Carl von Linde
Carl von Linde was a multi-faceted engineer and scientist. After obtaining a patent in 1877 for the world's first modern refrigerator, he founded the company Gesellschaft fur Linde's Eismachinen, now Linde AG, in Wiesbaden in 1879. Based on his innovative work in the "process for liquification of atmospheric air or other gases" he was awarded another German patent in 1895. He was among the first in the world to produce large volumes of liquid air, and in 1902 began constructing his first Air Separation Unit. These plants liquify air to separate nitrogen, oxygen and argon, and today Linde has constructed over 2,700 worldwide.
The Linde Group has annual sales exceeding $8.5 billion with over 46,000 employees working in 53 countries in Europe, North America, South America, Asia and Australia. Linde has three main business segments - Industrial Gases and Engineering, Material Handling and Refrigeration.
AGA AB was started in 1904 near Stockholm, Sweden, by Gustaf Dalen, a 35-year-old engineer and ingenious inventor. The very next year AGA developed an automatic lighthouse mechanism that included the sun valve and the intermittent light regulator (the first innovations patented by AGA). Acetylene, with its bright light, was an excellent fuel for lighthouses, but it was too expensive when burned all day.
AGA's intermittent light regulator reduced fuel consumption by 90 percent, and the sun valve cut consumption by another 4 percent. This meant lighthouses could be operated at a low cost and left unattended for long periods of time. In 1912, AGA won a contract to build a lighthouse system for the Panama Canal and Dalen was awarded the Nobel Prize in Physics for his inventions in lighthouse technology.