It seems that in all the hot air about climate change, there has been a lot of talk about green thinking, and not enough thinking about being green. But one man who has thought about it more than most is architect Alastair Binnie. In fact, he has built a business out of how to make buildings as sustainable environmentally and, critically, economically as possible.

Oxford-based Alastair Binnie Architecture and Environment was founded 18 years ago by Mr Binnie, who had been working for a commercial practise in London. Even then his ethos was to produce buildings that were as environmentally-friendly as possible.

As time went on, Mr Binnie and his team became increasingly sophisticated at calculating the energy use of buildings and a system called Oxford Energy X (OEX) was developed.

This was based on a German standard and produces a report tailored to an individual property, its surroundings, prevailing weather conditions and the particular needs of its occupier. The idea is to produce a report recommending the optimum use of energy for that particular building.

Mr Binnie, 49, explained: “It is very specific. I have to set up a user picture of the building 24 hours a day to ensure the most cost-effective technology is employed.

“I also look at the physical properties of materials and the performance of building services.”

A lot of the ideas come from the Passivhaus Institute in Germany, which is not so much interested in reducing the effects of climate change as producing economically-efficient buildings. Of course, the two go hand-in-hand.

One of Mr Binnie’s most recent projects was a property in Southmoor Road, Oxford, which took three years to complete and was a very personal project for owners Professor Rory Collins and partner Julie Elliott.

Mr Binnie explained: “They came to us because they knew our environmental leanings. They had ideas and it was up to us to translate them into a workable design.”

Like all Mr Binnie’s projects, he made as much use of natural light and what he terms “solar gain” as possible.

While the exterior of the handsome Victorian property was not changed radically, save the large windows on the rear, internally major works were carried out, such as moving the staircase back to allow more light in, replacing the roof and heavily insulating the entire house.

But for all his keenness on the power of the sun, Mr Binnie decided against solar panels.

“The roof did not have a south-facing slope — it needs to be somewhere between south-east and south-west to make solar panels economically viable.”

Mr Binnie’s first major project was a village hall in the village of Northmoor built on behalf of the Northmoor Trust.

“We wanted to look at ways of building sustainably and also offering very low running costs while using local materials.”

Incorporated into the construction was a “thermal store” comprising clear blocks which are heated by the sun that is slowly released over the course of up to a week, and forming part of a warm air heating system.

Bearing in mind the building was not constantly occupied, it could be heated quickly, making it an ideal system for its specific use. The building was monitored for two years by experts from University College London, from which Mr Binnie learned a lot.

Further projects included a visitors’ centre for a science project on the island of Rodrigues in the Indian Ocean, as well as schemes in France and Italy, before another community centre in Marcham built offering zero carbon emissions.

Another challenging project was a development of 11 houses in the village of Colonsay in the Hebrides. Sections of the homes were shipped out and weather data was analysed. Again outlay on expensive “green” devices was kept to a minimum.

“It is cheaper to reduce the energy demand of a building through high levels of insulation and a sensible approach to glazing, so it does not overheat in summer and does not lose too much in winter,” said Mr Binnie.

The common sense approach includes limiting cold passages and keeping rooms air-tight with the use of mechanical ventilation systems and heat recovery.

“It takes the heat out of the outgoing air and puts it into the incoming air,” Mr Binnie explained.

Now he finds demand for his practical approach growing as building legislation and public awareness has caught up.

“When we started, we were almost environmental campaigners and had to convince people of the benefits of building in an environmentally-friendly way.

“Now people come to us knowing what they want to achieve, but not necessarily how they can achieve it.”

Despite Mr Binney’s no nonsense ethos, he admits it is still more expensive to follow the green route into building design, particularly when chasing the holy grail of zero carbon emissions.

But in the long term he argues that reducing the energy demands of a building is cheaper.

And when it comes to technology, Mr Binnie advocates wind over photovoltaic cells, and is critical of local government’s reluctance to approve plans for wind turbines.

“There is still a lot of negativity about wind, despite the the country being littered with windmills 200 years ago.”

Understandably, the practice has won plaudits including the Observer Ethical Award for an ordinary house in St Leonard’s Road, Headington, where energy use was cut by a remarkable 79 per cent. The complete renovation of the property cost £100,000.

Of course, Mr Binnie’s approach is still evolving but the pioneering practice remains at the forefront of sustainable building design.

But at its core is a very simple approach.

He said: “If you reduce energy demand, then you only need a boiler that is half the size.”

And it doesn’t take an economist to work out the benefits of that.

Name: Alastair Binnie Architecture and Environment Established: 1982 Managing director: Alastair Binnie Number of staff: Eight Annual turnover: £300,000 Contact: 01865 554558 Web: www.ab-arch.co.uk