Most wasteful electronic gadget on the market. / General Chatting / Forums

Forums

4hv.org :: Forums :: General Chatting

« Previous topic | Next topic »

Most wasteful electronic gadget on the market.

previous 1 2 3 4 next

Move Thread

LAN_403

Steve Conner

Wed Nov 11 2009, 10:15AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Dago wrote ...

With my logic (assuming that you need heating in your house to keep the temperature constant) all the power "wasted" by electronics appliances will just reduce the amount of heating needed. This does not apply to hot areas/summer where you dont need heating for your house.

This is true. Unfortunately it's still not optimal, because electric heating has only one-third the Second Law efficiency of a fuel like gas. The reason being that the power station only turns about one-third of the fuel burnt into electricity.

So, if you burnt the fuel directly in a heater in your home, you could have three times the heat for the same carbon footprint. (Not to mention the same price, because electricity tends to be about three times the price of gas.)

And conversely, if you insisted on heating your home with electricity, you could buy a heat pump and use it to pump three units of heat into your home for every unit of electricity it consumed.

I'm guilty too, my living room has a large tube amp where the fireplace should be :)

White LED backlights are great. I just finished working on a handheld instrument with a VGA colour screen. When we started the design, we couldn't find a white LED screen and had to make do with CCFL. Later we found one, and it gave slightly higher brightness, while increasing the battery life from 5.5 hours to over 8. The backlight was always the most power-hungry subsystem of the whole instrument.

The European Union are in the process of banning incandescent light bulbs. This has already happened in Australia, and Rod Elliott has been incandescent (

) with rage about it for a while.

Nicko

Wed Nov 11 2009, 10:48AM

Registered Member #1334 Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615

Steve McConner wrote ...

...conversely, if you insisted on heating your home with electricity, you could buy a heat pump and use it to pump three units of heat into your home for every unit of electricity it consumed.

I installed an IVT Greenline 3phase heat pump in our house when I rebuilt it during 2005. We now have a good sized, carbon-neutralish, house (over 4000 sq ft) with the very latest insulation and (now re-)built as a thermal store.
With 3 kids & two adults doing lots of sports (lots of washing, lots of showers), our total lighting, heating & HW bill is about GBP 1,200 pa. The heat pump is the smaller box on the left - the larger box is a 300ltr thermal store that the heat pump can refill every hour.

I reckon the heat pump paid for itself in just over 3 years... however, every weekend it use a couple of KWh to raise the water temp from its standard 50/55C to 70C for an hour to kill any legionella that might be lurking in the pipework..

Steve McConner wrote ...

I'm guilty too, my living room has a large tube amp where the fireplace should be :)

In my case a valve amp (Morgan Jones design) and a Perreaux huge 19" racked class A FET amp (idles at about 60C) keep the room toasty!

ConKbot of Doom

Tue Nov 17 2009, 02:00PM

Registered Member #509 Joined: Sat Feb 10 2007, 07:02AM
Location:
Posts: 329

I think that waste water heat recovery is something that is overlooked way too much. For showers, for example, its a simple 4-6 foot section of copper drain pipe (presumably place horizontally) with water supply line wrapped around it. You feed the cold water into it, and it is heated by the drain water, so you need less hot water to get your ideal showering temperature. Unfortunately copper has gotten quite pricy lately, but its not just energy savings, you can take longer showers on a smaller tanked water heater or for an on demand system, use one with a smaller deltaT at a given flow. Has anyone actually run any numbers on these to see what the payoff time typically can run?

Bjørn

Tue Nov 17 2009, 02:43PM

Registered Member #27 Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058

This example that is not made very efficiently extracts 7 kW from the hot water. http://www.sondred.info/varmegjenvinner.htm I am sure double that is no problem. There is a link somewhere to some students that got over 80% recovery.

ConKbot of Doom

Tue Nov 17 2009, 04:05PM

Registered Member #509 Joined: Sat Feb 10 2007, 07:02AM
Location:
Posts: 329

BjÃ¸rn wrote ...

This example that is not made very efficiently extracts 7 kW from the hot water. http://www.sondred.info/varmegjenvinner.htm I am sure double that is no problem. There is a link somewhere to some students that got over 80% recovery.

Ok, so assuming $.08/kwh (on the cheap side I believe ) and Ive seen some heat exchangers for sale at $700 (pricy, I'd be willing to bet someone handy could make one for cheaper...)
thats 8750Kwh that need to be recoverd to break even. Using 7kw that they were pulling out, would be 1250 hours of run time. or ~3.5 years assuming an hour of usage per day (family of 3, 20 minute showers each, daily) More costly electricty, cheaper construction, more efficient heat exchanger, teenagers, all could make it pay off quicker.

