Clean Break – UK

July 2004

Glass is taken for granted. On average, every family in the UK disposes of around 500 glass bottles and jars a year, equating to about 2 million tonnes of used glass. Just 35 per cent of this was recycled in the UK in 2001.The disposal of glass poses a serious environmental problem, and the UK is lagging in the field of recycling ideas and practices. A company called Green Glass, however, has developed a system of glass recycling that is cheap, energy efficient, and effective. The system has also helped two South African entrepreneurs escape from the jaws of poverty.

Wasteful World

‘Everything we use to communicate, move, stay warm, stay cool, sit, sleep, cook, and refrigerate comes from the 15 billion tonnes of raw material that humans extract from the Earth each year.’

(Emel, Bridge and Kruger, 2003:377)

Modern living has brought an increased spatial separation of production from consumption. This obscures the socio-political, economic and environmental processes through which production and consumption occur, leading to a lack of public awareness of such processes. This problem is apparent in the developed world and particularly in the UK, which holds among the lowest proportions of recycling in Europe – the European average is about 55 per cent, with Switzerland recycling about 95 per cent. In the UK there is a lack of public awareness of the need for and possibilities of recycling.

Bulging at the Seams

The UK produces more than 430 million tonnes of rubbish per year, with households contributing over 25 million tonnes. Household waste causes a problem due to its cumulative nature; the amount produced from homes is said to increase at a rate of 3-5 per cent per year. By 2020, therefore, the volume of waste produced in the UK is expected to have doubled. Therefore, the question being asked by many environmental organisations is: what will happen to the growing volumes of waste in the long term?

The UK will need 2,300 new waste treatment facilities by 2020 if it is to avoid a major crisis involving millions of tonnes of untreated waste. While household rubbish makes up only 8 per cent of the UK’s total volume of waste, it is such waste that is attracting the most attention. The cheap disposal option of landfill is not a long-term option due to land availability and EU regulation. The Institute of Civil Engineers, in their State of the Nation report of 2004, has therefore called for a change in public consciousness towards waste disposal.

'Unprocessed Waste': Theo Schilderman
‘Unprocessed Waste’: Theo Schilderman

The first ‘crunch point’ will come in 2010, when the first target for reducing the amount of waste going into landfill comes into force. It takes at least five years for a new waste facility to be created and start functioning. The public’s adverse attitudes towards new waste facilities opening close to their homes delays this process. People need to accept the necessity of new waste treatment facilities, or face an environment tarnished by an abundance of untreated waste.

However, the role of the public should not stop there. In accepting waste disposal, people should encourage recycling as the dominant approach. Not only should they welcome recycling plants in their local area, they should also actively use such facilities and encourage local authorities to provide for their recycling needs.




Why Recycle?

When unwanted products such as glass bottles and jars are simply discarded, the natural resources, energy and time that went into making the product are simultaneously wasted. A large proportion of the resources that are used in manufacturing products and providing services cannot be replaced – these resources are non-renewable.

Increasingly, people are recognising that sustainable practices such as recycling make both economic and environmental sense. Recycling reduces the demand for raw materials that are used in the manufacturing process. For example, every tonne of recycled glass that is used preserves 1.2 tonnes of raw materials.

Glass recycling is a particular area with scope for improvement. The 20 per cent gap between the glass recycling proportions of the UK and the European average shows that improved standards are easily possible in the UK. New glass is made from a mixture of sand, soda ash, limestone and other fine-grained materials that are quarried; however, 80 per cent of the composition of glass bottles can be made from reclaimed scrap glass, known as ‘cullet’. Glass can be recycled indefinitely, since its structure does not deteriorate when reprocessed.

The ‘Waste Hierarchy’

The options for dealing with refuse material can be explored via the waste hierarchy, with the most sustainable heading the hierarchy:


Unfortunately, disposal dominates processing methods, with landfill comprising 75 per cent of the UK’s waste disposal. Recycling contributes 16 per cent and incineration with energy from waste 9 per cent.

Recycling recovers materials by preventing them from being discarded, and reconstitutes them into new goods. This may involve the recreation of the same product, or turning the old material into a new product. Recycled glass bottles can either be reconstituted into new bottles, or be used for other purposes such as road materials. In the UK, the average bottle contains over 25 per cent of recycled glass. Green bottles contain at least 60 per cent recycled glass, and sometimes as much as 90 per cent.

However, the economically and environmentally most efficient method of reducing waste is to avoid its generation in the first place. This requires producers to redesign products to increase their durability and, with regard to electrical and mechanical goods, to make them easier to dismantle so that the components can be re-used. For consumers, adopting more sustainable consumption patterns, such as not replacing items until necessary and purchasing second hand goods, can achieve waste reduction.

