Pages

Friday, 29 July 2016

Energy Alternatives

The electricity industry took shape in the 1880s.  Initially, it was a "luxury" product consumed by high income households.  Large establishments might have had their own generating plant, but rapid growth in the demand for electricity started when companies were formed to supply consumers from a local power station.  Either by choice or circumstance, many of these companies became owned by local councils, with a little stretch of the imagination, they could be described as being owned and controlled by the community they served.  By the start of the 20th century demand for electricity had grown and the original small power stations with reciprocating steam engines located in residential areas were too small and inefficient to meet the demand, these were displaced by large steam turbine plants located close to a coal supply such as a port, railway depot or even the mine itself.  This became the model used by the industry for a century and it worked well, energy will never be cheap, but its rare to flick a light switch and have nothing happen.  Big nuclear power stations fit into this model.


There are big differences between the late 19th and early 21 centuries, for political and environmental reasons it is desirable to reduce dependency on fossil fuels and many people are uncomfortable with nuclear power.  However, the technologies available make it possible to consider alternatives to the big generator model, for the foreseeable future big power stations will have a role, but it may be possible to stem their growth and possibly even displace some of them.

These comments are based on personal observations, but they may have some wider relevance:
  • Energy consumption can be reduced without a drop in living standards.  In our case, we have steadily migrating to LED lighting, 20 watt compact fluorescent lights have are being replaced by 10 watt or smaller LEDs.  As appliances have died of old age, energy consumption has a factor in deciding on the replacement.  The old washing machine consumed 1.5 to 2.0 kwh/wash, the new one typically uses 0.25 to 0.70 kwh.  There maybe environmental benefits, but our electricity bill is £23/month and falling.
  • Storage is a potential game changer in the way the industry works.  Demand for electricity peaks in the early evening when families are home cooking, staring at a screen or doing homework, at present supply and distribution is set up to meet the peaks and troughs of daily life, if every house had even a small amount of storage, maybe as little as 2kwh, it could be possible to run the generators under constant load with each household having a time slot for charging its batteries.  Grocery deliveries have made us familiar with delivery time slots, doing the same thing for electricity is not such a big step.  Back to economics, there is the potential for buying electricity at off-peak rates (7p instead of 15p/kwh), so there is some potential upside for the consumer.  Storage also helps integrate energy from wind farms in to the energy economy.
  • Back in 1900, if you wanted to generate your own electricity the main options were steam or gas engines, water wheels were an option for those living near a river and wind generation was still being explored.  Even under an cloudy English sky, solar panels can make a contribution.  At present, the economics of home generation are geared towards getting a return-on-investment, however, in conjunction with storage, there is the potential to displace some gas fuelled generating capacity.  Peak demand is in the evening when the sun does not shine bright, if energy generated during the day can be stored for use in the evening, then the load on the grid can be smoothed.  This requires some creative economics.  Some rough calculations suggest that our house's grid dependency would be decreased by two solar panel mounted somewhere other than on the roof.
  • Cars and vans contain reliable combined heat and power systems, a 2kw alternator provides electricity some of which is stored in the battery and waste heat from the cooling system is used to keep the cabin warm.  Extracting the appropriate components and packaging them as a consumer product might produce something costing less than £1,000, such an installation could produce heat and power during the winter months. These could be gas fuelled.  In the context of a car, this is established technology.  One of the incentives for the development of petrol and diesel engines was the limitation on consumption of town gas.  Any loss in efficiency in electrical generation could be compensated for by the use of waste heat.
Some of this stuff is fanciful and no doubt others could expand the list but the point is there are alternatives to big power station model.


Sunday, 24 July 2016

Energy and Adverts

I would like to say that I have a research plan for theses posts on the history of domestic energy, but it is just random reading and looking for holes in the pavement.  One source material is advertising.  Until the end of the 1960s, domestic energy was about shovelling, either you did it yourself or you paid someone else to do it.  For some, the 1960's might have been the Stones, the Beatles and the summer of love but for my mother it was gas central heating and the removal of the coal bunker.  As a family, we did our own shovelling but for some this was a problem to which this advert from the May 1931 edition of "The Sussex County Magazine" attempted to address.


The reference to "boilers" rather than "boiler" suggests that it was aimed at larger properties which probably included up-market blocks of flats with communal heating systems.  Often, these were not a source of happiness either being too cold or too hot or broken down and always too expensive.  Even in the depression, looking after one of these would not have been an attractive job.

The serious heavy lifting was done by the coal men, coal was delivered in bags weighing one and quarter hundredweight or 10 stones (roughly 60kg) which is the weight of a small adult.

Despite appliances being graded according to there energy efficiency, energy consumption in the kitchen is rarely the subject of today's polite conversation around the marble worktops. However, some old "domestic science" textbooks take it seriously  and pre-war housekeepers were expected to be aware of the amount fuel they were using.  This is reflected in this advert from the June 1936 edition of "The Sussex Country Magazine":


I'm guessing, but at the time this advert was published, coal fired stoves were competing with gas and electric cookers in the suburbs where a supply was available and coal/coke was cheaper per kwh than gas or electricity.  The claim that the fuel cost was £1.00/quarter suggests that consumption was around one and half tons per year (assuming coke to cost £2.50/ton at the time).  A ton of coal and it's residual ash requires a lot of shovelling.  The advert also features deferred payments, the gas and electricity companies also offered appliance hire and credit facilities.

