1929: The Ardnacrusha hydroelectric plant on the Shannon
As the 1920s dawned, few cities in Ireland had electricity. The total capacity of all public power plants came to only about 27,000 kilowatts. The Irish Free State, founded in 1922, had little in the way of coal deposits, so efforts went into using abundant local water power to connect the country to electricity and encourage its economic development. The territory to be supplied had a population of around three million at the time, and covered about 70,000 square kilometers (about 27,000 square miles).
In 1925, the government engaged Siemens to install electricity for the entire country. The heart of the power supply was the Ardnacrusha hydroelectric plant on the River Shannon, with three generators with a capacity of 30 megavolt-amperes (MVA) each. It was commissioned in 1929; the second phase, with another 25 MVA, was completed in 1933.
At the time, the contract to build this run-of-the-river, three-phase power plant was the biggest international contract to be landed by a German company since the Baghdad Railway, which began construction back in 1903. This large project gave impressive proof of Siemens' abilities as an international competitor.
1978: Work starts on Itaipú, the world's largest hydroelectric plant
In 1978, work started on the world's largest hydroelectric plant, on the border between Paraguay and Brazil. At its completion in 1991 the plant was generating 75 billion kilowatt hours a year, making it the leader not just in capacity, but in electric production.
Up to the 1991 completion of the plant in Itaipú on the Rio Paraná, Siemens supplied not only vast amounts of other components, but five of the world's largest hydroelectric power generators, each with a capacity of 823.6 megavolt-amperes (MVA). The generators were built at the plant in Lapa, Brazil.
The transformers as well were of an unheard-of size – each of the 275-MVA units was as tall as three men when ready to run, and weighed 215 metric tons. Just transporting these enormous components was a masterwork of logistics.
1994: World record fuel cell
Fuel cells can generate electric power directly from oxygen and hydrogen, in a process sometimes known as "cold combustion." Here efficiency is substantially greater and the emitted pollutants considerably less than with conventional power sources.
In 1994, a ceramic high-temperature SOFC (Solid Oxide Fuel Cell) at Siemens, running with hydrogen and oxygen, achieved an output of 1.8 kilowatts (kW) for the first time in the world. The previous maximum had been 1.3 kW. The power density of 0.6 watts per square centimeter was also an international record.
Critical power-up and power-down processes were also simulated during the battery's more than 300 hours of operation. As it turned out, the electrical performance figures were still unchanged even after a new power-up.
2012: The world's longest rotor blade
In 2012, the trial run of the world's largest rotor began at the six-megawatt offshore wind farm off Østerild, Denmark. It was equipped with the world's longest rotor blades to date – 75 meters long.
The new type of rotor blade stood out for its high stability combined with low weight. It was the world's largest single-cast fiberglass component, free from both seams and glued joints. A special blade profile ensured optimum performance at a wide range of wind speeds. A blade made by conventional methods would have weighed 25 to 50 percent more. Heavy rotor blades are exposed to heavier loads, and need stronger machine housings, towers and foundations. So the combination of smart design and low weight helped bring down the cost of generating wind power.
The turbine could produce 25 million kilowatt hours (kWh) of clean electricity in offshore locations – enough to power 6,000 homes.
2017: OWL technology
Wind farms do produce "green" electricity, but they also make noise. The faster a turbine runs, the louder it is. That is not a problem on the open sea, but on land there are a lot of requirements to protect neighbors from too much noise. Setback rules aren't enough by themselves. So wind turbines with conventional rotor blades often can't run at full power. Yet the slower they run, the less electricity they produce.
The innovative design of OWL rotor blades imitated an owl's feathers, with their fringed edges. It cut noise emissions from onshore wind turbines as much as 10 percent, thus reducing the need to turn down turbine output to comply with noise regulations, and increasing annual energy output 1.5 percent.
This "DinoTail Next Generation" technology combined the toothed structure of previous "DinoTails" with the new feather-like fringed edge – a major technological advance and an important competitive advantage in the onshore market.