Scheuten/Interpane Joint Venture

• New highly transparent low-iron float glass for photovoltaic and solar thermal applications
• Special production for the solar industry
• Flash test confirms unsurpassed values for energy transmission

f | glass GmbH, in Saxony-Anhalt’s “Glass Valley”, Osterweddingen, has had a successful start and is producing up to 700 tonnes of float glass a day. The company is focussing on the production of a new high end solar glass and its subsequent processing into the finished product: “f | solarfloat” achieves unsurpassed values for energy input into the solar module and thereby increases the “solar yield”.

This has been confirmed by first flash tests under standardised test conditions (STC). The float glass plant of the joint venture between the Dutch Scheuten Group and Interpane Glas Industrie AG is currently the only one of its kind worldwide: The special design of the melting tank and the materials used enable the fully continuous production of extremely low-iron solar float glass.

The plant has been tailored to the requirements of the solar industry: Cutting into any format, edge treatment, glass coating by means of magnetron sputtering, tempering as well as customized logistics – everything is carried out here.

About 6,000 people applied for the approx. 250 new jobs at f | glass – in one of the most modern industrial glass productions worldwide. In the meantime, production is in full swing at a melting capacity of 700 tonnes of float glass per day. In order to meet all the special requirements of the growing market of the solar industry, the company features glass coating, cutting, glass processing, and a tempering furnace.

European sales for f | solar GmbH benefit from its location, which meets all the important requirements, from the supply of the purest raw materials for the glass production to the excellent logistical conditions.

Sustainable production

f | glass also sets new standards in terms of energy efficiency:  Osterweddingen provides short transportation routes for raw materials and glass products – this minimises the CO2 emissions.

The innovative design of the furnace reduces the energy input per tonne of glass: Through a combined heat and power cycle, the plant generates energy from the hot emissions of the furnace and extracts steam for heating buildings and plants. In addition, the flue gas purification plant drastically minimises particle emission: 100 per cent of the dust from the flue gas purification is recycled and reintroduced into the glass melt as a raw material.

In the end, the exhaust air from the production process is verifiably cleaner than the ambient air. The enormous roof area of the production hall is also being used: A 3 megawatt photovoltaics plant feeds considerable amounts of power into the grid, which is achieved by using particularly highly transparent low-iron glass.

A comprehensive energy management system (EMS) coordinates all the energy “consuming” components during production – power, gas, compressed air, and water. A closed cooling water supply system cools the units and also reduces the use of fresh water.

Fully continuous production

At the beginning of the production process is the mixture: The receiving and storage of raw materials as well as the weighing and mixing of sand (60%), soda (19%), dolomite (15%), and other materials at approx. 25 degrees Celsius. Then, the route through the heat starts at a draw rate of 2 to 22 metres per minute: Inside the melting furnace, the mixture is heated to 1,580 degrees Celsius.

In the tin bath with flame polishing, which is protected by roof heating and inert gas, the shaping takes place at approx. 1,100 degrees Celsius. Subsequently, the glass panes are slowly cooled and released of stress in a lehr at 600 degrees Celsius. The final quality assurance, cutting, handling, and storage then follow in the cutting line.

In one of the largest high-capacity production glass coater worldwide, high-quality coatings are applied to the float glass under vacuum. The product range focuses on robust antireflective coatings and so-called “low emissivity” (low e) coatings for low-energy glazing.

The glass processing line constitutes the end of the process: Glass cutting, edge cutting, automatic dust-reduced scrap removal, drilling, “on-line” quality inspection, high-capacity production tempering, as well as customised packaging. All of this happens in the form of a fully continuous production process and in turn guarantees consistently high quality all from a single source.

f | solar GmbH customers can choose from a complete series of solar products:

• f | ecofloat
  back glasses for thin-film photovoltaics
• f | ecofloat T
  as the tempered safety glass version
• f | solarfloat
  a particularly low-iron solar float glass for the front glazing of photovoltaics modules or cover glazing for solar thermal collectors
• f | solarfloat  T
  as the tempered safety glass version
• f | solarfloat HT
  the top product of the highly transparent low-iron solar float glass series, tempered and coated with up to two additional antireflective layers, which considerably increase energy transmission even more