Workers Playtime

October 25, 2006

We’ve moved back home to dojo

Filed under: Uncategorized — plague @ 12:36 pm

keep up to date with this blog at it’s new home


October 20, 2006

Turlough Bill

Filed under: battery, inverter, night-saver, power, squat — plague @ 1:35 pm

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.

October 19, 2006

Power to the people

Filed under: alternative energy, power, solar, wind power — plague @ 1:00 pm

There seems to be a bit of a buzz about alternative power sources lately, with the Al Gore film, the power of one campaign and B&Q selling wind generators and solar panels.

This has got to be good news for the environment, with energy being created without the use of carbon based fuels, but are these new domestic power sources going to save us on our ever increasing fuel bills?

When you first look at the savings the 1Kilowatt wind turbine from B&Q will give it’s about one megawatt (1,000,000 watts) of power a year. At roughly 15 cent per kilowatt this is only 150 euro per year in savings. With the cost of the wind turbine at 2250 euros it will take 15 years to pay for itself. With a one year guarantee and a 10 year life expectancy I won’t be rushing out to get one of these.

Alternatively I’ve come up with better solution, first cut down on all the wastage of electricity in your home. Use CFL bulbs where lights are needed on for long periods, use PIR and audio switching to turn on and off lights, and switch to night rate (half price) electricity and do heavy usage stuff like washing machine/dish washer at night.

Another tip is to get an intelliplug (27 euro at maplin) that monitors usage on a master appliance like TV or Computer and when the appliance is turned off it shuts down power to the other peripherals that are in use or in standby. I did some calculations on my own nonstandard TV system, it has 8 peripherals

TV (master)

  • FTA satellite
  • FTV satellite
  • Analogue satellite
  • Stereo amplifier
  • DVD recorder
  • FM tuner
  • Antenna amplifier
  • CD player

these all added up to 44 watts in standby, when the glass doors on the cabinet were opened the heat of this is noticed, and the appliances are warm to touch. Now when the TV is put in standby or turned off all the other appliances shut down.

This 44 watts per hour works out at 880 watts over 20 hours of standby, over a 61 day bill this goes up to 53,680 watts at 15 cent per watt that’s 8.50 euro per bill, or 51 euro per year. So this device can pay for itself in nearly six months and after that it’s saving you money and the environment.

Our kitchen is tends to be a dark place as there’s no window for light, so it is lit by 3 x 50 watt downlighters. The plan is to replace the single switch with a PIR/Audio switch that turns on after motion or audio is detected and time out after X minutes of inactivity. I’ll keep the blog posted on how this project goes.

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