Peter Harper is a biologist, gardener and landscape designer who has worked at the Centre of Alternative Technology (CAT), possibly Europe's best known eco-centre, since 1983.

Successes
The things that have gone well for CAT over the last 20 years. Second, the things that have not gone so well. Third, the lessons we have learned, or where we have changed our minds, and fourth, some suggestions for future directions.

• Renewable energy: about 90% of our electricity is from wind, water and sun, and its more reliable than the local public supply, to which we are not connected.
• Ecological building: all the materials are chosen with environmental criteria in mind, and the life-cycle energy consumption of our latest buildings is about 10% of the typical levels.
• Biological wastes: we treat all solid and liquid wastes, converting them into compost and clean water. 90% of the nutrients are recovered.
• Ecological land use: we use no agrochemicals, and take care to build habitat diversity into all new developments. Plants of all kinds flourish, and more and more animals turn up each year, including rare species such as red kites, otters and dormice.

All this is fairly standard technical stuff, and relatively easy. What about the organisational side?

• The structure is not fixed, but has evolved continuously, seeking a balance between democracy and efficiency.
• It is a worker's co-operative, owned and managed by its staff of about 30.
• All are paid equally.
• Management is largely decentralised, but with an elected co-ordinating group.
• Most decisions are by consensus, with provision for voting if absolutely necessary: this has only been invoked twice.

These features are quite common in alternative organisations, although rare in the mainstream world. But it is of little value Being Green in isolation: the ideas and practices need to be amplified a hundred, a thousandfold. The ideas must get out into the world and propagate themselves. At the same time an ecovillage must be economically self-supporting.

One of the most important things we have done at CAT is to develop activities which simultaneously get the message across and provide an income. These include a visitor demonstration centre with 80,000 day visitors a year; innovative residential courses in green subjects for up to 40 people at a time, ranging in level from young children to professionals; an information and consultancy service; and publications, with up to 50 new titles a year.

The operation has survived, grown, spawned several independent enterprises, and has an annual turnover of more than 1 million sterling. Success? Yes, but let us turn quickly to something far more interesting: failure. Can you recognise your own organisation in any of what follows?

There is an important role for eco-villages here as test beds, precisely because they are not afraid of life-style changes.

Failures

In spite of our avowed purpose and our green rhetoric, we have failed to make a very careful eco-audit of everything we do. We cannot put our hands on our hearts in every case and say "Yes, this method or technique is an environmental improvement, a clear step towards sustainability."

• Transport: not very good at all. Lots of cars. It's a rural area and people tend to use cars rather than bikes or public transport.
• Communal life: has declined. Only a minority of staff now live on the site, and currently only one child. There is little interest in classical communitarianism. We have not integrated very well with the local population. Our 'universal' perspective means we tend to ignore local matters.
• Finances and fundraising: we always seem to be broke. Still here, but it's always a struggle.
• Maintenance: the place always looks a bit scruffy. By temperament we tend to be creators, starters - not maintainers. That's a tough one.
• People care: individually there's a lot of solidarity and affection, but we haven't institutionalised it very well.
• The spiritual dimension: well, thinking about the much vaunted three-legged stool representing the balance of ecological, social and spiritual aspects, all I can say is that we're not bad on ecology.

What have we learned, or how has our perspective changed over the years?

When you first start off in these experimental fields you have very little idea of what is going to work and what will not. Well, by now we have sorted out a lot of the wheat from the chaff and can give helpful lists identifying the good, the bad and the maybe. Some eco-techniques that look irresistible on paper turn out to be lemons.

We take a much longer view now. In the early seventies I remember thinking that we had perhaps five or ten years to Save the Planet. We were in such a panic! Well, twenty years later things remain urgent but we realise they cannot be changed overnight. Now we're thinking it terms of fifty or hundred years.

We have accepted that we are modern people. We have to somehow achieve 'sustainability' but we do not want to be peasants and there will be no 'going back'. Sure we love elegant, simple solutions where you achieve a lot with a little, but we are not embarrassed by industrial high-tech if it does what we want. Once upon a time we thought the future lay in a sophisticated kind of neo-primitivism. Some still do, we don't.

We recognise now that collective, shared, large-scale systems are sometimes the right solutions and give the best ecological answers. Small is not always beautiful. It may well be the first thing to try, but don't apply it dogmatically.

We also accept that most of the action is going to be in the cities, where most people will be living. Farming, as always, will have its part to play, but will not figure prominently in most people's lives.

Once we thought that modern society was terminally corrupt and we should have nothing to do with it; that we should be a self-sufficient as possible. Now we see ourselves as inevitably part of British and global society and want to participate in and change it. We have moved from withdrawal to engagement.

There is no substitute for numerical accuracy. The modern world is so bizarre that if you don't make at least some attempt to measure what you are doing you can easily make awful mistakes and be out by a factor of 100 without noticing it, leading to years of wasted effort. You must do the numbers.

We have learned that reality does not necessarily speak for itself. At the beginning we thought people would come along and look at our work and say, "Wow! That's Fantastic! I'm going to do it too." No. They don't. Somehow they don't see it in the right way, or in some cases don't notice it at all. Ideas, principles, structures, equipment all have to be presented in the right way to command attention and understanding. Suddenly we find we are in showbiz; presentation and communication may demand more of our time and effort than actual content.

Rotation of tasks, once thought to be essential to the development of each individual and their relationship with the organisation, has only a minor importance. Skills are precious and take time to develop; they need conserving and feeding with training and long experience.

