Exciting Opportunities Arising from UK Government Low Carbon Strategy

The following is an extract from the Enviros Consulting September 2009 Briefing Note on the UK's Low Carbon Strategy:

The UK government has announced a number of financial drivers and measures to remove barriers to deployment of more renewables, as part of their low carbon strategy.

This rapidly growing industry will bring opportunities for many of our customers. Nonfinancial measures include a new planning PPS, measures to improve grid access and a new Office for Renewable Energy Deployment.

However the main drivers announced are the financial ones outlined below.

The Renewables Heat Incentive

- The Renewables Heat Incentive will deliver a staggering 72TWh/yr of heat by 2020 from biomass, solar, heat pumps and biomethane
- The policy to be in place from April 2011
- It will give guaranteed payments to those generating heat from renewables – domestic through to industrial scales
- We should expect a fixed rate paid on energy yield and cost of plant – not on CO2 emissions saved

UK Government will consult at the end of this year on scheme details and on fundamentals including levels of funding and how the levy to fund it will work

Installations from 15 July 2009 onwards will qualify for payments though there will be environmental standards and a qualification scheme for installers.

Measures to support electricity from renewables

The plans for financial support for renewable electricity has been presented in a separate consultation paper

Renewable Electricity Financial Incentives.

There are some detailed changes to the Renewables Obligation (ROC) regime that will impact larger generators and are designed to bolster confidence in this support mechanism.

However, perhaps the most significant announcement is of a new mechanism known as Feed in Tariffs (FIT).

As presented in the consultation paper FITs:

• Will give significant payments to small scale renewables – up to 5MW but with much higher payments for micro-renewables
• Will come into operation from April 2010 with consultation closing Oct 09 (though schemes built from 15 July 2009 will qualify)
• Will support delivery of up to 2% of our electricity by 2020
• Will pay the tariff for every unit of generation (whether used on site or not) aiming to give investors 5-8% internal rate of return (IRR)
• A FIT contract would be for 20 years, index linked and transferable from person to person
• Fix the price that will be paid for power exported at reasonable level (5p/kWh suggested)
• Will be paid by those supplying the site with electricity to the site of generation.

Payments proposed are much higher than anything seen in the UK so far.

For example a householder installing a retrofit domestic scale solar panel would get 36.5p/kWh for all the generation from the panel, would enjoy free electricity from it while using it and would get a suggested 5p/kWh for electricity exported (income tax free).

Other Opportunities

The Low Carbon Transport Strategy and the Low Carbon Industrial Strategy will give other opportunities to those sectors of the industry.

The transport strategy proposes that the proportion of biofuels being blended with petrol and diesel be increased to 10% by 2020 in line with the EU directive.

This is a huge increase in the amount of liquid biofuels required and could offer opportunities for farmers.

However, it is recognised that there are potentially negative food security and environmental issues associated with this policy and we can expect increasingly stringent controls on sourcing of liquid biofuels.

The transport strategy also outlines measures to reduce transport emissions by:

• Improving the efficiency of new vehicles (cars, vans and buses)
• Electrifying more of the rail network
• Facilitating the use of electric vehicles – including the offer of financial support to purchase them
• Encouraging more walking, cycling and low carbon travel habits • Working on international agreements on shipping and aviation.

The Low Carbon Industrial Strategy recognises the opportunities for UK industry and commerce. To maximise the opportunities, the government intends to remove barriers to making the changes and has announced £405 million of support:

• £120 million will be used to develop offshore wind
• £60 million to develop wave and tidal power
• £6 million to contract “60 or more” low carbon affordable homes
• £10 million increase, from £20 million to £30 million, for electric vehicle charging infrastructure and £25 million Low Carbon Vehicle Demonstrator Programme • £4 million expansion of the Manufacturing Advisory Service
• £12 million for green chemicals/sustainable biotechnology
• £15 million nuclear advanced manufacturing research centre
• £150 million for UK Innovation Investment Fund -> £1billion in 10 years.

How Enviros can help

This is an exciting time for initiatives in the low carbon sector and with these recent papers, the Government’s direction and support is now clear.