The theme of shovelling is continued in the small ads.  You imagine the look of surprise and delight on the face of someone receiving one of these:

However, a modest sized house with coal fires could get through several tons of coal in a year, if the task of shifting the stuff from the coal store to the kitchen, living room and  bedrooms was eased, the bearer of the gift might be rewarded with a smile, unless the recipient had hoped for silk lingerie.

In the 1930s the use of mains electricity in the home was expanding with the acquisition of irons and vacuum cleaners, but there were a lot of battery powered radios in use.  Typically these used lead acid accumulators to heat the cathodes in the valves whilst the high voltage they needed was supplied by multi-celled zinc-carbon batteries.  Few homes had the facility to charge the accumulators, so shops selling electric appliances offered a charging service, adverts for this can be found in the small ads of the magazines.

In general, the classified ads in the county magazines are not much different from those found online today, they offer "facial rejuvenation", building services, garment alteration etc..  Private tutors still advertise in newsagent's windows, but they don't seek out "backward" children.

Having gone through my small collection of country magazines, for the sake of completeness I thumbed through a 1949 copy of "Men Only".  The is some surprising overlap in the content, the same cars and lawn mowers are advertised, the men are dressed in similar style, some of the women are wearing slightly less, but both are part of the same world.








Thursday, 7 July 2016

The early days of electricity in Hove (2)

This post is really my notes from researching the early days of electricity in Hove, it is probable that there will be corrections and revisions.  As with the previous post, the source is the log books of the power station of the Hove Electric Light Company from 24-Nov-1892 to 27-Sep-1894.  I have yet to find a floor plan of this site or an inventory of the equipment, but the log books give an insight into the nature of operation and it's economics.

One thing that stands out when the weekly generation data is plotted on a graph is the seasonal variation in the demand for electricity.  Whilst the log books make a couple references to small electric motors on customer's sites, most of the output is used in incandescent lamps (typically 33 watts) and arc lights which might draw 10 amps (roughly 1 unit per hour with a 110 volt supply).  In the winter of 93/94 generation amounted to roughly 2,500 units/week and then dropped off as summer approached.  So in the summer of 1894, output was falling even though more customers were being signed up.



It is not clear if this seasonality was factored into the economics of operation, but it is possible that a stoker was laid off during the summer.  In Sep-1894, wages accounted for just less than one third of the operating expenses.  It is not clear in the remarks if the boilers had mechanical stoking or relied on a man with a shovel.

The largest expense was coal and coke.  There is an inference in the log books that the preferred type was Welsh  Coal (20 - 27 shillings/ton), this has a high calorific value (marine engineers also liked it), but at times, possibly as an economy measure, alternative fuel was used such Northern Steam Coal (19 shillings/ton).  In the first few months of operation some coke was used, maybe this came from the local gas works. 

The logs don't say much about the type of machinery, but there is a reference to Davey-Paxman sets.  I'm guessing but these steam engines were probably similar to those used in mills and factories, these were relatively slow speed.  Often power was distributed around the factory with a system of shafts and each machine was connected to this by a belt drive.  There is also a mention of Willans engine, this was probably a high speed engine specially developed for the growing electricity industry, typically the dynamo was directly coupled to the steam engine's crank shaft.  Hopefully, I can find out more.



By modern standards, the boiler pressure was low, initially they operated at 140 p.s.i.  and later this was increased 160 p.s.i.. after inspection by the insurance company.  Steam locomotives in the 1950's were often working in the range 200 - 250 p.s.i. and modern steam power stations run at very high temperatures and pressures to maximise efficiency.  The steam would have been saturated and there is no reference to condensers.  Thus the efficiency was very low, a crude sum suggests that it was in the range 2 - 3%, that of modern coal power stations might be around 40%.  The log book states coal consumption as 10 pounds/unit of electricity generated.  Leaving the town hall arc-lamps burning all night would create extra work for the stoker and a noticeable increase in operating costs.  Maybe, because of the lack of condensers, they were not able to recover water from the exhausted steam as water consumption was several thousand gallons per week.

The station was equipped with storage in the form of some large lead acid batteries, the capacity of these was about 30 units (110 amp hours).  These appear to require regular maintenance as sometimes their consumables (plates, soda etc.) show up as a spke in the expenses.  The function of these is not given, but it is probable that the storage acted as a buffer for fluctuations in load and also to meet some or all of the overnight demand, this would allow the boiler fires to be banked up to save fuel.  During the summer months the average daily demand might be 100 - 200 units which peaked in the evening, thus the 30 units of storage could simplify operations.



