The Blog - Don't Sweat the Big Stuff

So much of the debate on energy focuses on the big stuff, nuclear power stations, wind farms and feed-in tariffs to name but three.  A planning application for a wind turbine will soon get a mention in the media, some local residents will opose it as a blot on the landscape and some environmentalists will declare it as an important step towards a carbon neutral economy.  Wall warts get little attention.  Wall warts are the little black plastic boxes we plug into mains sockets to provide the small amount of low voltage DC which provide the excitement from powering christmas tree lights, watching football on an iPhone and listening to the radio.

The average home has a lot of wall warts.  These things are usually part of an extended family which includes laptop power supplies and the internal power electronics of settop boxes.  As with most things there are good and bad wall warts.  A bad wall wart is warm to the touch, this means its dissapating energy in the form of heat whilst a good wall wart remains at room temperature.

Recently, the DAB radio in the kitchen lost the will to live and merged Classic FM and Radio 4, after several weeks someone noticed and a new one appeared.  Some years back, I purchased a plug in power meter which over a period of a week gives a reasonable estimate of the power a given bit of equipment uses.  The old DAB radio consumed something like 30 kwh per year whilst feeding my wife's addiction to the Archers, the new one could reduce this to 5 kwh, a saving of 25 kwh/year.

A common measure used to describe the contribution of wind farms to the energy economy is the number of households which can be supplied, the number used to estimate this is around 4,700 kwh/year.  Thus if 188 housefhold reduced their consumption by 25 kwh/year, this is the equivalent of reducing the demand for electricity by one household.  I like comparing conservation with generation.  An industrial wind turbine rated at around 1.5 MW, produces approximately 3,000,000 kwh/year, thus if 120,000 households reduce their consumption by 25 kwh/year, this the equivalent of installing a single wind turbine.  A lot of people doing small things can make a big difference.

In many homes electricity accounts for less than than 20% of the energy consumed, the rest is consumed by a single device, the gas boiler (why are they called boilers, if they do boil then something has gone badly wrong!).  Our own example costs something like £1/hour to run and as result it does not run very often.  Despite being an engineer I only learnt about domestic heating late in life when faced with a choice of cutting the gas bill or drinking less.  We got a quick win by replacing the hot water system's misplaced faith in gravity with a circulating pump.  It used to take 90 minutes to get a luke warm bath, we now get a hot one in 20 minutes.  The next step will be to zone the central heating.  Our heating is on or off, we either heat the whole house or none of it.  Apart from one of my sons who is nocturnal, most of the day we're downstairs, and most of the night we're upstairs in bed.  We don't need to heat the upstairs part of the house during the day (more on this exciting topic in a future blog).

The problem with conservation is that it is just not sexy.  When the energy minister declares a wind farm to be operational, there's almost certainly going to be a picture of him wearing a hard hat standing in front of a 100 metre turbine.  Few politicians are rushing to pose next to a wall wart.

Any interested reseach body with funds to spare and looking for a project might want to try this.  Give 1,000 homes a plug in power meter (cost approx. £20) and see what energy savings they can make over a three month period.  Most importantly, put the project together in such a way that children can participate safely.  I don't know what the outcome would be, but the results could widen and inform the debate.