With the ‘step change’ represented by these papers some projects that were not previously viable now may well be. Enviros have over 30 years of experience in this field so have the skills, knowledge and expertise needed to be able to support you as you work to make the ‘low carbon transition’ needed or capitalise on the opportunities presented, whether you are working in the public or the private sector.

Get your FREE copy of the full Low Carbon Strategy briefing document here.

Scottish Government and Scottish Renewables Calls for UK Treasury to Release Millions to Invest in Renewable Energy

Support for access to renewables cash grows

Scottish Renewables have joined the Scottish Government in calling for the UK Treasury to release up to £174 million to invest in renewable energy.

The money is currently held by Ofgem under the Fossil Fuel Levy arrangements, which mean the Scottish Government is unable to access the cash without a corresponding reduction in its budget.

Finance Secretary John Swinney has argued for the fund to be made available as additional money over and above the Scottish budget since this administration came to office in 2007.

And today the cause will gain the support of Scottish Renewables, when Niall Stuart, chief executive of the green energy trade body, addresses a marine energy conference in Inverness.

Mr Swinney said:

"This is £174 million of Scotland's money that should be invested in developing renewable energy in Scotland right now.

"Instead, the unwillingness of the UK Treasury to change its position means it is sitting unused in an Ofgem bank account in London. Scottish Renewables are absolutely right to be calling on the Chancellor to release this money so that it is additional to the budget already at our disposal.

"I welcome their position and can assure them we speak as one on this issue. It simply makes no sense that, at a time when the parlous state of the UK's public finances is well documented, and when Scotland is facing a 500 million pounds cut in its budget next year, this money is withheld and only available if we accept a corresponding reduction in Scotland's budget.

"Scotland has a flourishing renewable energy sector that could benefit hugely from this additional money.

"This Government is doing all it can to help - but with access to this funding we could do even more. That would not only bring the clear benefits of developing cutting edge renewable technologies, but would also support green jobs and help stimulate a strong economic recovery."

The Fossil Fuel Levy (FFL) is used to compensate power companies for the higher costs involved in meeting the terms of contracts to purchase renewable electricity, awarded during the 1990s under the previous support mechanism, the Non-Fossil Fuel Obligation (NFFO).

Changes introduced in 2005, which allowed the proceeds from the sale of Renewables Obligation Certificates (ROCs) attributable to Scottish NFFO contracts to be used to meet the FFL costs have led to the development of a rapidly accumulating surplus in Ofgem's bank accounts (the Scotland and England/Wales accounts being held separately).

Scottish Ministers and officials have raised this matter with UK Government counterparts on a continuous basis since May 2007. Treasury rules on Departmental Expenditure Limits (DEL) mean that FFL surplus resources, if released to Scotland, would not be additional to Scotland's block grant. To enable FFL funds to be used for additional activity in Scotland would require the Treasury's agreement to increase Scottish DEL equivalent to the amount being drawn down from the FFL. The Treasury remains adamant that should Scottish Ministers choose to draw down this money, a corresponding reduction would be made in the Scottish block grant.

Full articles at the Scottish Government web site.

Waste Produces Gas for Cooking in Kenya Using Anaerobic Digestion

This item shows how anaerobic digestion can be such a power for good. It brightened my day and I hope it does the same for yours as well. It explains how biogas is being used to solve a number of problems simultaneously in Kenyan slums.

Harnessing Waste Produces Gas for Cooking in Kenya
By Cathy Majtenyi
Kenya
From Voice of America News - 07 November 2009

The scourge of so-called "flying toilets" - where human waste is put into a plastic bag and tossed into the air, landing on roads or in gutters - has plagued the slums of Kenya's capital Nairobi for decades. But an innovative project in the slum of Kibera has dramatically cut down on the problem by converting human waste into gas that can be used to fuel cookers and other devices.

Roseline Amondi is cooking up a storm. Today's menu for the tiny restaurant she runs is githeri, a traditional dish consisting of beans and maize.

Amondi cooks every day in this community kitchen. She will then take the food back to her kiosk to sell to her customers. She says the community stove saves her a lot of money that she would otherwise spend on charcoal or wood.