Wednesday, 6 July 2016

The early days of electricity in Hove (1)

I learnt about the Hove Electric Lighting Co. Ltd. from a description of what seemed to be a small power station whilst reading Queenspark Book No. 36: "A Working Man".  After looking up the buildings in Cromwell Road in Hove in a Kelly's directory, I found the business name.  Not being able to find anything more, I decided to research it myself.  The East Sussex Records office has the first three log books of the power station and it is these that this and the next post are based on.

Ideally, I should hunt down all the available material and the write it up in a single post, so these posts are really my notes which at sometime in the future may get consolidated.  If anyone has already done something similar and better, I apologise.

In the last decade of the 19th century, many small electricity companies were established by entrepreneurs or by town councils.  I find them interesting because with some stretch of the imagination the municipal ones might be described as micro-grids under local democratic control with all their assets located in the community they serve.  This is in contrast to the situation today where power stations are often located on remote headlands and are managed in distant boardrooms.  There are technical, commercial and political reasons why this transition took place, but something might be learnt from the early history of the industry.

It seems that the power station started operation in the week ending 24-Nov-1892.  During that week it produced just 95.79 units (kwh?) but by the end of the second week this had risen to 435.3 units, after which the demand was determined by the seasons and the number of houses connected, during the first two years the peak generation was about 2,500 units/week in the December 93/January 94 period, it is probable that it would be much higher during the next winter.

At the start of operations there were just four houses connected to the grid, this suggests the bulk of the load was coming from street lighting and council premises.  There are several references in the logbooks to arc lights at the town hall either being left on or going out.  There were two forms of lighting in use, arc lamps which were capable of illuminating a large area and incandescent lamps, typically rated at 33 watts.  The downside of arc lamps was their high current drain, maybe 10 amps and the need for constant maintenance, in 1894 this required a full time person.  The supply was 110 volts DC, thus a 10 amp arc lamp was consuming a unit of electricity each hour, the generating efficiency was low with 10 lb of coal being required to generate a unit of electricity, thus leaving several arc lamps burning when they were not needed could significantly increase coal consumption.  Arc lamps are sometimes described as "carbons".


In just less than two years, the number of private houses connected to the grid rose from 4 to over 200.  Connecting a property to the electricity supply required investment both on the part of the electricity company who had to make cabling, distribution and metering points available and the householder who needed to install wiring and light fittings.  In the early 1920s, it cost about £30 to wire up a three bed room semi in the north of England for electric lighting.  Some of the first houses in Hove to be connected had more than 100 lamps, so the outlay would have been great, not only was there the cost of the electrical work but cost of redecorating after wires had been run through walls, floors and ceilings.  My own house was initially piped up for gas lighting, when electric cabling was installed, channels were cut into brickwork and wooden pads used to secure sockets and switches and there was a lot of "notching" of joists to run conduits under the floor.  The company inspected each property before connection, there is one reference to minor non-compliance that was accepted on the condition that remedial work was carried out "after the season".

The graph below shows the increase in the number of connection over a two year period.


What is more interesting is the nature of the connections.  I walked around most of the streets mentioned in the log books and it appears that connections can be split into two groups.  The first was retailers, I guess that installing electric lighting was seen as getting a competitive edge over one's rivals, much the same as air conditioning is today.  Electric lighting would create a better retail environment than gas lights could which were dirty and could fill an unventilated space with foul air (e.g. increase the level of carbon monoxide).  the operation of electric lighting is just flicking a switch and occasionally changing a burnt out bulb.  Gas mantles have to be individually lit and regularly cleaned.  The second group might be described as posh residences.  Posh is probably the correct word, the people who owned these houses would most likely have been on the port side outward and on the starboard side homewards when travelling to and from India, Singapore, Hong Kong, Australia or New Zealand.  The houses are big and would have required several servants to function.  In modern marketing language, these people were "early adopters" who were prepared to pay a high price, the cost of electricity might have been around 8d/unit (more than £1.00 in today's money).  None of the houses I walked past were the sort of place where craftsmen, teachers, clerks or shop assistants might have lived, it might be thirty or forty years before such cane home to an electric light switch.

The map below shows the streets mentioned in the log books, those marked red are predominantly residential whilst the blue ones are mainly retail.  Except in the shopping areas along Church Road and Western Road, there are only a few customers in each street, however, the mains for distribution would have been available for additional customers.


There appears to have been a ready market for electricity, as mains became available in a street, houses were soon connected to it.  There were a small number of disconnections for reasons not specified, but one reference suggested that electricity was becoming indispensable, a house was disconnected one day, but reconnected on the following one.

The data available does not show levels of household consumption, but it suggests that the average during the winter months was around 10 kwh/week and less than 5 kwh during the summer, this might put average household consumption in the range 200 - 500 kwh/year.  The current average in the UK is about 3,500 kwh/household/year.  The principal use of electricity was for lighting, but there are two references to electric motors, one is for a half horsepower one in a dairy 

Electricity was creating new types of job.  The dynamos in the power station were driven by reciprocating steam engines which at that time was a mature technology, but establishing safe and reliable distribution systems was a new challenge.  by the middle of 1894, there were four distinct groups of works in the company, about half a dozen people worked in the power station, two were involved in connecting properties to the mains, two more maintaining those mains and two going round testing and reading meters.