Wind power close to the city centre

When I first worked on this image of historic windmill sites around Brighton I was more interested in the terrain:.

Most mills are located on ridges or close to the coast to take advantage of the smooth air flow coming off the sea to the southwest.  Equally interesting is that they within the urban parts of Brighton and Hove whose population grew rapidly in the 19th century.  In paintings, wind and water mills are usually depicted in rural settings and most surviving structures are in rural areas where nobody wants a block of flats.  Yet in many big towns, flour milling was an urban industry.  The Moulin Rouge in Paris maybe better known for its performance of selections from the works of Offenbach, but the theatre was built on the site of one of the many windmills providing the Parisians with flour.  19th century milling techniques produced flour with a short shelf life, flour produced in modern plant will keep for several months, thus it made sense to have mills close to the bakeries.

Well into the 20th century, corn was cut in the fields during August and September and then gathered up into sheaves to dry and later stacked in such a way to protect it from the weather.  There it remained until labour was available for threshing to separate the grain from the stalks.  Originally, threshing was done manually and provided employment farm labourers when there was no other work available.  As with many other agricultural tasks, machines were invented to do the work.  During the Second World War, one of the tasks of women in the Land Army was to operate threshing machines which were moved and powered by tractors.

The peak of windmill building took place in the first half of the 19th Century, the graph below was estimated from an article in Wikipedia:

Most mills were built when demand for food in the expanding cities was growing and farming was a prosperous industry.  In the second half of the 19th Century, two trends emerged which were to bring about the demise of wind powered flower milling, both of which are related to the rise of steam power.  Steam ships enabled bulk cargoes to be moved across the oceans cheaply, this allowed the large wheat producing regions of North America to access the British market which in turn led to a fall in prices and a recession in British farming. The ports where the imported grain was landed also had access to coal from the mining areas of North East England and South Wales.  Thus flour milling became one of the industries based on sea ports alongside electricity generation and gas works.

This post is related to my interest in the economics of sustainable energy.  Whilst wind is the only thing that a modern electricity generating wind turbine has in common with a flour producing wind mill, I thought it would be interesting to attempt to understand the economics of windmills.  First, it seems that whilst milling might be seasonal, it was not directly related to agricultural production.   Flour could not be stored for long but grain could, so the mills needed to operate throughout the year.  Secondly, windmills declined because of the lower cost of alternatives, of which the availability of cheap transport was a significant element.  Also, as town expanded, the sites occupied by windmills had greater value as sites for housing.