"Before the gas started working, I was using almost 100 or 200 [shillings] per day for cooking any meal in the house, but right now, it is only 10 bob [shillings] per meal," she said. "It is very cheap. If I cook two different types of food, I may use only 30 shillings for the whole day. That is wonderful."

The gas that Amondi uses comes from an unlikely source, the community toilet. This is a rare sight in Kibera, where up to 200 people can share a single latrine in neighborhoods that have no electricity or running water.

The toilet and kitchen are run by a coalition of five community groups calling themselves TOSHA (Total Sanitation and Hygiene Access). "Tosha" also means "enough" in the national language Ki'Swahili.

Some 600 people a day use the toilets for a small fee.

The human waste is transported via pipes into an underground tank, where it is converted into bio-gas.

The gas is then piped up to the community kitchen, where members can use the stove for pennies per pot.

Groups often rent out the facility's top floor for meetings and functions. TOSHA earns some $400 each month renting out the facility, the community kitchen and use of the toilets.

Aidah Binale is a coordinator with Umande Trust, a development group that partnered with TOSHA to formulate the project.

She says it was difficult at first for community members to accept the gas.

"People will have the idea of, 'Ah, no, I can't cook from there, it is from [human] waste.' Right now we are still trying to capacity build, we are trying to tell them [there is] nothing wrong," she explained. "We get to have more visitors from different countries coming to visit us. We make sure that when they come to the office, we tell them, 'Let's go down there and have tea.' So when the community comes and sees us drinking tea, they are thinking, 'Ah, this is a foreigner taking tea. These people are taking tea, we can also cook.'"

Running water and sanitation facilities are virtually non-existent in slums like Kibera, where most people earn less than $1 a day. Human waste in plastic bags is often dumped on roads, alleys and gutters.

But locals say there has been a dramatic reduction in these so-called "flying toilets" since the bio-gas center was constructed two years ago.

Roseline Amondi is also secretary of TOSHA.

"At the time we were using flying toilets, there were so many diseases around us like cholera," she noted. "Once an outbreak of cholera occurs, we are the sufferer. Many of us died, some got into the hospitals. But right now, for the last three months, there was an outbreak [of cholera] within Nairobi, but we were safe because of the bio-center."

Project supporters say the TOSHA Bio-Gas Centre is a model for communities everywhere, especially those dealing with power shortages.

Paul Muchire, communication manager with Umande Trust.

"We have the problem of [supplying enough] energy. Poverty levels are going up. Sanitation is a problem in the developing world. We have the issue of pollution from the oil and diesel. There is need to go into other sources of energy, adapt other sources of energy that would be environmentally friendly," he said.

Muchire says there are about 10 bio-gas centers in Kibera under construction and that an engineer is looking at how the gas can be piped into peoples' homes.

Anaerobic Digestion Has Big Role in Zero Waste Britain Announcement

The path to Britain becoming a zero waste nation was announced last week by Environment Secretary Hilary Benn at a summit of Local Authorities and the waste industry.

Hilary Benn said:

"We need to rethink how we view and treat waste in the UK. Why do we send valuable items like aluminium and food waste to landfill when we can turn them into new cans and renewable energy? Why use more resources than we need to in manufacturing? We must now work together to build a zero waste nation - where we reduce the resources we use, reuse and recycle all that we can and only landfill things that have absolutely no other use.

"To do this all of us - government, local authorities, businesses and consumers - must do our bit. And we must make this moment the turning point on our journey to eliminate wasteful waste.”

During a morning visit to Earls Court, Mr Benn showed his support for an updated BSI sustainable event standard which is designed to ensure that the events industry considers the social, economic and environmental impacts of their events.

Mr Benn continued:

"Using new technologies will help us to re-use things, for example anaerobic digestion that creates energy from food and farm waste. And businesses can apply the technology at their fingertips to design innovative products that use less resources or contain recycled materials.

"In ten years time 75 per cent of household waste will either be recycled or used for energy, and over time this figure will increase even further. Aiming for zero waste is the way we have to think to get us to where we need to be."

