A random history of energy economics (3) - The life cycle of fuels

Fuels like any other product have life cycles.  The stages of the classic life cycle are growth, maturity and decline.  For some fuels like wood, the length of the cycle is measured in millennia, that of coal looks like it might be centuries and carbide probably decades.

My understanding of acetylene lamps is that they were developed for cars and motorbikes at the very end of the 19th century.  Whilst electric incandescent lamps could be powered by a lead-acid accumulator, they were not bright enough to allow safe driving at speed.  The attraction of acetylene is that it burns at a high temperature and produces a bright light.  The gas was generated by the action of water on calcium carbide, the lamps were so constructed that a reservoir of water dripped on calcium carbide which was then burnt in a lamp with a reflector.  The brightness of the lamp was controlled by adjusting the water flow, as the gas was generated, the carbide turned to slaked lime.  "Carbide" was sold in garages along with petrol and oil during the 1920's, but as automotive electrics improved and effective headlamps which could be controlled by a switch became a standard fitting, carbide lamps were largely displaced by the 1930s.

Kerosene (a.k.a. paraffin) as a domestic fuel had a somewhat longer life cycle, it was used for lighting and cooking in late 19th century.  In the era of solid fuel ranges. it facilitated cooking without first having to light a coal fire, although many found the smell unattractive.  Paraffin heaters were widely used well into 1970s and may people remember the Esso's adaption of "the smoke gets in your eyes" for their TV adverts.  Paraffin heaters were generally displaced by low cost gas central heating in the 1970s.

The same pattern of growth, maturity and decline is apparent in the UK coal consumption.  A spokesman for OPEC once commented that the UK did not run out of coal, they just stopped using it.  In the latter part of the 19th century consumption grew as industry, the railways, gas production and other applications expanded.  It remained constant for approximately half a century until the 1970's.  During this time the economy was growing, but technology was evolving which allowed coal to be used more efficiently.  In 1890, electrical power generation had a thermal efficiency well below 5%, by 1970, this was approaching 40%.  The boilers used in the early power stations operated around 150 psi, by 1945 some were operating at 675 psi, the rising temperatures and pressures resultined in higher operating efficiencies.

In the 1960, natural gas (mostly methane) from the North Started to displace coal as a domestic and industrial fuel.

The displacement of coal by natural gas is apparent in the graph below.  Starting around 1830, many towns acquired as gas works either privately or municipally owned, in the early years the principal use was for lighting, but cooking, heating and industrial use increased.  Between 1900 and 1930, electricity, also generated from coal, displaced gas for lighting.    The availability of North Sea gas bought about the extinction of the coal gas works in less than a decade.

Gas turbine power stations, steadily displace coal fired steam technology, a process which accelerated in the 21st century as concerns over the environmental effects of coal grew.

Relevance for Today

The energy mix is constantly changing, the driving force is technology, over two centuries it has included coal, wind, nuclear (after 50 years is this an old technology) and many evolutions within each one.  There is a lot of evolving technology, offshore wind and electrical storage maybe the key elements.  Several cities are talking about petrol or diesel vehicles and only allowing electrical ones, so more change can be expected.

A Random history of energy economics (2) - The Horse and the Lorry

By 1900 railways were the most important element in Britain's transport infrastructure, but they only provided town-to-town communication.  The distribution of goods within a town was done with men with barrows and horses with carts.  In the rural areas "carriers" moved goods and people around with horse drawn wagons.  Horses were widely used well into the 1930s by which time motor transport was firmly established.

I came across some figures comparing the cost of coal distribution from depot to customer by 30 cwt truck and a horse and cart in 1931.  The figures seem to relate to an adequately funded and well run coal business.  Two points about the graphs, first they are for 1931 and are not comparable to costs in 2017 and that the original data is in pounds, shillings and pence which was converted decimal pounds for the benefit of Excel.  I have doctored the data a little for the sake of comparability.  In 1931, the price of domestic coal was between £1.50 and £4.50 per ton depending on the grade, local terrain and market conditions.  Anthracite was the premium product whist Bituminous coal was cheaper, also coke from gas works was widely used.

