Knot (unit) fluids (tidal streams, river currents and wind speeds) are also measured in knots. Thus, speed over the ground (SOG) (ground speed (GS) in aircraft) and rate of progress towards a distant point ("velocity made good", VMG) are also given in knots. Until the mid-19th century, vessel speed at sea was measured using a chip log. This consisted of a wooden panel, attached by line to a reel, and weighted on one edge to float perpendicularly to the water surface and thus present substantial resistance to the water moving around it. The chip log was cast over the stern of the
Wind power in Germany behind China and the USA. Since 1995, onshore wind energy has been an important and major industry in Germany. In 1995, the total onshore wind installed capacity was 1,530 MW. By 2018, onshore wind power installed capacity reached over 88 GW, which allows Germany to power about a fifth of the country from wind. Larger onshore installations are in the works, which could possibly see a larger percentage of wind energy powering Germany. Offshore wind energy also has great potential in Germany. Wind speed at sea is 70 to 100% higher than onshore and much more constant. A new generation