Secretary of State for Communities and Local Government John Denham added:

"If we continue to send recyclable or compostable waste to landfill we are missing a major opportunity to generate heat and energy and missing an opportunity to turn that waste into money. We can save planet whilst keeping money in resident’s pockets.

“I have recently set out ambitions for councils to play a bigger role in tackling climate change and thinking more creatively about waste is just one way to unlock that potential.”

Setting out how the UK can become a zero waste nation where people can do the right thing with their waste whether at work, home or on the move, Mr Benn said:

* England should more than halve the amount of waste going to landfill in the next 10 years – early next year we will consult on what recyclable and compostable items should be banned from landfill and how a ban will work.
* In ten years time 75 per cent of household waste will either be recycled or used for energy, and over time this figure will increase even further.
* Six new Zero Waste Places in parts of Shropshire, Dorchester, Brixton, Newham, Hoxton and Suffolk will be created to develop innovative ideas to cut waste in the home, workplace and community.
* A new Zero Waste Places Standard for Local Authorities will also recognise areas which are going above and beyond national waste targets while supporting them with small grants for further development.
* New research out today shows it is possible to divert 500,000 tonnes of household waste per year through re-using it.
* Later this month a new public campaign will be launched, aimed at encouraging people to rethink their approach to waste by reducing and reusing the waste they create as well continuing to recycle as much as they can.
* The Government expects Local Authorities to offer a full collection service for all recyclable items by 2020. This should include paper, card, cans, glass and plastic bottles, food and packaging. We will encourage Local Authorities in collecting food waste to make use of the technology and funding available to them to harness the power of energy from waste.
* Publication of our aims and actions for Commercial and Industrial Waste in England. This will help businesses to use resources more efficiently and encourage them to think about what they do with their waste as well as delivering benefits for the environment. Actions cover four areas: helping business; working with the waste management industry; plugging the data gap; and encouraging innovative approaches.

Food Waste Recycling Company PDM Group Announces Council Talks

Food waste recycling company PDM Group has revealed that it is in talks with "a lot" of councils about the treatment of separately-collected food waste as it looks to secure the feedstock for its network of planned and existing biomass and anaerobic digestion facilities.

Speaking to letsrecycle.com last week (September 17), the company's commercial team manager, Suzanne McDermott, said that its current priority was making councils, food retailers and food producers aware of the energy potential of food waste.

The calorific value of food waste means it's absolutely perfect for producing energy

Suzanne McDermott, of PDM said:

"The calorific value of food waste means it's absolutely perfect for producing energy," she said, explaining that "we're telling local authorities, commercial food companies etc. that its worthwhile getting it source-segregated to get that energy out of it."

She added that PDM was now talking to "a lot of councils", noting that some local authorities were currently composting a "small proportion" of food waste alongside green waste.

However, Ms McDermott acknowledged that there would be a "cost implication" for councils that did decide to introduce source-segregated collections of food waste.

PDM has traditionally drawn the majority of its customer base from the commercial food and catering sectors, and in January 2009 it signed a 'long-term' contract to deal with all Sainsbury's food waste (see letsrecycle.com story).

Energy Generation

Earlier this year, the Doncaster-based company also revealed that it had plans to invest £110 million in the energy generation side of its activities, including building a number of anaerobic digestion (AD) facilities (see letsrecycle.com story).

In June 2009, it set up a joint venture, known as ReFood UK, with German AD specialists SARIA Bio-Industries to establish the facilities, the first of which is expected to be up-and-running in Doncaster early next year.

Ms McDermott explained that "we have gone with the German model because it's solely for treating food waste," and added that "what's already in the UK is working well but it's mainly for agricultural purposes".

Outlining the company's exact plans with regards AD, she said that it aimed to develop "a further six AD plants over the next five years which map us out across the country", with each facility offering the capacity to treat up to 45,000 tonnes of food waste a year, producing 2MW of electricity.

