Bristol’s new city history museum runs on wood pellets. It’s heated by a biomass boiler, part of a masterplan to reduce the council’s carbon emissions.

The green boiler is one of a number installed in the area, designed to improve the museum’s energy efficiency. It is part of Bristol’s 10:10 campaign: a 10% drop in CO2 emissions by the end of 2010. The council has established a local wood-energy supply chain, from recovering the wood chip through to installing biomass boilers in public buildings.

The wood fuelled boilers provides carbon neutral heat to the museum. While it still releases CO2 when burned, the wood only emits the amount of CO2 that the trees absorbed when growing, roughly equal to the amount they would have released when they decayed.

In the 21st century the holy grail is a truly green, carbon neutral fuel source. Most alternative projects struggle to achieve even modest efficiencies, not for want of scientific innovation, but because delivery to the end user dents the overall rating. The ultimate solution is one that can marry an advanced process with a local resource.

Wood chip is a by-product of tree management everywhere and viewed like any other low grade industrial waste, as an inconvenience. But wood chip is rich in natural energy, if only it can be liberated efficiently. As a fuel it presents an obvious challenge: it’s wet. Conventional methods of extracting energy from fresh wood generate more steam than electricity. This is where gasification comes in. A new generation of burners have rewritten the rule book on converting raw material into heat.

Where we’re going we don’t need roads

Gasification is complicated to explain as it is essentially a chemical reaction. Remember the end of Back to the Future when Doc returns with his DeLorean and feeds rubbish into the engine before taking off into the sky? Well gasification can turn rubbish into energy – not quite as simply as he did though! The feedstock (what you feed into the process) must be carbon-rich, like coal or wood. It undergoes a process involving the injection of oxygen, air or steam, while subjected to high pressure. The process can produce a flamable gas (hence ‘gasification’) which can even power vehicles (maybe not time machines!), but in the case of wood chip boilers the gas is burnt to produce heat.

The great advantage of gasification is that it is very green and some of the newer processes have remarkable efficiencies of 80% and above, compared with traditional processes that struggle to achieve half that. The cost savings from using wood fuel can be between 25% and 50% less than a fossil fuel system. So householders could make savings of around £500 a year and businesses could easily be saving tens of thousands, if they converted to wood fuel.

This technology has a very bright future and since the fuel doesn’t have to travel very far, it has the potential to offer some truly sustainable solutions to our future energy requirements.

Bristol City Council picks up awards for its commitment to tackling climate change. It was named the UK’s ‘Most Sustainable City’ and was the only UK city to be short-listed for the European Green Capital Awards. But they’re not alone in the South West, in fact the Regional Development Agency was awarded £3 million in April 2008 by DEFRA (the Department for Environment, Food and Rural Affairs) to invest in 30 bioheat projects. Once these are all up and running they will provide the region will be in excess of 37MW of renewable heat and save an estimated 7,000 tonnes of carbon a year.

If you’re interested in biomass and gasification energy sources, these links may be of interest:

Centre for Sustainable Energy helps people and organisations meet the challenges of rising energy costs and climate change

Bristol City Council Biomass Study

Renewable Energy Association

The BIOMASS Energy Centre owned and managed by the UK Forestry Commission, via its research agency Forest Research

Bristol Green Capital programme

Regen SW

South West Wood Shed run by Regen SW

Commercial:

UK Biomass Ltd a sustainable fuels project management company

Biofuels Media Ltd runs various study tours to BioEnergy facilities

Wood Energy Ltd is a leading specialist supplier of high efficiency automatic wood heating systems

We look after clients all over North London, and their trees and gardens. Of course our clients want the best care for their trees, but they also want their garden to survive, and their home. Often access is tight or the work might jeopardise a green house or conservatory. Our standard working practices ensure there is no damage to the house or surroundings.

We will happily assist in negotiating with insurance companies, loss adjusters. Naturally we work closely with planning officers and property maintenance professionals. Every day we are in contact with local authorities regarding Tree Preservation Orders and Conservation Areas before work begins.

We provide full liability and indemnity cover and carry out full checks .