Both the horse and truck were depreciated over four years and  funded by money at 5%, the horse cost £90 and the truck £250.  The cost structures for both modes of transport is broadly similar, the exceptions are higher capital related costs of the truck, the legal requirements for a license and insurance and maintenance.  Food for the horse and fuel for the truck are similar as are the wages of the driver.

The big difference is the level of productivity, the horse shifts 38.5 tons/week, whilst the truck can do 49.5, but the unit costs are similar at around £0.20/ton.  I suspect that there was a lot of variation within the industry.  If only one man was employed to work with the truck, he would have to work harder than the bloke with the horse and cart, the references I have seen to coal sacks at this time suggest there were 1.25 cwt ( very roughly 62kg or very heavy, I struggle with 25kg bags of sand).  This might have been OK for a youngish man shooting coal into a cellar with street access, much less for an older one shifting the bag from the street to coal store in the scullery at the back of the house.


Some random reading suggests that the domestic coal market was split into three sectors.  At the top end would be customers that bought coal in large quantities, say greater than half a ton, possibly belonging to a "coal club"  which spread the cost more or less evenly over the year, trucks would give an advantage to merchants serving this group.  Those serving customers purchasing less than half a ton and paying the current market price might have a cost advantage from the potentially lower costs of the horse and cart.  At the bottom end of the market would be those purchasing small quantities of coal, possibly as little as 7 pounds would pay high prices to men with barrows.

A Random History of Energy Economics (1) - Gas Engines in the Home

Over the past year I've been acquiring a few copies of the "The Model Engineer and Amateur Electrician" at car boot sales.  I now have about 15 examples dating from 1899 to 1919.  Models make up a large part of the content, but there is also an informed debate on technology as it was evolving.  At the bottom of one page is a note that a Frenchman has observed that a platinum wire is heated with an electric current and then placed in a jar of methane continued glow.  I'm guessing that this curiosity was an early version of the catalytic converter found on most modern cars.  There are notes on telephones and wireless telegraphy and a discussion of the ideal way of storing energy to power motor vehicles, electricity is was thought to have potential and compressed air to be a bad idea.  Electric shock treatment must have been fashionable as some advertisers claimed it was better to be shocked by their apparatus than that of a rival company.  With hindsight X-Rays were not something the citizen scientist should be encouraged to mess with.  The classified ads can be intriguing, there is a suggestion that a vicar had a model gunboat to sell and why would someone expect to exchange an accordion for a lathe?

In the diversity of items advertised, three occur frequently, these are gas engines, dynamos and accumulators.

In 1905, electricity was still a luxury product costing may be 4d - 6d per kwh (roughly 50p in today's money) and many urban areas did not have a supplier and remote households had to generate their own electricity if they wanted it.  Gas, however was a mature technology, many gas companies had been established between 1820 and 1850 and most urban areas had a gas works.   In some coastal towns, the coal was supplied by brigs from Newcastle running themselves aground on the beach  and being re-floated after their cargo had been hauled away by horse and cart. The cost of gas might be something like 2s 6d and 3s per 1,000 cubic feet, depending on the nature of the gas this would be roughly 10p/kwh today.

At the turn of the century gas was increasingly being used for heating and cooking, but the principal application was lighting. Whilst gas lighting was better than candles, it could make the air in a room foul, the products of combustion being carbon dioxide, carbon monoxide and water vaoiur plus anything else the gas company could not get rid of.  Gas mantles required cleaning  and lighting, whilst electric lamps were clean and available at the flick of a switch.  Doctors wrote letters extolling the benefit to health of electric lighting.  It's not easy to make a like for like comparison with the cost of gas and electric lighting but it seems that electricity was perceived as being 5 - 10 times more expensive.

Fractional horsepower gas engine/dynamo sets provided a source of electricity where a public supply was not available and possibly a means of getting a supply at a lower cost.  At the time of writing, I'm still attempting to identify a property which had such an installation.  At a guess, a common configuration would be to have the machinery in a shed where it was used to charge accumulators which were in turn connected to the lighting circuits in the main house.  Voltages seem to have been in the range 4 - 12 volts and accumulators could be relative large, say more than 50 AH.

