The market
It is estimated that the world uses 3.2 trillion containers of all types each year to package food and beverages – and this number continues to grow. Almost all of it ends up as waste. Glass is a minor component. Each year, some 100 billion glass bottles and jars are produced in highly automated facilities that can crush up to a million bottles a day, each with an average value of less than half a dollar. Besides packaging glass, flat glass is used in homes and cars, accounting for 44 million tons. The flat glass market is valued at over $50 billion annually. Glass as a whole is a $100 billion market.
Glass has been produced for 9,000 years, and the first bottle appeared 3,500 years ago. Yet, recycling bins were only introduced in the 1970s. While countries like Sweden achieve a recycling rate of 90%, the US average is less than 40%, with California leading the way at nearly 80%. The UK has a strong preference for glass containers, with an estimated 8 billion units, or 3.6 million tons, of which less than one million tons are recycled. The rest ends up in landfills.
Glass is made from silica-rich sand and can be reused indefinitely. The glassmaking process is energy-intensive. One ton of virgin glass requires four gigajoules of energy. Transforming used bottles into new containers reduces carbon emissions by about 17%, while also avoiding mining. However, recycling is expensive. Members of the European Union and many US states have implemented deposit schemes that improve the economic situation. Charging as little as 5 cents per container in America and 25 cents for a one-liter bottle in Europe creates a secondary market. Unfortunately, the high cost of collection, transportation, and the requirement to separate by color has not been offset by taxes and fees. Even large-scale campaigns by consumers and governments do not seem to increase glass companies' appetite for more recycled glass. As a result, it is estimated that 65 billion bottles and jars are wasted every year.
Innovation
Recycling bottles into bottles might seem logical. However, asking trees to transform leaves back into leaves in the spring makes no sense from a physical, chemical, or biological perspective. Just as leaves are transformed into soil by microorganisms, fungi, and earthworms, the innovation conceived by Andrew Ungerleider and Gay Dillingham in the United States involves transforming non-recyclable mixtures of white, green, and brown glass into a glass foam with a wide range of potential applications, except for bottle manufacturing. It seems that the bottle itself is the bottleneck to reusing this natural resource.
Grinding used glass into powder, heated by injecting CO2, creates a lightweight yet abrasive, strong, and inexpensive foam. With landfills keen to reduce their load, on-site glass recovery and local processing into glass foam is giving rise to a new economic model: "entrepreneurs are paid to receive raw materials." The innovation isn't limited to a cascade of materials where one company's waste becomes another's input; it extends to the business model itself, where key ingredients come with money. Furthermore, if the plant is located near (or even on) a landfill, the production facility could benefit from the methane generated by the decomposition of organic waste, transforming this greenhouse gas into a cheap energy source, thus reducing costs while further mitigating its negative impact on climate change.
The first cash flow
Ungerleider and Dillingham then founded Earthstone in 1994. Driven by their desire to reduce open-pit mining, they transformed a known technique into a new business and quickly found an easy entry into the niche market of physical abrasives. Blocks of recycled glass, with air bubbles and tough diatomaceous earth-like frustules, can be used to clean a barbecue grill, remove paint, or smooth fiberboard. Since the handling is limited to cutting blocks of glass foam into easy-to-handle abrasives, and the competition is expensive and has a well-documented negative impact on the environment, supply stores like Home Depot began to carry the recycled glass-based product. Once initial sales were confirmed, production increased and improved as they progressed along the experience curve, moving from a batch to a continuous system, using more and more local, lower-cost materials, and thus becoming more competitive.
The opportunity
The range of applications is vast. While the American company Pittsburgh Corning, using a similar technique, decided to focus on the construction materials market, with its first glass recycling plant in Belgium and a second in the Czech Republic, Ungerleider and Dillingham discovered a wide range of applications. Today, Earthstone has eleven applications for recycled glass on the market. The latest involves providing hydroponic agriculture with a growing medium made of glass foam, which can be permanently recycled, thus eliminating a waste stream that was burdening this industry.
Swedish building contractor Åke Mård, based in Sundsvall, Sweden, took blocks of glass foam and transformed them into prefabricated foundations, walls, and even roofs for houses. He discovered that the glass—filled with tiny air bubbles—serves as a fire-resistant structural building material, not just insulation. This innovative construction technique has been approved by the European Union. No water penetrates these blocks, no vermin can find their way through the walls, no mold grows in the basement, and the insulation surpasses known alternatives in terms of both price and performance. Mård realized that recycled glass fulfills four functions while also serving as the physical structure.
The critical mass needed to operate a commercially viable furnace is estimated at 5 million bottles per year. In 2009, Earthstone processed 5.3 million bottles per year and was profitable. Considering a consumption of 200 glass bottles per family per year, approximately 25,000 families are needed for this business to be viable. The barrier to entry is relatively low. The main cost is energy, which could be supplied by a company with waste heat recovery capabilities, similar to natural systems, or derived from methane gas from the organic waste that typically accompanies glass production. The creation of these plants generates jobs, while improving the quality of building materials at competitive prices, fostering entrepreneurship, and reducing the need for transportation and extracted materials.
