By Gregory Brew
Far out to sea, amid the crashing waves of the North Atlantic, there’s a fortune to be made. According to new research, deep water wind farms could produce enough energy to meet all existing and future electricity demand, if properly harnessed.
In a study published on October 9 by researchers at the Carnegie Institution for Science and Stanford University, it’s estimated that deep water offshore turbines could produce three to five times as much energy as land-based turbines, due to the higher speeds and consistent force of the wind at sea.
One ‘small’ wind farm, covering 70 thousand square kilometers, could provide enough electricity to power the entire United States for ten years, according to the study.
A major factor in generating wind power is the movement of energy from higher in the atmosphere to the surface, where the turbines can transform it into electricity. The researchers found that land-based turbines are limited by the movement of atmosphere over land, which tends to be slowed down by the turbines and other impediments, such as buildings, trees or geographic features.
But this is less of a factor in deep water, where the ocean releases fantastic amounts of heat, particularly during the winter. With fewer impediments, atmospheric movement tends to be much more intense, allowing turbines to capture more energy with greater reliability
The researchers concluded that constructing deep water wind farms would not measurably slow the movement of this energy. While energy production in the winter months of the North Atlantic would be high, the researchers concluded that significantly less energy would be produced during the summer.
At the moment, these findings are necessarily speculative. Construction of deep water wind turbines, most notably floating turbines that don’t need to be fixed to the ocean floor, is in its early stages. Limitations to the technology remain considerable, as no one has yet determined how the energy produced from deep water turbines would be transmitted to shore, except via transmission lines.
One farm, the Hywind Scotland pilot project, consists of five turbines twenty-five kilometers off the coast of Scotland, capable of generating 30 MW of power. Hywind was partially funded by Norwegian oil company Statoil, which which hopes to use it to demonstrate the feasibility of deep water wind technology. Once complete in late 2017, Hywind will demonstrate the capabilities of deep water wind technology for the first time and produce enough power for around 20,000 homes.
Another deep water wind farm is planned at Dogger Bank by Statoil and British firm SSE. The project includes three separate facilities, and is capable of producing 1.2 GW of power. The farms will be located between 125 and 195 kilometers from the coast.
Offshore wind is a major factor in European energy, but has yet to make much of a splash in the United States. Compared to 3600 European turbines capable of producing 12.6 GW, the U.S. boasts only a handful of offshore projects, most of which are still being developed.
The global offshore industry was worth $20.3 billion in 2016 and is expected to grow to $57.2 billion by 2022, according to a report from Zion Market Research. Declining costs made the formerly prohibitively expensive offshore wind a much more affordable proposition—costs have fallen 32 percent over the past five years.
Most of the new growth in wind won’t come from Europe or the U.S., but from China, which is set to increase offshore wind capacity fourfold by 2020.
Yet there’s potential for the United States to harness offshore wind, and estimates indicate near-shore turbines could produce as much as 1600 GW if the full capacity was harnessed.
Substantial challenges remain for developing offshore or deep water wind energy. Expertise is in short supply, as few companies possess the means to manage such complex projects. Based on the success of projects on the U.S. East Coast and in Europe, however, it’s possible that offshore wind will be aggressively developed, particularly now that renewable energy continues to grow as a major source for global energy demand.