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Comment by nostromo | Hacker News Reader

People should check out WattVision. It's a little device that attaches to your electrical meter so you can monitor your electrical usage.

What I've found is that almost all of our home's electrical usage comes from heating (heaters, clothes dryers, and hot water).

Everything else is almost a rounding error. For example: I saw almost no change when we switched from incandescents to LED lighting (even in the summer when we're not heating the house) but I saw a large change with efficient shower heads and washing clothes on cold.

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Yup, if you're heating your house incandescents just lessen heating load.

However, if you're cooling your house incandescents are a triple whammy as AC isn't nearly as efficient as heating.

Incandescents heat the room at the ceiling, which I would imagine significantly reduces their effective efficiency relative to a well placed electric heater. Also, of course, incandescents have the same poor system efficiency as other electric heaters, compared to burning the fuel for heat in your house.

Totally heating dominate energy use. I'm rather disturb to hear people pay much attention to so call "phantom power" from idle electronics and adapters. Adapters plugged in the socket do not consume measurable power. Wifi router uses about a few watts. The worst offender is a set-top box that uses 18W irrespective of power on or off. It is piece of crap anyway so I unplugged it. All the electronics in the house probably use less power in a day compare to running a 1500W heater for 15 minutes.

Not really. It used to be true in the 1970s; but today appliances consume roughly about the same as space heating, despite decades of energy efficiency improvements --and the culprit is, you guessed it, the rise of consumer electronics [1,2].

And it's not just standby-mode "phantom consumption", as the EPA used to think. Today there are more devices with larger, sharper screens and hungrier batteries to charge, all left on for longer than ever before [2]. And it all adds up.

[1] http://www.eia.gov/consumption/residential/reports/2009/elec...

[2] http://www.energystar.gov/ia/partners/prod_development/downl...

Air conditioning. TV/gadget increases are dwarfed by savings in fridges, lighting, washers etc.

Fortunately I have natural gas for heating and hot water. Much cheaper than electric heat, but the local gas utility is still charging me about $12/MMbtu, which is about 3x the Henry Hub spot price.

But electronics is not nearly as benign as you suggest, it depends on your lifestyle. E.g. I have 4 TiVo boxes running 24x7. Each draws about 40W. In my area 1W works out to about $1/yr. So my TiVo boxes cost me $160/yr just in electricity.

I also believe that LED lighting saves money. In our family room I used to have a 75W light bulb on for at least 12 hrs/day. That's $37/yr for just a single bulb. I replaced it with an 11W Philips LED. It's now costing me $5.50/yr. That's an over $30/yr savings on a single bulb. The same savings applies anywhere light bulbs are on for a long time.

I carefully measured everything in my household. Nothing come close to a space heater. Most small electronics use negligible amount of power. We should not need to pay any attention to them.

http://tungwaiyip.info/blog/2011/12/24/home_power_usage

There are probably a separate category of problematic electronics that really sucks power. I was offended to find my set-top box suck 18W. I am doubly offended by your array of Tivo boxes. For 40W, my laptop will be doing computation intensive task with the fan running loudly. My mac mini consume only 11W when idle. A big huge TV would use power. I only have a 32" TV and I use it only a few hours a day at most anyway.

This cold winter in Chicago I tried an experiment where during the day I just heated one room with an electric space heater (a Vornado) and let the rest of the house get to 50 F. It ended up saving me exactly $1 because turns out electricity is $$$ and I discontinued the effort.

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