PDM also has two biomass waste-to-energy facilities - in Widnes and Rushden - which use fluidised bed combined heat and power technology to treat meat industry residues, and a network of rendering facilities, and Ms McDermott explained that "whatever's closest becomes the first port of call" as the company looked to reduce the carbon impact of treating the waste.
Outputs

With regards the outputs from the ReFood AD process, she acknowledged that "sometimes farmers might not want it, so the alternative is to put it straight into the CHP," explaining that "we always have to have a back-up, we have always got the alternative - we can send it to our rendering or energy plants."

PDM is currently in talks with farmers located near to the Doncaster site about using the digestate produced by the AD process, and the company has previously said that it will look to gain the PAS110 standard for the digestate when the facility is up-and-running

Monsal Obtains Planning Permission for their Food Waste Anaerobic Digestion Plant in March

This follows up on our recent post about Monsal to bring you an update from them, when planning permission is obtained in very quickly time.

Monsal in commenting on the success of the planning process said:

“Planning was achieved in record time for this project. It was the result of our co-operative and very detailed approach to the planning/permitting process. We support biowaste AD projects from concept through financial close and subsequent delivery having the largest specialist team in the UK in this area. We operated as an integrated team working with Local Generation and the regulatory authorities to ensure the project and technology complies with all relevant environmental standards. This avoided abortive work and ensures that the overall solution can be fast tracked into the construction phase with a guaranteed delivery cost.”

The biowaste to energy concept is now being widely applied for the conversion of commercial and household food waste to biogas. The Monsal technology platform is well established and has been operational on large food waste and household kitchen waste treatment and recycling plants for over 10 years in other countries in Europe.

Aidan Cumiskey Monsal’s Managing Director said:

“This is a great result for Local Generation and Cambridgeshire. Lifecrown are a forward thinking group and the plant will neatly integrate local biowaste recycling with on site renewable energy production and create additional employment in the Cambridgeshire/Peterborough area. Based on our latest technology the plant can treat a large variety of biowaste streams including kitchen and household food waste and convert them to renewable energy. This is our first major success with the food sector and we expect continued uptake as a “greening” of the UK food industry supply chain takes place in the coming years.”

AD Contractor Monsal Announces Food Waste Plant for Cambridgeshire, UK

The specialist UK Anaerobic Digestion Plant Contractor Monsal has now completed the planning phase for new food waste anaerobic digestion and renewable energy plant in Cambridgeshire.

Monsal have now completed the first phase of planning, pre-design, permitting and support services for an advanced food Anaerobic Digestion (AD) and renewable energy contract in March, Cambridgeshire. The project is for Local Generation Limited, a subsidiary of Lifecrown Investments Limited and will be located on land owned by Lifecrown and adjacent to Local Generations sister company Fenmarc Produce, a leading vegetable food packager and processor. Monsal expects to deliver the turnkey AD contract once permits are in place in late 2009 and the project will progress into the construction phase in early 2010.

Food waste from a range of food businesses and some potato waste from Fenmarc will be processed and recycled by the latest Monsal technology to provide a high grade compost and generate renewable energy from biogas. This will divert food waste from landfill and lower emissions of harmful greenhouse gases in the process.

The plant is expected to produce up to 2.5MW of electricity and heat from a combination of potato waste produced at the Fenmarc site and other locally sourced food waste, which currently goes to landfill. Local Generation intends to sell both the power and heat to local homes and businesses, including Fenmarc. In addition to these outputs, the plant will produce up to 12,000 tonnes a year of high quality soil conditioner suitable for improving local Fenland soils. The plant will create some 10 to 15 new jobs once operational and is the largest plant planned in the region.


The project will generate sufficient electricity to supply 1,500 homes, or approximately 6% of the total demand for March, including that from industry and commerce. By so doing Local Generation will help Fenland play a big part in meeting the UK target of 10% of power generated from renewable sources by 2010 and the EU target of 20% of all energy from renewables by 2020. A modern plant such as this can capture over 80% of the energy content of its fuel.

Mark Harrod, Chairman of Lifecrown said:

“The success of our group companies in Fenland for 40 years has been founded on the strategic location and the skills and work ethic of the local workforce. In making this further substantial investment I am confident that these factors will, once again, get us off to a flying start. This project addresses two of today’s most pressing problems; climate change and food waste management. By treating energy as a precious resource we can maximise value for all concerned.”

