BASF provides salt for the world's biggest solar project in Dubai
May 16, 2019
Dubai was long one of the cities with the highest water and power consumption per capita in the world; in fact, consumption was significantly higher than in the United States or Germany, for example. However, for the past few years, the city on the Persian Gulf has expanded considerable effort to reduce its power consumption, while simultaneously drawing energy from renewable sources. The goal is to secure 75 percent of Dubai’s power needs from renewable energies by 2050.
The Noor Energy 1 project marks a major step towards achieving this goal. Noor Energy 1 is currently the world’s largest solar project: a total of 950 megawatts is to be generated as of the end of 2020. To achieve this goal, the project operator is relying on state-of-the-art concentrated solar power plants: a solar tower power plant, three parabolic reflector power plants and a solar power system.
BASF is the sole supplier of high-quality sodium nitrate for the solar tower power plant – a total of roughly 100,000 tons of the inorganic salt produced in Ludwigshafen will be shipped to the Gulf over the coming three years. The necessary contracts with the project’s engineering partner, Shanghai Electric Group Co. Ltd (Shanghai Electric), were signed in January.
The salt’s purity plays a crucial role
BASF is one of the few companies that produces sodium nitrate chemically, with mining providing an alternative extraction method. But the greatest benefit of the chemically produced salt is its purity: the fewer magnesium or chlorine remnants in the salt, the better it is suited for use in a concentrated solar power plant.
These power plants work on the principle that the sunlight is concentrated in order to heat the sodium nitrate until it melts. When the sun is shining, hundreds or thousands of mirrors automatically align themselves to reflect the sunlight to a central absorber. In the case of the Noor Energy 1 project, this is handled by a 260-meter-high tower – in itself a superlative. The extreme concentration of sunlight at the tip of the tower produces temperatures of up to one thousand degrees Celsius. The liquefied nitrate salt is pumped in a circuit and used to transfer the thermal energy of the sunlight to a water circuit via a heat exchanger, the steam from which drives a turbine, thereby producing electric power.
“This makes it clear why the purity of the salt is so vital: the inorganic heat-conducting liquid heats up to 500 degrees Celsius. Impurities in the liquefied sodium nitrate can promote the partial decomposition to sodium nitrite and, for example, magnesium or chloride. The decomposition products can in turn damage the plants through corrosion and formation of deposits. The more impurities in the salt, the greater the impact of resulting damage,” explained Manuel Altarriba, Sales Manager at BASF Inorganics, E-CMI/B. “We have stringent quality control procedures in place and we conducted close-meshed sampling in our labs to ensure complete quality assurance for the entire delivery quantity.”
Reliability is particularly important in this complex project
Alongside the product quality, delivery reliability was also an important factor for Shanghai Electric when it came to selecting BASF as a contracting partner. “The project in Dubai is a global project – starting with the project owner, to a Chinese Bank, to a Shanghai Electric joint venture BrightSource and many other component suppliers from around the world. We must be able to rely on our business partners to ensure that the project is successful. We are convinced that BASF will fulfill all the agreements,” emphasized Yin Haisheng, Vice Project Director at Shanghai Electric.
“We are very pleased that we could convince Shanghai Electric that BASF is the right partner for the project,” added Michael Wind, Vice President Inorganics, E-CMI/B, in Ludwigshafen. “This shows that there are always new and innovative applications, also for products that have a long tradition at BASF,” Wind added.
BASF has been producing sodium nitrate in Ludwigshafen for over 90 years. Along with its use in the solar industry, it is primarily used in the processing of glass and foods. BASF supplies its salt to all solar tower power plants around the world: clear proof of BASF’s outstanding product quality.