, it melts down, releasing a gas and leaving solid material. The gas is used as a fuel for a small power plant.
The plant would not have been possible without the Renewable Obligation Credit (ROC) scheme, a government subsidy programme that is one of the most generous in the world. Under the energy bill, which takes effect in April, companies like Energos will receive two ROCs for every megawatt of power produced using “advanced recovery technologies”, such as anaerobic digestion, gasification and pyrolysis.
These credits, which companies can sell to other power generators that exceed their pollution allocations, are worth about £50 per megawatt-hour (MWh). As advanced-technology firms get two ROCs per MWh, it roughly triples the income they can collect from electricity production — currently about £55 per MWh. It is the carrot to the landfill tax “stick”. Street said: “Between ROCs and the landfill tax, we’re rapidly reaching the point where it gets cheaper to do something different with waste.”
The ROC scheme was intended to get projects like the Energos one off the ground. Gasification is more efficient and cleaner than other options such as incineration, the preferred method of waste disposal in many continental countries, such as France. Grimshaw said: “If you imagine a bonfire, all the bits won’t burn. Some will be wet or too dense and they will be left over. That’s incineration. Gasification is like using a gas stove. The key is being able to control the reaction. There is no ash, no residue.”
Novera, the publicly quoted renewable-energy group, plans to build this year what would be the second such facility in Dagenham, Essex. It would gasify material provided by the Shanks waste company in east London to generate 13MW of electricity, which would be sold under contract to Ford to power its nearby engine plant.
Like Inetec, however, Novera has to find someone willing to bankroll the project. Gasification is a fairly new technology and its large-scale economics have yet to be tested. The worry is that despite the financial muscle the government has thrown behind the cause, the harsh reality of a recession has decreased the urgency, and the money, that such climate-driven initiatives attracted even a few months ago.
For every sceptic, however, there is an evangelist. Christiansen said: “We have been very slack for a long time, but that just means that now there is a huge opportunity. It’s like the Klondike out there at the moment.”
Even your loo could be used to generate electricity
IF it is up to Tony Wray, your loo waste will one day help to keep your lights on.
Yes, the chief executive of the water giant Severn Trent wants to convert Britain’s flushings — “sludge” in industry parlance — into a renewable-energy source.
“When it goes on to land now, sludge is 20% to 30% dry solids. If it is dried to about 80% solids, it becomes like a cake and has about half the calorific value of brown coal, even after we have taken the methane from it,” said Wray.
Making this a reality on a large scale is still some way off, but not for lack of trying. Wray has set up a research and development unit dedicated to advanced waste-to-energy technologies. However, his scientists have yet to perfect a method of drying the sludge that makes sense economically.
Wray has made some headway nonetheless. It takes a lot of power to pump water and waste through the company’s 32,000 miles of pipes. Electricity, already at record prices, is one of the group’s biggest expenses.
Yet last year, Severn Trent produced 17% of its own needs thanks to what Wray says is the largest fleet of anaerobic digestors in the country.
They break the solids sieved out of sewage into sludge and methane. The latter is used to fuel 34 combined heat and power plants.
And the former? Severn Trent uses the sludge as fertiliser on a 3,000-acre farm in Nottinghamshire where it will help to grow crops that will be used to supply energy rather than feed people.
Wray’s goal is to generate 30% of the company’s electricity needs within five years. Given that water companies will be among those that will be roped into the European Union’s carbon trading scheme, under which they will have to pay for emissions, it is more than a “nice to have”.
Wray said: “We’re going to get captured in the next phase of the carbon trading scheme, so the efficiency with which we can manage our energy consumption is very important.”