I live in a terrace house

Over the 25 years we’ve been doing residential tree care we’ve worked round some of the most delicate situations. So many of the homes in London are terraced, which means access to the garden is only possible through the house. We have evolved careful practices to ensure there is no damage to the house as we remove the debris, however tight the access.

My tree is protected but it blocks out all the light in the kitchen

If a tree has a protection order on it there is limited work that can be done on it. However, we have close working relationships with the Tree Protection Officers in all North London boroughs and we are approved to undertake sensitive work in protected areas.

Tomlinsons have ongoing contracts with property developers and management companies. From basic seasonal tree care in parks and communal gardens to full gardening and landscaping services.

We have £5 million public liability insurance, £500,000 professional indemnity insurance and our staff have unlimited employers liability insurance cover.

All debris is recycled into wood-chip and used in highly efficient gasifying furnaces to heat local schools and businesses.

Our children are inheriting a natural landscape that is barely surviving the demands of commerce and population. We’re beginning to realise the vital role vegetation plays in our own survival. Education has been the force that’s made the difference. The younger generations are growing up with a far more sensitive and responsible relationship with the natural environment.

Since 1984 Dick Tomlinson has run programs in schools to engage children with importance of trees, and encourage them to plant trees of their own.

Tomlinson School Tree Care Workshop

The children are introduced the contribution of trees to the health of our environment. This is an entertaining and educational slide show.

There follows a session in the grounds or surroundings of the school, where individual stories are told about the trees growing there. This includes practical techniques for aging a tree, guessing the height and history.

Back inside, the children will have the opportunity to grow an oak tree from an acorn, in a recycled milk carton, and watch it grow.

Sharon Labchuk is a longtime environmental activist and part-time organic beekeeper from Prince Edward Island. She has twice run for a seat in Ottawa’s House of Commons, making strong showings around 5% for Canada’s fledgling Green Party. She is also leader of the provincial wing of her party. In a widely circulated email, she wrote:

“I’m on an organic beekeeping list of about 1,000 people, mostly Americans, and no one in the organic beekeeping world, including commercial beekeepers, is reporting colony collapse on this list. The problem with the big commercial guys is that they put pesticides in their hives to fumigate for varroa mites, and they feed antibiotics to the bees.

They also haul the hives by truck all over the place to make more money with pollination services, which stresses the colonies.”

Her email recommends a visit to the Bush Bees Web site, where Michael Bush felt compelled to put a message to the beekeeping world right on the top page:

“Most of us beekeepers are fighting with the Varroa mites.

I’m happy to say my biggest problems are things like trying to get nucs through the winter and coming up with hives that won’t hurt my back from lifting or better ways to feed the bees.

This change from fighting the mites is mostly because I’ve gone to natural sized cells. In case you weren’t aware, and I wasn’t for a long time, the foundation in common usage results in much larger bees than what you would find in a natural hive. I’ve measured sections of natural worker brood comb that are 4.6mm in diameter. What most people use for worker brood is foundation that is 5.4mm in diameter.

If you translate that into three dimensions instead of one, it produces a bee that is about half as large again as is natural. By letting the bees build natural sized cells, I have virtually eliminated my Varroa and Tracheal mite problems. One cause of this is shorter capping times by one day, and shorter post-capping times by one day. This means less Varroa get into the cells, and less Varroa reproduce in the cells.

Who should be surprised that the major media reports forget to tell us that the dying bees are actually hyper-bred varieties that we coax into a larger than normal body size?

It sounds just like the beef industry. And, have we here a solution to the vanishing bee problem? Is it one that the CCD Working Group, or indeed, the scientific world at large, will support? Will media coverage affect government action in dealing with this issue?”

These are important questions to ask. It is not an uncommonly held opinion that, although this new pattern of bee colony collapse seems to have struck from out of the blue (which suggests a triggering agent), it is likely that some biological limit in the bees has been crossed. There is no shortage of evidence that we have been fast approaching this limit for some time.

We’ve been pushing them too hard, Dr. Peter Kevan, an associate professor of environmental biology at the University of Guelph in Ontario, told the CBC. And we’re starving them out by feeding them artificially and moving them great distances. Given the stress commercial bees are under, Kevan suggests CCD might be caused by parasitic mites, or long cold winters, or long wet springs, or pesticides, or genetically modified crops. Maybe it’s all of the above…