Turlough Bill

Back in 1987 I was one of the few that got a job that year and even better it was an apprenticeship in a career that I had an interest in, Electrician. Like many other workers in the Inchicore works I passed the time learning my trade and day dreaming, the whole place seemed to be on some sort of a permanent “Go Slow”, i suppose when there’s not to many jobs out there, the collective mind set was no to finish all the work too quickly.

Many of my daydreams would take the form of inventions, and like all good inventions they are born out of necessity or laziness. This particular invention was sparked by the common usage of batteries in my flat at the time because we didn’t have mains electricity because Monze or Terry didn’t pay the bill. The flat had two battery banks one12 volt for the music system and one 24 volt for lighting the three rooms. Our problem was that we didn’t have mains electricity to charge these battery banks so an army of punks that descended on our flat (they thought it was a squat) each night would occasionally bring along a flashing road lamp they’d borrowed from a nearby road works, which we’d add to the battery bank.

Now on to the practical uses of batteries in houses, in the flat we bypassed the transformer in the music center to let it run straight off 12 volt but this is not practicable with most mains equipment. What needs to be done is to invert the voltage up to 220 volt AC from 12DC, this is like normal transformers that take 220 V AC down to 12v Dc but in reverse and a little trickier as the dc has to be phased into a sinus AC to be transformed up to 220. Thankfully there’s a single box called an inverter that will do this job.

So in a nutshell you take standard 220 mains electricity you charge a 12 volt battery bank with a battery charger and invert the power back up to 220 with an inverter. But you might at this point say whats the point in doing this ?

• There’ll be losses on the way down to 12 volt
• There’ll be losses on the way back up-to 220 volt
• The mains is reliable enough so I need a UPS solution
• Why pay 700 euro for a system like this

The Best reason I can see for doing this is that if all the charging is done at night and you have a night rate meter you can avail of half price electricity 24 hours a day. Now, just to put things straight your new electricity bills won’t be cut exactly in half, there is an extra cost of the night rate standing charge this works out at:

• Urban domestic (storage heating) 6.50 euro per year
• Urban domestic Night-saver 49 euro per year
• Rural domectic Night-saver 94 euro per year

now if you already have the Urban Domestic (storage heating) it would be easy to tap the power from the system, and not tell the ESB that you’re not using this for heating otherwise go legitimate and get a night-saver account.

So with the above system you could suck power from the grid at less than half rate between 23:00 and 8:00 UTC (watch out in the summer the hour shifts) put it into your battery bank and pull it back out during the daytime

So how many batteries ?
lets say you have a bill of 150 euros a bill (two months) that’s about 1000 units or one megawatt so divide it by 60 days 1000/60 = 17 , so we have a total usage of 17 units a day, but about 5 of them come from night usage so we won’t bother putting those units into the batteries. So we need 12,000 watts of power in our battery bank, so 12,000 / 12 = 1000 amps, so 3 * 350Ah batteries or 4 * 270Ah batteries should do it.

Now what about the morals of doing this? are we stealing from the electricty company? I don’t think so, I think that all we are doing is replicating the ESB’s Turlough Hill on a small scale, 25,000 of these battery units would equal one Turlough Hill. At todays cost 25,000 of these units would cost 19 million euros as opposed to the 1968 cost of 20 million pounds for Turlough hill.

At a cost of about 750 euros for a system like this, it could save you about 360 euro off a bill of 900 euro a year, paying for itself in just under two years.