Tikalon Blog by Dev Gualtieri

Offshore Wind

March 4, 2024

The popular science and technology themed television sitcom, The Big Bang Theory, ran for twelve seasons and 279 episodes from 2007-2019. The peculiarities of scientists and engineers were exaggerated for comedic effect, especially in the case of physicist, Sheldon Cooper. Sheldon had many strange interests, such as creating an online video series called Fun with Flags.[1] The first episode of the video series, Bavaria, had Sheldon's girlfriend dressed as a pretzel. Several flags that missed Sheldon's attention were those associated with the Beaufort wind force scale, as shown in the figure.

Warning flags associated with the Beaufort wind force scale. One pennant signifies wind speeds of 22-33 knots (25-38 miles per hour), two pennants signify wind speeds of 34-47 knots (39-54 miles per hour), and a square flag signifies wind speeds of 48 and higher knots (55 and higher miles per hour).

My baby boomer generation is known to be strange for many traits, a precursor of which might be the fact that I learned these in elementary school. (Created using Inkscape.)

This wind force scale was devised in 1805 by Royal Navy officer, Francis Beaufort(1774-1857), as a means to quantify wind speed data in ships' logs. Its first use was during the 1831-1836 voyage of the HMS Beagle with Charles Darwin on board. Wind force was initially observed by its affect on a ship's sails; but, with the advent of steam power, the wind force was estimated by the height of sea waves. Presently, there are electronic instruments that give a more precise measure.

**Beaufort Wind Force Scale**
Scale	Winds	Knots	Miles/Hour	Kilometers/Hour
0	Calm	≤ 1	≤ 1	≤ 2
1	Light Air	1-3	1-3	2-5
2	Light Breeze	4-6	4-7	6-11
3	Gentle Breeze	7-10	8-12	12-19
4	Moderate Breeze	11-16	13-18	20-28
5	Fresh Breeze	17-21	19-24	29-38
6	Strong Breeze	22-27	25-31	39-49
7	High Wind	28-33	32-38	50-61
8	Gale	34-40	39-46	62-74
9	Strong Gale	41-47	47-54	75-88
10	Storm	48-55	55-63	89-102
11	Violent Storm	56-63	64-72	103-117
12	Hurricane	≥ 64	≥ 73	≥ 118

Wind was important to the ancient Greeks, who were a seafaring people. As I wrote in a previous article (Educated Guessing, December 7, 2020), Book II of Homer's Iliad lists 1186 Greek ships that transported troops to fight in the Trojan War. The Greeks personified the four winds, called the Anemoi, as gods, with Boreas as the north wind, Zephyrus as the west wind, Notus as the south wind, and Eurus as the east wind.

The winds were mysterious enough to the ancients that they were considered to be gods. Science has replaced this romantic notion by explaining wind as a consequence of a temperature gradient between regions heated by the Sun. Since air above land heats and cools faster than the air above water, warm air above land expands and rises by insolation during the day. This causes heavier, cooler air to rush in to take its place, thereby creating wind. At night, this process is reversed. Strong winds are the principal reason why siting wind turbines offshore is a sensible approach.

Wind speed map for the U.S. offshore wind energy technical resource area

Wind speed map for United States offshore wind energy. (Figure 17 of Ref. 3.[3] Click for larger image.)

One obstacle to offshore wind power has been community resistance to having wind turbines spoil the ocean view from their beachfront homes. However, people are now seeing that transitioning away from fossil fuel energy is essential to preventing their beachfront homes from being washed into the sea. There were also concerns that offshore wind turbine operations would adversely impact the marine ecosystem and fishing. As the following map shows, the United States has considerable wind energy throughout the contiguous 48 states, albeit less than the wind energy offshore. Siting wind turbines on land allowed an early access to wind energy, since erecting a wind turbine on land is easier than at sea, and there is an easy connection to the terrestrial power grid.

U.S. Average Annual Wind Speed at 80 Meters

United States average annual wind speed at 80 meters. An average wind speed greater than 6.5 meters per second is suitable for wind power development. Wind turbines higher than 80 meter have access to greater wind speeds. (United States Department of Energy map, also available as a PDF file here. Click for larger image.)

As I first read on Slashdot, one of my favorite computer technology websites, a portion of the first large scale United States offshore wind project, Vineyard Wind 1, achieved first power on January 2, 2024.[4] On that date, one turbine provided about five megawatts of electricity to the power grid. Vineyard Wind 1 was the first United States offshore wind project to get full federal approval.[5] Vineyard Wind 1 is placed in federal wind energy area OCS-A-0501, which is 15 miles south of Martha's Vineyard and Nantucket (see map).[6] When completed, Vineyard Wind 1 will have 62 turbines with 321-foot-long blades spaced about a mile apart providing up to 800 megawatts of power through subsea electrical cables to mainland Massachusetts, 35 miles distant.[5] That's enough power for 400,000 homes.[5]

South Fork Wind, a much smaller offshore wind project off Long Island, New York, began producing electricity in early December, 2023.[5,7] When completed, this 132 megawatt wind farm will supply electricity to 70,000 homes in East Hampton, New York, the easternmost town in the state of New York. Its twelve turbines will not be visible at the East Hampton beaches.[7]

Location of Vineyard Wind 1.

(Created using Inkscape from this base map, and data from Vineyard Website.[6] Click for larger image.)

Offshore Wind

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