It’s an important milestone for any young anaerobic digestion (AD) plant; commissioning involves a series of thorough tests to ensure that the plant – and the team that runs it – are both working to the highest standards of efficiency and safety.

During commissioning we’ve already processed over 900 tonnes of waste – from households, food manufacturers and retailers and we’re now producing biogas. Just as a car needs the right quality of petrol to ensure that it performs to its highest standard, our combined heat and power engines need top-quality food waste biogas to perform at their full potential. What happens next? We’re going to:

• monitor the quality of the biogas produced by the AD process
• test the engines and the connection to the Grid
• beam green energy directly to sister company Fenmarc Produce Ltd
• send any surplus electricity to the National Grid

We’ll keep you updated as we prepare to switch on this great new source of sustainable energy!

Planning, building and testing – it’s a very busy time for the teams here at Local Generation as our first anaerobic digestion (AD) plant takes shape in March, deep in the Cambridgeshire countryside.  Yet the process the plant is designed to host is simple, and the end product is a natural wonder.

After waste food has been partially broken down by one micro-organism population and pasteurised, it’s then ‘digested’ by more micro-organisms.  The result is biogas, high in methane and similar to natural gas.  Stored in the big biogas dome at the plant, the gas has many potential uses:

• as cooking fuel
• in combined heat and power (CHP) gas engines
• upgraded to biomethane of natural gas quality
• to replace fossil fuels

Because we’re situated close to the National Grid, we’ve decided to generate electricity using two CHP engines (the photo above shows them being installed).

AD facilities mean bonuses for the economy and our ecology, because they cost less to build and run than big power plants, and are cleaner.  As the demand for climate-friendly energy continues to grow, we’re proud to think that our plant is providing an efficient energy alternative!

The latest landmark to be put in place at Local Generation’s anaerobic digestion (AD) plant in March, Cambs, is the impressive biogas dome. Made from the same sturdy stuff that’s used to float lifeboats in stormy seas, the container is designed to store almost 4000 cubic metres of biogas.

Around 60% methane and 40% CO2, biogas is the end product of the AD process.  However, it doesn’t stop there.  The big white dome simply holds the biogas until it’s ready to go to the combined heat and power engines that will convert it into green electricity, for use at sister company Fenmarc and to be fed back into the national grid.

We’re on track for commissioning the plant in the next couple of weeks and fully up and running early next year.

I was delighted to be a guest at the annual Fenland Enterprise Business Awards (FEBA) earlier this month to present produce firm Greenvale AP with FEBA’s Green Award. This is the second year running that Local Generation have sponsored the green award and the entries are getting better each year.

Greenvale AP won this year’s award with environmentally friendly improvements such as the introduction of LED lighting on their site, and a bespoke water recycling system.  Group environmental manager Jessica Cranthorne said that the company wanted to become “a truly sustainable Fenland business.”

All of us at Local Generation are pleased that companies in the region are setting such high standards for sustainability.

Reducing local landfill by 30,000 tonnes a year was a goal worth pursuing.  But now our anaerobic digestion (AD) plant in Westry, March, has been granted planning permission to up its capacity to an impressive 70,000 tonnes, to be phased in over the next few years. That’s 70,000 tonnes a year that won’t go into landfill and a huge reduction in resulting greenhouse gas emissions.

It was a nine-to-five day with a difference last month when the Local Generation team swapped computer screens for gardening gloves.  That’s how long it took ten teammates to put in 8,000 green and glossy sedum plants around two-thirds of the bund (the two-metre high clay and soil barrier around the plant’s tanks).  There’s not much to show for it yet, (other than a few aching muscles) but in two years time the plants will grow into an attractive and weed-resistant green ‘coat’ for the bund.  All part of Local Generation’s green-fingered approach to its Anaerobic Digestion (AD) site in March.

Next time you drive past a large container tank set back from the road, look out for a protective barrier built right round it, with gently sloping sides, made of concrete or earth covered with grass, that’s a bund.

In Britain, as in many other countries, bunding is compulsory around tanks storing oil, fuel, or other liquid substances – in this case the liquid in the digestion tanks. Bunds are designed to contain any spillages safely within their walls.

The two-metre high bunding around the main part of the site is made of 3346 tonnes of  engineered clay topped with soil, and in line with Environment Agency requirements, is able to hold 110% of the tank’s volume of liquid.