$.16/Kwh, a $400 heat exhchanger, and 40 minutes/person/day (tie the bathroom sink in also, get heat from stuff such as dad shaving...) and still recovering only 7 kw would make for a 6 month break even point (!)

but this is off topic for wasteful electronic gadgets... unless you want to count electric water heaters

I'd have to say, that while most of us dont like hearing it, PCs eat up a good bit of electricity idling. Especially gaming PC video cards. And if youre not letting the PC idle, thats an even bigger draw. I used to run folding @ home at college, (folding arms race against other nerds :) ) and I had a dual core desktop, my laptop, and my 'backup' PC (down time wasnt acceptable, so I brought my old set of PC components, and when the folding arms race started, I got a case in for it. Put a wireless NIC in it, and the only thing going to the box was a power cable ) Yeah... that winter we regulated the temperature of the room by how far open the window was open behind the box fan.

Arcstarter

Wed Nov 18 2009, 12:33AM

Registered Member #1225 Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253

What do ya know. Just a few days ago, my dad bought my mother a some 10 inch picture frame... XD. That thing's gotta consume some electricity.

Also, it is finally getting as low as 60 degrees normally outside. The house is 70 degrees even when it was 38 degrees last night, and the air conditioner was running. I blame inefficient electronic things...

I have noticed, my room is always quite hot. It is because i leave the door closed (air does not circulate) and i sometimes leave the computer on.

Nik

Thu Nov 19 2009, 02:18AM

Registered Member #53 Joined: Thu Feb 09 2006, 04:31AM
Location: Ontario, Canada
Posts: 638

The biggest power waster in my house is the new energy star dryer and the new microwave. The old clothes dryer took about 30-40min to dry a nik sized load of laundry. The new low consumption one takes about 90min and the clothes still come out damp. Our old 1970s beast of a microwave could explode my pizza pockets about 10 seconds faster then the box said I should leave them in for, the new "more efficient one" takes about 30 seconds longer. Maybe its just me as a special case but I liked the old power hogs because they were faster. Now it takes longer or more smaller loads/meals to get the same amount of laundry/eating accomplished.

On a related note there was an article on /. that pointed out most CFL bulbs have terrible power factor of around 0.4 (that's around 66 degrees lagging). Now if the bulb is labeled 100W equivalent (26W bulb). With a 26W true power and PF of .4 that means it actually 65VA. So your hydro company has to supply (120v mains) 541ma instead of 217ma that you would assume from seeing the 26W label. 324ma doesn't seem like a big problem but when every one is forced to switch to CFL more then half of the current supplied for lighting goes into the reactive load of the bulb and essentially does nothing. That is a big problem and a BIG waste of money.

/hoards his incandescent bulbs, they look nicer

Proud Mary

Thu Nov 19 2009, 02:49AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

I should say the television. It seems often that whenever a toilet is flushed in the White House, then lies and filth belch out of the television into my living room.

Like many others, I have disabled the RF input circuit of my television, so as to re-define it as a monitor, and thus exempt me from paying Â£140 licence fees a year to be disinformed by propagandists in my own home. In Britain today, The Lie is no longer a simple moral category, but has become the central pillar of the State.

The idea that we should actually pay to be lied to is typical of the moral-financial climate in Britain today, but the waste can be readily be put an end to by switching it off, or simply throwing it out to be recycled.

GeordieBoy

Thu Nov 19 2009, 10:06AM

Registered Member #1232 Joined: Wed Jan 16 2008, 10:53PM
Location: Doon tha Toon!
Posts: 881

>....but when every one is forced to switch to CFL more then half of the current supplied for lighting goes into the reactive load of the bulb and essentially does nothing.

I'm with you and Rod Elliot 100% on this one! "Energy Efficient" bulbs are horrible things...

-Richie,

Proud Mary

Thu Nov 19 2009, 01:58PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

GeordieBoy wrote ...

>....but when every one is forced to switch to CFL more then half of the current supplied for lighting goes into the reactive load of the bulb and essentially does nothing.

I'm with you and Rod Elliot 100% on this one! "Energy Efficient" bulbs are horrible things...

-Richie,

Two points here Richie (no, I said 'points' not 'pints'

)

In a temperate climate such as ours here in Northern Europe, where our homes needs must be heated for three months a year, the resistive heat ostensibly 'wasted' by incandescent bulbs actually serves as low-level background heating.

But I do have good words to say for 'energy efficient' bulbs nonetheless: I have 300W 'equivalent' artificial daylight bulbs in my kitchen, bedroom, bathroom, and parlour, and find them of help in mitigating seasonal affective disorder. What's more, they are invaluable in finding dropped screws, something for which I have an especial talent. It seems very brilliant to those habituated to dim incandescent lighting, but is no more than the same lux of a bright summer's day.

I have one of those cute little direct vision spectroscopes I carry around in my handbag/US: purse, and it's interesting to see how very few colour bands there actually are in what is claimed as 'artificial daylight'

Stella

previous 1 2 3 4 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob