Compost toilets, walls made from straw bales and rammed earth blocks, wind turbines to generate electricity, rain harvesters to save water, sun pipes to bring natural light into dark areas and save plugging in a lamp.

almost everything anyone's ever thought of to help save precious resources will be centre stage at an exhibition in Wycombe which began on Saturday.

Many of the companies at the Building for the Future event at the Environment Centre, at Holywell Mead, on the Rye, will be local firms renowned in their field for helping to reduce the harmful effects of modern life.

An environmental group Low-Impact Living Initiative based near Winslow will be staging a green roadshow at the site on Saturday and Sunday.

They run courses, produce books and can put you in touch with suppliers who know everything there is to know about home-made bio-diesel, compost loos, keeping poultry, natural cleaners, rammed earth construction, straw-bale building, solar panels, even using vegetable oil as fuel for cars.

Pop down to the exhibition at the weekend entrance is free and you can see one of their dual fuel vehicles.

Companies who will be exhibiting through to the end of the show on November 6 include Monodraught, based on the Cressex Business Park. Professor Terry Payne and his team are world leaders in the distribution of sun pipes. Their latest innovation is a fully-integrated bathroom light/ ventilation kit called the Solavent, incorporating a sun pipe, solar driven fan and two low voltage halogen lights in one unit.

The company is also helping to produce roof wind turbines and photovoltaic tiles ("like having a power station on your roof", as one techie said) to generate electricity.

Renewable energy exponents TV Energy of Newbury the Thames Valley Energy Management Agency responsible for spreading the gospel in Bucks, Berks and Oxon, has already fitted a wind turbine on the roof of Carrington Junior School in Flackwell Heath and a solar water system for the swimming pool.

The agency is currently working on a revolutionary system using 50 per cent gas and 50 per cent woodchip to provide heating and power for Bracknell town centre.

Heat pumps that extract heat from the ground to provide central heating and hot water will be demonstrated by the Oxfordshire firm Icenergy. "In the summer months the process can be reversed to cool buildings," explains company spokesman Andrew Sheldon.

Another local exhibitor will be Challis Water Controls of Cookham, the UK distributor for a Scandinavian shower mixer kit intended for large scale commercial and leisure users. "It saves 50-70 per cent of water and energy with no loss of performance," claims Chris Challis.

With water prices set to increase by an average of 18 per cent over the next few years, there should be lots of interest in a display by UK Rainharvesting Systems showing how rain can be used for loos, washing machines and gardens.

One of the best known wholesalers of natural building materials, Neil May of Natural Building Technologies from Oakley, will be displaying his range of lime-based paints, natural insulation materials, plasters, renders and construction blocks.

He leads the way in getting the message across to housebuilders and developers that natural materials and natural construction methods give the best results and, properly executed, cost no more than the commonly used mass-produced alternative.

Meanwhile, Wycombe Wildlife Group will demonstrate how gardens can be planted to attract butterflies and bees and the countryside can look like it did before chemicals became king.

Lesley Stoner, Wycombe Council's dedicated environmental co-ordinator sums up: "There's so much talent in this area, so many firms with innovative ideas.

"We hope this exhibition will give them a showcase to demonstrate that getting back to basics is the best way forward."