From one kind of environmental protection to another: the photo above shows the Reception Hall taking shape. At 25 metres x 25 metres, and around 10 metres high, this building will be an important part of the process. Lorries will drive right in and offload their waste food on to the floor of the hall.  Here it will be de-packaged and loaded into the process by our colleagues, for a quick, clean and efficient start to the AD process.

Finally, Local Generation is out to prove that ‘good for the environment’ can also be good-looking. Work started in August on planting the bund with over 14,000 green and graceful sedum plants. These succulent plants (they store water in their leaves) come in a huge variety of leaf forms and flowers and together with the clay and soil bund, provide an eco-friendly alternative to concrete. “We’re going to make the planting project into a powerful team-building exercise,” says Sales, Marketing and Technical leader Dawn Terry. “It’s all part of building sustainability into everything we do at Local Generation!”

Earlier last month, the Local Generation team returned from the Anaerobic Digestion and Biogas Association’s (ADBA) second Annual summer Conference and Gala Dinner informed and inspired…

Delegates from ADBA’s member organisations were there to engage in debates, masterclasses and workshops for farmers, food producers and others with an interest in anaerobic digestion. With topics like ‘Loving Your Bugs’ and “Electricity from Biogas’, the seminars and gala dinner were well attended and buzzing with positive energy to grow the Biogas industry in this country from the 54 AD plants currently operating.

Highlights of the conference gala dinner included ADBA’s announcement of a collaboration with youth and sustainability charity Raleigh International.  This exciting project is teaming anaerobic digestion professionals with Raleigh’s young project teams, setting up domestic-scale AD plants in remote rural locations in countries including India and China. These projects enable households to convert their domestic waste into energy that can be used for cooking and heating, and by-products like non-synthetic fertiliser for growing better crops.

“One of the hot topics at the conference was digestate and how to make the most of it,” says Sales and Marketing director Dawn Terry: “With a network of local growers in the community, through our sister company Fenmarc, we’ve got a ready-made outlet for this valuable soil improver.”

Another idea with big potential is to channel bio-methane from AD direct into the national gas grid to safeguard against the future decline of UK gas supply, though at the moment, says Dawn, “technology costs need to come down to make this viable.”

As work continues at Local Generation’s AD plant in March, Cambs, sharing new ideas and networking with other AD professionals in this ever-evolving field will generate more opportunities to develop our business and this industry further – so here’s to ADBA 2012!

The grandly named Process Aeration Filtration tank actually has a simple but vital role: to help clean the water that will be removed from digestate as it is processed in the digestion tank.  And its mission doesn’t stop there – the clean water is then recycled back into the digestion process.

This nondescript metal box is the bio-filter, another vital component for the AD plant. 80 tonnes of wood bark lining the filter will bond with a ‘bio-film’ to act as a giant ‘odour-eater’ while the air in the waste reception hall is changed up to 18 times an hour.  In line with the sustainable values practised at Local Generation, after seven years the bark will be recycled back into the AD process rather than going into landfill.

Any odour remaining after air has passed through the biofilter doesn’t stand a chance once it reaches the elegant but highly efficient odour stack. Extensive air modelling checks by the Environment Agency dictated the height of the stack.

That’s all for this post.  Next time, we’ll be reporting on the headlines and highlights of the second UK AD & Biogas Conference, which Local Generation is attending on the 6th and 7th of July at the NEC in Birmingham.  We’ll be hearing from senior figures in government and industry about the latest developments in this exciting new source of green energy – and reporting back!

The pasteurisation tanks are now in place. Inside these streamlined yet powerful tanks, the liquidised food mix will be treated at a balmy temperature of 70ºC for a minimum of one hour. In a process similar to milk pasteurisation, this reduces the levels of undesirable bugs in the mix. The digestate that emerges at the end of this process can be spread safely on agricultural land.

No, it’s not a visiting UFO! But still, pretty exciting – a shot of our first digestion tank roof being built. This tank is where the liquidised food is heading once pasteurization is complete. The main part of the AD digestion process takes place in this tank. It’s also where the majority of biogas, rich in methane, is generated.

The methane gas produced by the AD process generates electricity using combined heat and power engines. Some of this energy will be used to operate the AD plant as well as providing green electricity to our sister company, Fenmarc Produce Ltd. Any surplus will be exported to the National Grid via the ‘export cable’ that’s being installed in the photo here.

By the time the plant is fully operational, it’s expected to divert up to 30,000 tonnes a year of food waste from landfill. This will help to lower both greenhouse gas and CO2 emissions.