Green Glass Innovations

It is towards these goals that the Cornwall based company, Green Glass UK, has aspired. By converting empty, discarded bottles into elegant glassware, Green Glass UK is eliminating the need to manufacture glass from newly quarried materials.

The concept was pioneered by South African entrepreneurs Sean Penrith and Philip Tetley, who hold a worldwide patent on the unique conversion process. As casualties of a wave of unemployment in South Africa in the 1990s, Penrith and Tetley stumbled across the notion at a dinner party. It was at the dinner party that someone voiced dismay at the wasteful process of discarding used bottles. The idea then struck to separate the base of the bottle from its body, turn the main body upside down and reattach the neck to the base, thereby converting it into a drinking glass.

It then took Penrith and Tetley eight months of smashing bottles to create a prototype. It was the technique of joining the neck to the base that was problematic, and had large-scale glass production companies baffled. Just two years after developing the concept, Green Glass won the ‘Business of the Year’ award in 1994 and was voted among the four best new businesses in South Africa.

Having seen the concept in action in South Africa, environmental professionals Glenn Slade and Jo Traill Thomson established Green Glass in the UK. The company is rapidly expanding across the world, with new manufacturing facilities in the USA and Germany. Around 25,000 goblets, tumblers and drinking glasses are manufactured each month at the production facility near Johannesburg, South Africa.

The Manufacturing Process

The process of converting unwanted bottles into retail quality glasses has developed since its early days of collecting bottles from bins in Johannesburg and cutting them by hand. Today, bottles are received from recyclers all over the USA, the UK, South Africa and Germany and donated to the respective conversion plants.

The bottles are washed and sterilised in a bottle washer. They are then separated into two sections, the ‘head’ and ‘base’. The clean-cut separation is made by cutting a shallow line around the bottle, which is heated with a gas jet. When this is exposed to extremely low temperatures, a clean break is achieved. The head and the base are smoothed, paying special attention to what is to become the drinking edge, which is ground down and melted into a smooth edge.

For tumblers, the base (the lower portion of the bottle) is used. For goblets, the head (the upper section) is used. The neck is heated and flared, and then twisted and closed off from its new base. The newly formed drinking glasses are then passed through an annealing (tempering) oven to remove the residual stress in the glass. This makes them as durable as any glass on the market. The product is finally sandblasted for aesthetic effect.

Corporate Support

With environmental issues heavily on the global political agenda, many corporations are seeking association with environmentally friendly practices. The success of this recycling initiative has seen a number of leading beverage manufacturers turn to Green Glass to enhance their own ‘green’ image.

Beverage companies spend a great deal of time and money designing brand logos and trademark bottles. Green Glass has helped in extending such branding by fashioning the trademark bottles into unique styles of recycled drinking glasses. Each glass retains the unique contours of the original product, providing an image that consumers will immediately identify with the associated brand. Logos reinforce the image, meaning that non-beverage companies can also make use of the environmentally friendly status attached to the glasses. Customers for this service have included BMW, Beecham, Minolta, Valpre Spring Water and Seattle Coffee Co.

A Global Market

The success of Green Glass in penetrating the global market with a completely recycled product serves as a model of environmental good practice the world over. The expansion of Green Glass into the USA, the UK and Germany is helping to reduce the demand for traditionally made drinking glasses and therefore the demand for raw materials.

This global market for a product that is gentle on the Earth’s resources also demonstrates the economic benefits that can be derived from recycling initiatives. With innovative ideas in other areas of recycling, and help with finance, the world’s poor have a chance to lift themselves out of poverty.


The case study draws on articles published by Green Glass, the Institute of Civil Engineers and Wastewatch.

TVE/ITDG gratefully acknowledge support for Hands On programmes from the UK’s Department for International Development (DFID).

Further Information


Emel, J., Bridge, G. and Kruger, R. (2002) The earth as input: resources, in Johnston, R.J., Taylor, P.J. and Watts, M. [Eds.] Geographies of Global Change: Remapping the World. 2nd edn. London: Blackwell: 377-90.

Institute of Civil Engineers. (2004). State of the Nation Report: An Assessment of the UK’s Infrastructure. London: CIE.

Potter, R.B., Binns, T., Elliot, J.A. and Smith, D. (2004). Geographies of Development. 2nd edn. Harlow: Pearson.

Relevant Organisations

Green Glass UK

Institute of Civil Engineers (ICE)


Waste On-line


ITDG Technical Briefs

Other Relevant Hands On Case Studies

Green Endings
Waste to Wages