Monsal offer a complete turnkey service from consultation, planning, design, permitting with subsequent technology delivery once planning permission and permits are in place.

On receipt of planning approval for the March plant on 17th September, Local Generation director Nick Waterman said “We are delighted that Local Generation Limited has today been granted planning permission for its AD plant at Westry, March.

We are very excited at the prospect of contributing positively to the environment by reducing waste to landfill and lowering emissions of harmful greenhouse gases in the process. The UK Government wants businesses like ours to invest and create new jobs in green technologies as well as deliver sustainable solutions and that is exactly what we are going to do.

This is a great day for Local Generation and our team is looking forward to building the plant. We hope that people in March, Fenland and Cambridgeshire will be very proud to have one of the first AD plants in the UK operating in the region.”

Aidan Cumiskey Monsal’s Managing Director said:

“This is a great result for Local Generation and Cambridgeshire. Lifecrown are a forward thinking group and the plant will neatly integrate local biowaste recycling with on site renewable energy production and create additional employment in the Cambridgeshire/Peterborough area. Based on our latest technology the plant can treat a large variety of biowaste streams including kitchen and household food waste and convert them to renewable energy. This is our first major success with the food sector and we expect continued uptake as a “greening” of the UK food industry supply chain takes place in the coming years.”

Commenting on the success of the planning process:

“Planning was achieved in record time for this project. It was the result of our co-operative and very detailed approach to the planning/permitting process. We support biowaste AD projects from concept through financial close and subsequent delivery having the largest specialist team in the UK in this area. We operated as an integrated team working with Local Generation and the regulatory authorities to ensure the project and technology complies with all relevant environmental standards. This avoided abortive work and ensures that the overall solution can be fast tracked into the construction phase with a guaranteed delivery cost.”

Maximising the Value of Sewage Sludge Biogas - Study Reports

The September 2009 edition of the Newsletter of UK Water Industry Research Limited, leads by reporting on their study into "Maximising the Value of Biogas". We thought that it contains some really interesting pointers to those involved in planning and running Anaerobic Digestion facilities, so we report on it in this posting.

Biogas has for some time been employed by the UK Water industry as a source of energy for combined heat and power plants.

The employment of biogas becomes more attractive as advances in technologies for biogas production, treatment and application, mixed with new financial inducements for various kinds of renewable energy progress. Optimisation of biogas production and use will also bring ecological benefits, including helping the water industry mitigate its global warming impacts.

The UKWIR project Maximising the value of Biogas, managed by Gordon Wheale, gives a clear appraisal of the technologies and the expenses concerned in maximising the earning potential of biogas produced from the digestion of sewage sludge.

It inspects the advantages stemming from biogas optimisation and possible 'regulatory blockers'.

At an UKWIR project dissemination workshop, representatives heard from James Newton of the contractor, Mott MacDonald, the technology needed for conversion of biogas to biomethane is well established and commercially available.

Conversion of biogas to biomethane makes accessable all of the applications of natural gas including injection into the nation's gas grid or use as an automobile fuel.

Such uses are well established in mainland Europe and a number of states around the world. While technically possible, there are not many examples of sewage biogas being converted to hydrogen ( for combustion or use in fuel cells ) as these are typically extremely expensive both in term of capital and operational costs.

With new developments in hydrogen technology, this will (they expect) become an enticing option in the future.

Conclusions

This research discovered that the use of biogas for CHP generation for on-site use would, usually, achieve the best worth for a water company. CHP is a mature technology with proved commercial benefits and the best systems can convert up to forty percent of the energy contained in biogas into electricity.

The utilization of biogas as a fuel for autos also achieves a comparatively high worth and, in some circumstances, higher than that achieved for biogas CHP. It also brings ecological benefits compared to standard fossil auto fuels.

Sensitivity of the values that can be derived for different biogas uses is found to be extremely variable arising from only minor changes in guesses. They found that in particular, the values of the renewable energy drivers available ( which in a few cases are still to be established by secondary regulation ) and the impact of the 'Carbon Reduction Commitment' gave big changes in value.

