United Silicon uses a traditional manufacturing method and melts quarts (Silicon dioxide), blended with coal and woodchips, in an electric arc furnace, where the chemical reaction takes place at 1900 decrees Celsius:
The process is simple theoretically, but needs to be controlled precisely in the furnace, to achieve the right quality of silicon, energy efficiency and the right quality of microsilica (dust collected in the air filter), which is a by-product used in the cement and refractories industry.
The process can be illustrated in the following simple diagram:
United Silicon is a company in the silicon manufacturing industry, which is produced in the company´s Production Plant in Helguvik, where the first 32 MW electric arc furnace is located and produces silicon by melting quarts at 1900 degrees Celsius. The company supplies silicon to costumers mainly in the solar industry, the aluminum industry and the silicones industry, which ends up on more than 12.000 different end products sold all over the world.
Most people use silicon at least 3 times a day, when they brush their teeth in the morning (in toothpaste), when they wash their hair (in shampoo & balsam), use lotions (in most creams) and drive to work since there are silicones in all tires. Moreover we surround ourselves with silicones in our houses (in bathrooms and around all windows), our cars and the airplanes we fly in, since most finished aluminum materials are made as an alloy containing 2-10% silicon.
United Silicon´s production plant is designed and manufactured according to the highest environmental standards, and has a modern air cleaning filter installed which cleans all the exhaust air from the furnace, and removes all dust down to a size of 5 micro meters in size, thereby ensuring a maximum concentration in the surrounding air of the plant of 5 micrograms pr. m3, which is 4 times lower than the Icelandic air quality criteria set by law, of 20 micrograms pr. m3. Furthermore it is worth noticing that United Silicon´s Production Plant is designed without any “emergency stacks” which older (and some newer) plant s are equipped with, and enables the plant to emit unfiltered air directly from the furnace into the air. This is not made possible at United Silicon’s plant, where all the exhaust air is continuously emitted only through the air filter, and thereby always cleaned.
United Silicon´s air filter is a state of the art filter, using the newest Gore-Tex filter bags which removes 99,5% of the dust. The air filter alone costed 15.5 mio. EUR to construct and is a result of the founders of the company to have the best possible air filter available for this industry today.
Furthermore United Silicon has set up 3 air-quality measurement stations at key locations around the plant, which locations was strategically placed in cooperation with the Icelandic Environmental Agency (UST). United Silicon has arranged for the measurements to be broadcasted in real-time on the internet at andvari.is and thereby United Silicon is setting a new standard in continuous measurements and broadcasting of air-quality data, so the people of Reykjanesbæ, can follow this on a daily basis. This is more than any other industrial plant in Iceland is doing, and in fact the company is only obligated by law to submit a report on these measurements once a year, but the management has decided to use this open approach, to reflect the company´s policy to make people aware that the environment around the plant is in good condition, despite the unavoidable emissions from the production process, even after the air has been cleaned.
Emissions of greenhouse gasses
The production process in the plant results in unavoidable emission of carbon dioxide, which scientific consensus tells contributes to global warming. United Silicon has however significantly lower emissions of carbon dioxide than 90% of other silicon manufacturers in the world (whereof 60% are located in China), where the energy source for the smelting process is made in coal fired power plants which emit carbon dioxide in large scale. In Iceland all the power is produced with renewable energy, and therefore United Silicon’s emissions of carbon dioxide is 9 times less than the average silicon producer in the rest of the world. Since the world needs silicon it makes good environmental sense to produce it in Iceland, and United Silicon is proud to be able to “export” the renewable energy of Iceland as silicon, whereof about half of our production is used in manufacturing of solar cell which produce more renewable energy around the sunny parts of the world.
Furthermore United Silicon uses wood based charcoal produced in Poland and wood chips from Canada, both harvested from renewable forests, which are carbon neutral and therefore does not contribute to global warming, since the carbon dioxide is captured again by the growing trees.
Needless to say; the solar cells which are manufactured using the silicon produced by United Silicon in Iceland, are rapidly replacing coal- and gas fired energy production around the world, and we are proud to participate in this new growing industry. It is worth noticing as BBC announced this summer that 2016 was a new record for renewable energy in the world, where half a million solar panels where erected every day of the first half of 2016.