Food waste for fuel in London and beyond...

I had an early start to get to London for the start of a workship on AD - anaerobic digestion. It might be a bit weird but it's a subject I'm rather passionate about. AD is essentially like composting in an enclosed system. It can be used to treat food waste, farm waste, sewage sludge and pretty well anything that's slushy and compostable.

At the end of the process you get biogas, which can be used to generate electricity, heat boilers or as a vehicle fuel. And the remaining sludge left at the bottom is an excellent fertiliser - replacing energy-intensive agri-chemicals.

In 2006, when I was researching The New Green Consumer Guide, I realised that AD had huge potential but was barely being used. At the end of the year I organised a conference with South Somerset District Council called 'Biogas - Explosive Potential'. Amazingly the conference hall was full to bursting as interest in the issue was just getting going.

Back to the London event. Organised by BiogenGreenfinch, who describe themselves as a company pioneering food waste recycling for biofertiliser and renewable energy. The workshop entitled AD in the City - solving the urban food waste challenge was aimed at London councils encouraging them to use AD.

They appeared to be pretty keen on the idea. Ealing Council signed up with BiogenGreenfinch last year, for 5,000 tonnes of food waste but this is a very small proportion of the 2.5 million tonnes apparently produced by Londoners - and that's only domestic food waste. Two other West London boroughs have just signed up - Richmond and Hounslow - and Hammersmith & Fulham look like they'll be joining the fray. And following the workshop, other councils are apparently queuing up to have a look at whether it might work for them.

The London Councils are being encouraged by the London Waste and Recycling Board. This body was set last year to boost recycling - and is chaired by the London Mayor - Boris Johnson. They said that food waste in London is contributing about 210,000 tonnes of CO2 to the atmosphere each year.

I don't think much food was wasted from the lunch served at the end of the workshop. Cooked by Oliver Rowe, who runs a restaurant near Kings Cross called Konstam, it was delicious. The unsual feature of the restaurant is that it sources 85% of its ingredients from within the M25. this means using apple balsamic vinegar, rape seed oil, rosehips, nettles, ground elder and wild garlic. It also means that the menu is very seasonal. We were served the most appetising pork with crunchy crackling and rhubarb sauce, served on a bed of lettuce with roast potatoes.

Cycling to school

This photo was taken in 2007 - not on the way to school...

It's brilliant. I've started cycling to my son's school in the morning - and back. Rollo and Monty got me going. They decided that they wanted to run to school along the lanes. I was rather surprised to see how far they got - 2 miles on the first day and 3.5 on the second when I had got them to put on their trainers.

The enthusiasm for being fit was contagious. Rather than following after them in the car - and picking them up for the final leg of the journey, I thought I'd try cycling. We got the bikes fixed and set out on Monday morning, only a little ahead of our normal departure time. It's 4.5 miles and took us about half an hour. I think Monty, who was with me, could do it a bit faster but he had to wait for me at the top of the hills!

I thought that the return journey would be the problem. Actually, quite the opposite. I could take a more leisurely pace, look at the view and smell the scents as I rode by. Lilac and May trees are at their peak.

Back in my office by 9am I am feeling fitter and healthier. I just hope we can keep it up - when the weather isn't quite so nice I suspect I won't be quite so keen. This morning it was very cold to start with, so tomorrow I'm going to find some gloves....

My Garden

It's such a wonderful time of year for getting into the garden. I've actually managed to mow the lawn - I'm afraid that I didn't use a scythe. I've also been pruning the apples trees - and getting rid of the ivy that's wrapping itself around them and planting vegetables.

Home-grown food is a real treat. Apart from an abundance of apples, which come regardless as to how much attention I give them, the rest of my produce was a little thin last year. Only enough tomatoes for an odd sweet mouthful. Cabbages, cauliflowers and purple sprouting that withered on their storks. And squashes that never materialised. Although I did have success with my globe artichokes.

I realised that what was needed was nutrients. The farmer next door gave me a whole heap of cow manure, which has now been dug in and planted with seed potatoes. My compost from food waste doesn't look ready for spreading, so I went to B&Q to see if I could get some nice crumbly stuff for planting the other vegetable seeds.

I was rather disappointed to see that they were still selling products containing peat, albeit with a message saying that the peat had come from sustainable sources. I still don't think it's a good thing. Monty Don's comment about peat just about sums it up "Digging it up is like ripping out ancient hedgerows just to make sawdust". B&Q didn't stock compost made by the council from household food and garden waste, so I didn't buy it from them.

Another problem I have is weeds. One patch has been completely over-taken by nettles, dockleaves and buttercups. The gardener who came to help with some digging suggested that I spray it with Roundup. I'm afraid not - my garden is organic. Neither was I very enthusiastic about the recommendation to use slug pellets - I've got a jar of broken egg shells I'm going to try out to deter these pests. Or maybe I'll go slug hunting at dusk.