Also they are sensitive to site explicit factors. These include the supply of biogas for other uses, the leftover cost of existing investments in CHP assets and the distance to the local gas grid. So a site explicit survey should be carried out when thinking about alternative biogas applications.

The research for this report reveals that different biogas uses can have broadly similar values. Therefore , for many sites, optimizing biogas production may achieve larger financial and environmental advantages than changing the output use."

For further information get the September Edition of their Newsletter by using the link below:

http://www.ukwir.org/publishor/system/component_view.asp?logdocid=93032

Through Anaerobic Digestion Sewage Sludge Becomes Energy Provider not an Energy User

In an energy dependent world, sludge should be an energy provider not an energy user. Keith Panter of Ebcor argues in favour of projects where energy cost/benefit rather than disposal becomes the major project driver. He also promotes the raised AD conversion rates achieved by what he and Cambi describe as "advanced digestion with thermal hydrolysis".

The following article is based upon an article in Water and Wastewater Treatment August 2009 edition. In that article Keith Panter has highlighted the need for homespun energy as the UK finally passes from the age of UK energy sufficiency into dependency upon supplies from overseas, and not only that but dependency on supplies from nations which have been politically unstable in quite recent times.

He highlights the welcome fact that following a recent review of energy policy, Dwr Cymru (Welsh Water) has decided to reduce its reliance on energy intensive thermal drying of raw sludge at three Wastewater Treatment Plants in South Wales in favour of anaerobic digestion (AD) and power generation at Cardiff and Afan.

The energy these AD plants will generate is high compared with farm waste type AD plants, and the aim is to generate 5MW of green power by March 2011 to grandfather the value of the Renewable Obligation Order Credits (ROCs). Apparently a technical and commercial review of pre-treatment technologies for AD has led to the selection of Cambi as the THP provider. The operator is Kelda who and they were consulted as part of the decision.

What I find remarkable is that he informs us that when complete, eight Cambi plants in total then operating in the UK and Ireland will be treating sludge from the equivalent of a 6M population. That’s almost a tenth of the United Kingdom population!

So, it reinforces me in the view that already in a short period of 5 years since I started to write about Anaerobic Digestion in my www.anaerobic-digestion.com web site, Anaerobic digestion has progressed from a novelty seen as largely just a sludge treatment and farm waste disposal process, to a main stream renewable energy producer.

Of course, it has been the rapid development of economic driving forces (drivers) which have moved the agenda forward at such a pace, and in recent years government incentives such as ROCs that have given the final push to propel AD into the limelight.

Back in March 1999, the Economist magazine (UK, London) predicted that energy prices would remain stable for the foreseeable future. How wrong could they have been?

Water treatment professionals got closer to reality, Keith says, when in a straw poll at the 1999 European Biosolids conference they were asked what they thought, and predicted a doubling of energy prices within ten years.

In reality the wholesale price of natural gas that was about £6/MWh at that time rose to over £20/MWh in the time period.

Ebcor has clearly for 10 years and longer, been looking in depth at the process cost model for sludge drying. He also evidently demonstrated at that same conference 10 years ago that investment in raw sludge drying would be misplaced if the price of energy even only doubled.

He explains that it takes about 1 MWh of energy to evaporate 1 tonne of water - so in general at that high an energy cost it is much cheaper to haul water in un-dried sludge cake than to evaporate it in a dryer.

The same model has apparently shown that the magnitude of the carbon footprint is more or less related to process cost as most sludge process costs are primarily energy related. Ebcor concluded at the time that advanced digestion (such as using the Cambi process with thermal hydrolysis) would give the best whole life cost and the most flexibility and would safeguard utilities from future energy price hikes.

The non financial justification of raw sludge drying is the flexibility offered by producing a potential fuel. Keith points out that this surely applies if markets do not exist for biosolids products but in reality these markets have remained stable and in some cases improved as biosolids quality has improved.

The UK safe sludge matrix was developed about the same time and has been a big help in securing biosolids' place in agriculture.

So, there it is. Yet another Anaerobic Digestion expert is in effect demonstrating very clearly that the day for AD has arrived. Are you using Anaerobic Digestion, or still drying WWTW sludge?