After 1900, the public electricity supply expanded rapidly, but in most places this was AC, whilst the use of DC in the home decreased, cars and motorbikes created a new demand and low voltage dynamos were used to charge automotive batteries.  Early radio sets also needed a DC supply.

The magazine has several references to water engines, for owners of landscapes which were suitable for the construction of small dams and there a few mentions of "hot air" engines, I take this to mean "Stirling" engines, but so far no description of the workings of these devices.

Art and Energy

The Brighton Museum is staging an exhibition of the work of John Constable which he produced whilst living in the town from 1824 to 1828.  I went because it's a form and period of painting I'm attracted to.  The space is quite low key and does not shout "great art" making it possible to appreciate the pictures for what they are, sensitive and imaginative depictions of Brighton and the surrounding countryside at the start of it's period of expansion.

What I did not expect was an insight into the energy economy of the town before the arrival of the railways.  There are several pictures of beached collier brigs.  After 1840 most Brighton and Hove's coal supply was came from the harbour at Shoreham by rail, but before that a lot of it was landed on the beach and taken to buyers in the town by horse and cart.

The collier brigs were two masted vessels of 100 - 300 tons with a length of between 70 and 90 feet and a small crew, maybe 6 - 10 men.  They mostly worked out of the Tyne taking a cargo of coal outward and returning home in ballast.  Some vessels also carried passengers between the North and London, before the railways this might have been preferable to several days in a coach travelling along rutted roads, at least in fine weather.  Navigational equipment was probably the master's experience and a compass.

At coastal towns like Brighton and Hove which did not have port facilities, the brig was run on to the beach and the cargo unloaded into horse drawn carts using local labour.  When the vessel was empty she was re-floated on the rising tide.  The price realised for the cargo would have depended on the season, the weather and before 1815 the trade could be disrupted by French privateers, this threat may have been used to hike the price.

Coal landed on the beach within the parish boundaries was subject to coal tax.  This explains the location of the Brighton Gas works (1819) just beyond the eastern parish boundary at Black Rock and the Hove Gas works (1825) which is at the extreme west of the town.  These works were located to avoid the coal tax.  Coal tax was abolished around 1870 and was not a factor in the location of electricity generating plant.  From 1820 to 1880 gas was used for street lighting and in  the posher town houses.  After the establishment of electric light companies in Brighton and Hove, gas lighting was displaced, initially by arc lamps, then by incandescent bulbs.

At the turn of the century the demand for coal in Brighton and Hove had greatly expanded.  In 1928 there were four railway goods yards, each of which acted as a base for coal merchants, some of these operated nationally, others were local family businesses.  Going west to east, the goods yards were located at Sackville/New Town Road (Hove), Holland Road (Hove), Cheapside (Brighton) and Kemp Town (Brighton).  With the exception of Cheapside which is close to the main Brighton station, these yards are now industrial estates doing amongst other things, serving the local building trade.

By the 1880s, the railway's coal distribution network was evolving at the same time as the market for coal for electricity generation emerging.  Brighton's first power stations were close to North Road and supplied from the Cheapside yard.  Hove's was at Holland road where it may have had it's own siding for coal deliveries.  At the end of the 19th century, the demand for electricity was growing and city centre locations for industrial plant was neither desirable or practical.    Brighton built a new power station at Shoreham harbour, close to the gas works which had already located, both the gas and electricity works were now supplied directly from the sea by steam engined colliers.

Industry attracts fewer artists and poets than traditional landscapes, seascapes and portraits, but there is one reference in John Masefield's "Cargoes" which is relevant.  I suspect generations of English teachers have hoped to inspire a love of words and rhythm with this, the last verse is:

    Dirty British coaster with a salt-caked smoke stack,
    Butting through the Channel in the mad March days,
    With a cargo of Tyne coal,
    Road-rails, pig-lead,
    Firewood, iron-ware, and cheap tin trays.

I've always been troubled by the "salt caked smoke stack", maybe I'm too literal, but the verse does invoke the rhythm of a reciprocating steam engine.

Footnote

I wrote this quickly from memory without checking the facts, please feel free to offer corrections.

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.