Rabbits too like to eat my vegetables. Luckily there are two fearsome rabbit predators around - my cat, who likes to leave their remains around the house, and the farmer next door who shoots them and gives them to me for the pot.

This year, I'm hopeful there will be an abundance of vegetables, so my artichokes won't be the only treat.

Regifting - eek

A rather well-wrapped present...

I don't just recycled my rubbish, I recycle presents too. I've recently discovered that this is called 'regifting'. Apparently this is an American phrase and I learnt it from my sister-in-law, who comes from the state of Washington but is now living in Devon.

If I get a present that I don't think I'm going to use I put it in my a large Ottoman box in the spare room. This also applies to presents given to the children. If they don't look that interested or I think they're going to tear through the wrapping and then lose interest in seconds, I seize the gift and store it away.

The present box, boosted by things I have bought too, is then a brilliant resource for birthdays throughout the year. Wrapping paper too is used again - the Sellotape carefully removed and names cut out.

Recycling presents and wrapping paper is good from a green point of view. Clearly it makes sense to pass things on if you're not going to make the most of them. However, there are pitfalls and I've recently experienced one.

Thinking about a suitable present for my 6-year old nephew, I found a remote controlled car still in its box. It seemed particularly appropriate because it required a bit of adult help in putting it together - and my brother (his father) is an engineer and so well qualified for that.

Luckily we arrived with a few presents - some from my children, as well as one from me... Oh dear. My sister-in-law exclaimed when she saw the car "It's a regift!". And she had given it to one of my children for Christmas. Huge embarrassment. Luckily, she saw the funny side. She said that she'd be able to dine out on the story for a little while.

This experience hasn't deterred me from 'regifting' but it will make me more careful to make a note of who has given me what. And, my nephew didn't seem to mind a bit - he was delighted with the car!

Haller transformation

Below is an article I wrote for Telegraph website about millipedes, hippos and Haller in Kenya. I'm a trustee of Haller - a charity, I co-founded that supports sustainable living in Kenya. In March I spent a week just North of Mombasa looking at how things have progressed since my last visit over four years ago. The article gives an idea of how Haller started and some of the projects that are now happening on the ground.

Millipedes and eco-systems

Look around at the lush and fertile landscape and it's hard to believe that this is a man-made environment. Yellow weaver birds making a huge din whilst building their pendulous nests, a sleek cormorant prepares to dive into the water and even a hippo wallows in the mud.

The hippo as it turns out has a vital role to play in the ecosystem. The mud on it's back is removed from the ponds and so stops the water hole from silting up. The crocodiles too play their part. They feed on the dead farm animals or remnants from the thriving organic fish-farm. And their excreta helps fertilise the water making the algae grow, which is food for the fish as well as nutrients for the rice paddies and bananas.

Only 30 years ago – this thriving forest landscape was a rocky, lunar-like desert, created by mining coral for cement. Actually, there are still parts of it which have been newly quarried to give one an idea of how it all started. The inspiration behind the transformation is Dr. Rene Haller, a Swiss agronomist, who has just celebrated his 50th anniversary of living on the Kenyan Coast.

In 1959 he came to work at the Bamburi Cement Factory – growing fruit and vegetables for the workers. But Haller didn't stop there. He started experimenting with different trees to see if any would put down roots into the dry, rocky terrain. The Casuarina tree, whose seeds had been washed onto Kenyan shores when Krakatoa erupted in the 1860s, was the best candidate. It produces nutrients in nodules on its roots and so is self-sustaining.

But Haller's most miraculous discovery was the beneficial effects of the millipede. This marvellous red-legged insect loves eating the needles dropped by the casuarinas. It's pooh then becomes the humus for the more vegetation – thus starting the whole ecosystem development.

Haller's vision didn't stop there. He managed to set up lots of different business enterprises supported by rehabilitated land, both employing and providing food for hundreds of local people. He also managed to demonstrate the value of conservation – for example, by showing farmers the benefits of tree-planting in preserving water for irrigation.

An inspiring man, Haller has managed to get worldwide interest in his ideas. The most exciting of which is a charity named after him – Haller – which is promoting his ideas in the poverty-stricken rural communities close to the quarry.

An example of the holistic thinking applied by Haller, the organisation, has been used in dam building projects. To prevent the fresh water pools becoming breeding grounds for mosquitoes, they have introduced fish, which eat the mosquito larvae. The fish are also a rich source of protein for the community and they fertilise the water, which makes it even better for feeding the crops. Also, any surplus fish can be sold, providing much needed income for the community.

If you run through the forest trails, that now criss-cross the rehabilitated quarry land near Mombasa, you're very likely to crush a shiny black millipede – or a mating pair – under foot. But you should avoid them if you can. They continue convert the forest floor into rich humus unaware of the pivotal role they've played in greening the cement quarry – and now helping the local people out of poverty.

Rene Haller often says 'seeing is believing' – he doesn't just tell people how to do something, he shows them. If you find yourself near Mombasa, go to Haller Park and have a look. If you're not planning to be there you might be inspired by looking at the Haller website.