Originally it was thought that consensus-based decision making by the whole group was good because it was maximally democratic. But its inefficiency soon becomes tiresome, and now we happily accept the existence of an elected management team to deal with general and interdepartmental issues.

In earlier days we thought we had all the answers. Now we know that this is pathetically false, and that we must play our part in the wider movement. It is useful therefore to have maps of the whole movement, the better to know where our most useful contributions may lie.

Peter Harper's Guide to Greenery...
COOL! Where can I get some? (Eco-chic)	ALL RIGHT if I must. (Light Greens)	ER…would rather not, thanks. (Gung-ho Greens)	YOU MUST BE JOKING! (Neolithic Green)
Email	Low energy light bulbs	Using public transport	Secondhand clothes
"Body Shop" products	Sorting domestic solid waste	Job-sharing	Composting toilets
Super-insulated houses	Re-using envelopes	Biking to work	Thermal underwear
Lead free petrol	Eco-friendly washing products	Car pooling	No freezer
Lightweight, 200 mpg cars	"White cars"	Home composting	No fridge
Miniaturisation	Laundry services	Wholefoods	Not buying much
Hydrogen fuel	Water meters	Clothes from recycled yarns	Local diet
Amazing glazing	Solar water heating	Insulated shutters	No air travel
		Bikes with electric boost	No car
			Cold showers

Where are we going next?

How should we apply some of the knowledge and insights that we have collected?

The basic problem is one of sustainability, but this is a notoriously vague term and it would be nice to put some numbers into it.

Our provisional understanding is that it will require something like an 80% reduction in the throughput of energy and materials for European countries - more for North America. This sounds fairly drastic, but it seems we are stuck with something of the kind. What to do? It is noticeable that some positive measures (such as more efficient car engines) are popular, parallel with the grain of mainstream culture and are easy to sell, while others (such as not using cars at all) are not. So the 'take up' of popular measures will be rapid and could be multiplied by millions of times, while the unpopular measures will be largely ignored. But it is also noticeable that the popular measures tend to offer only a marginal improvement in environmental impact, while many of the unpopular ones, if widely adopted, could offer a very rapid progress towards our target.

There is a dilemma here, and we have tried to analyze it a bit more systematically to see whether we can pick out the 'cherries' - items that are both environmentally powerful and potentially acceptable to mainstream society, perhaps with a bit of technical development and institutional support. At the same time we could perhaps spit out some 'pips' - items which don't make much difference and nobody wants to do anyway.

An example of this 'cherry picking': In order to reduce household waste by 80% you start with fewer and more discriminating purchases (not very popular, but not repulsive, and could be encouraged). Once the stuff is in the house you obviously have to separate out the solid recyclables: cans, bottles, newspaper. This is typically around 40% of the total, is popular, is encouraged from on high and widely practised. Most of the rest is kitchen and garden waste, packaging paper and card, and plastics.

Householders can't do a great deal with plastics themselves; although they have a bad environmental image in a landfill they squash down to less than 10% and they take some CO2 with them. So let them go: they are a 'pip'. The rest is relatively easy to compost, and home-composting is in one of the intermediate-popularity categories: promising! Local authorities don't like organic waste because in bulk it smells and causes all sorts of health problems, so generally they will encourage householders to compost it: this is even more promising.

As well as environmentalists wanting to remove them as potential pollutants, gardeners are going to be interested in the plant nutrients (nitrogen, phosphorus, potash, etc.) contained in household organic wastes, because if reclaimed they could save the cost of fertilisers and soil improvers. If we rank all the household organic wastes, including the liquid ones, in order their nutrient content we get:

• Kitchen waste
• Garden wastes
• Urine
• Faeces
• Grey water
• Paper and card

It is encouraging that the two richest items are also ones that are familiar and easy to handle. This is a potential cherry. It is noticeable also that of the liquid wastes the one which is free of pathogens and easiest to collect is also the richest in nutrients: another potential cherry here? In fact if we add the first three together we have got 95% of the nutrients flow through the house: the rest of the liquid wastes - hard to collect and very much against the grain of popular taste! - we can reject as 'pips'. Notice here the important part played by 'doing the numbers'.

The biological difficulty in releasing the promise of these potential cherries is that the three clean wastes are far too rich: in order to be composted effectively they need to be combined with a bulky, fibrous material poor in nutrients but rich in carbon. But - another cherry coming up - this is just what we have at the end of the list, readily available and very easy to collect, which most paper banks will not take, and which occupy huge volumes in landfill: packaging card and miscellaneous waste paper.

It turns out that paper and card compost extremely well. In fact they considerably improve the quality and quantity of ordinary domestic compost. You can also combine urine and cardboard effectively and the composted product is indistinguishable from fine soil.

Picking cherries and spitting out the pips is a preliminary process. Then you go on to designing the hardware, securing the institutional support, stitching up coalitions of interested parties, training, informational campaigns and so on. It is rarely just a simple piece of hardware, but a complex mixture of technique and lifestyle.

There is an important role for eco-villages here as test beds, precisely because they are not afraid of life-style changes. They can try things out, make improvements, get the bugs out. They should be the laboratories of techno-social innovation in the field of sustainability. Their very diversity is a strength because they can sample many different styles and standards of living. The wealthier, bourgeois communities will be more in tune with mainstream western culture, and the radical, low-cost Bohemian communities could develop stronger cherries with longer-term potential and wider global application. Something for everyone!

Peter Harper
Centre for Alternative Technology
Wales, UK