Pier-munching gribble may provide breakthrough for biofuels

A wood-boring crustacean that spends much of its time munching through the wooden supports that hold up piers could help provide the next breakthrough in green energy. The gribble uses enzymes in its gut to break down wood and scientists want to employ it to produce climate-friendly biofuels from natural products such as willow and straw.

The work will form part of a £27m project to make second-generation biofuels a commercial reality within 10 years. The new biofuels would not lead to a net release of carbon dioxide but also won't compete with land for edible crops. The money will come from the government-backed Biotechnology and Biological Sciences Research Council (BBSRC) and a coalition of 15 industrial partners including BP and Ceres.

The cash is aimed at funding research to use plants more efficiently as fuel. The cell walls of plants are made of a complex sugar called cellulose, which is usually mixed with a polymer called lignin. Second-generation biofuels are made by breaking down the cellulose and fermenting it to produce fuels such as ethanol or butanol.

One of the major challenges for biologists is to find chemical enzymes that can efficiently break down cell walls which contain cellulose and lignin. The gribble, a tiny shrimp-like crustacean, seems particularly good at this task. "It's single-handedly responsible for gnawing away at several piers on our south coast and, within its intestinal tract, are enzymes that can unlock some of the polymers [in wood-based materials]," said Professor Katherine Smart, a plant scientist at University of Nottingham and one of the leaders of the project.

First generation biofuels are made from crops that store sugars and starches in their grains. "This has two main problems – it diverts away from the food chain but also it's very energy intensive to grow the crops," said Dr Angela Karp of Rothamsted Research. "You have to grow them every year and it requires a lot of nitrogen fertilisers to grow those grains."

Instead, the BBSRC money will be concentrated on waste materials from normal food crops – wheat straw, spent grain – and also plants that are not grown for food production but still produce a large amount of biomass quickly, such as willows and grasses

Smart said there was much to be done in improving the efficiency in extracting a plant's cellulose and then converting it into alcohol. "At the moment we can produce 19g of ethanol from 100g of straw. Based on the current amount of straw not used currently that means we have between 8-10bn tonnes of straw available in the UK for this kind of conversion. That could produce about a 10% of current use of petrol."

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Britain's first council house made out of... straw

Britain's first council houses made out of straw are to be built in a bid to cut costs and energy consumption.
The six semi-detached homes will be built from 500 bales but will be indistinguishable from normal homes because of their lime-washed walls.
At £60,000, the three-bed properties will cost £20,000 less to build than a conventional house.

They are being built as an 'experiment' by North Kesteven County Council, Lincs., to cut construction costs and meet energy consumption targets.
Marion Brighton, leader of the council, said straw with its exceptional heating properties had massive potential.
She said: 'It's all about affordability, sustainability and cutting down energy consumption. It's the first time it has ever been tried in the UK.
'The straw houses tick all the boxes - cost and energy efficiency. Also, we have a lot of straw in the area. It makes sense to make use of it.
'The properties will look similar to conventional council properties except the outer walls will be whitewashed with lime rather than red brick.
'We hope to continue building with straw and to encourage other councils to follow suit.'
Two semi-detached units each containing two three bed properties are due to be built in the village of Martin, Lincs., in April.
Construction of a further one semi-detached unit is set to start later in the year in Waddington, Lincs.
A spokeswoman for architects Amazon Nails, Todmorden, York., said household bills for the straw homes, said to have a lifespan of 100 years, will be low.
The houses will be on the National Grid but gas would only be supplied for cooking.
The straw walls will be airtight and superinsulated and natural light will be used to maximise warmth.
Each property will have a wood burning stove for the very coldest winter spells.


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How green are wood-burning fires?

It is hardly a secret: heating our house gives each of us a stonking great carbon footprint, what with domestic homes accounting for a quarter of the UK's total energy use. So what have the finely tuned, technologically thrusting innovators of this generation come up with by way of a low-carbon, renewable solution? Er, burning stuff in a fire, pretty much in the manner of our Victorian forefathers.

What this idea may lack in futuristic ingenuity it makes up for in increasing popularity. Householders are embracing open fires (not literally, which would be dangerous) and wood-burning stoves as a means of being greener, cheaper and feeling more secure about their fuel supply. Sales for wood-burning stoves are reported to be up by 40% on last year in the UK.

From an ethical standpoint we can a) be thankful that there's no longer a child-labour issue involved with today's chimney sweeps and b) celebrate the fact that new wood-burning stoves operate at around 75% efficiency (a traditional fireplace is just 10-20% efficient). According to the industry group www.stovesandchimneys.co.uk, an open fire requires four logs for every one put in a wood burner.

However, bear in mind that when it comes to air pollution, a problem shared is still very much a problem. There is a distinct lack of consensus when it comes to air-quality management and domestic fires, but even the newest wood burners kick out particulate matter (tiny, easily absorbed particles, considered possible carcinogens and more readily associated with traffic pollution). Recently, Swedish researchers concluded that levels of polycyclic aromatic hydrocarbons (chemical compounds, some of which have been identified as carcinogenic) were five times higher in homes with wood-burning appliances than those without. Proponents, meanwhile, argue that wood is cleaner than coal and oil, emitting no sulphur dioxide and destroying dioxins through heat.


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Thermostat on low? The pipes are calling

Insurers are counting the cost of some of the coldest winter weather in a decade, with claims for burst pipes and tanks running at double the levels of last year. Families who have turned the thermostat down too low while away on a Christmas break have returned to homes wrecked by mains-pressure water pouring through ceilings and floors for days.

Many households are unaware just how high thermostats need to be to prevent freezing pipes. Halifax  recommends central heating is set at a minimum of 10 degrees.

Some modern boilers have a frost protection thermostat which turns on automatically if the temperature drops to a level that causes pipes to freeze.

Paradoxically, homes with proper loft insulation may be more at risk, as the heat from downstairs fails to penetrate upwards. A Norwich Union spokeswoman says: "Remember to remove the hatch to your loft so that warm air can circulate. This may appear environmentally unfriendly, or a little extravagant but it might mean the difference between a ruined home or a dry one when you return after a break."

Sainsbury's home insurance estimates that since 22 December, the UK insurance industry has received more than 13,000 home insurance claims linked to water damage under the category of "forcible/violent bursting", and it says the freezing weather has contributed to this.

It estimates the value of these claims is already close to £30m. Neil Laird, Sainsbury's home insurance manager, says: "There have certainly been more claims linked to water damage in recent weeks than we'd expect to see when the weather is milder. Temperatures have dropped to as low as -10C, and, with more cold weather predicted, we expect to see more claims linked to water damage.

• Insulate your pipes with preformed insulation, and replace the washers on any dripping taps - if the taps freeze, the pipe will get blocked.

• Know where your water valves are, and learn how to shut them off in case a pipe does burst.

• In very cold weather the heating will need to be on low, or set to come on a couple of times a day, especially if you're going away.

• Open the loft trapdoor on cold days to let heat in.

And do check your level of buildings and contents cover. Note, if you are away from your property on an extended break - typically more than 45 to 60 days - there is the risk your policy may not pay out.

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