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Micro heaters cut 87% off my electric heat bill

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Re: Micro heaters cut 87% off my electric heat bill

#121

Post by [deleted] »

XorNot wrote: post #97
jlebar wrote: post #79

Earlier quoted context omitted.

> I don't know how people's desires can be "wasteful". In a world where people paid for the true cost of their energy use, this argument might fly. But in most of the world today, this isn't the case, not by a long shot. If you heated to "summer inside the house" and bought high-quality carbon offsets corresponding to your increased energy use, I think most people wouldn't call that "wasteful". "Warm" might be the ad…

In a world where people paid the true cost of their energy usage, there wouldn't be an absolute deluge of houses built by terrible contractors with terrible insulation on the market, where the biggest, best and cheapest energy saving measures weren't put in when the house was built. I want summer in my house during the winter. This should be an explicit goal, because you can't get there by just cranking up the heat s…

[deleted]

Re: Micro heaters cut 87% off my electric heat bill

#122

Post by roel_v »

ams6110 wrote: post #91
mangecoeur wrote: post #28

Earlier quoted context omitted.

Wrong. Does plenty to save energy. Reasons: - for half the year, you don't heat but you still light, so you automatically gain savings for that whole period. (also if you have air conditioning, in summer you heat the house with lights then have to cool the air again) - Lights are on the ceiling. Hot air rises. Therefore heat coming from lights does almost nothing to improve your thermal comfort. - If you are heating…

What's the energy cost of making a CFL bulb vs. an incandescent? Also since in practice they don't last a lot longer, and are annoyingly dim for the first few minutes, and are considered an hazardous waste when you need to dispose of them, why does it make sense to replace a $0.50 bulb that has none of those issues with a $5.00 bulb that does?

CFL is crap, use LED lights. Last 20x longer with 1/20th the energy use. Replacing incandescent with CFL is a wash, replacing them with LED is a no-brainer.

Re: Micro heaters cut 87% off my electric heat bill

#123

Post by roel_v »

WalterBright wrote: post #73
bluthru wrote: post #29

Earlier quoted context omitted.

Of course it does. Heating up a hole in your ceiling does not efficiently warm the occupant. You want to introduce heat low and near occupants. Also, changing out multiple incandescents means more manufacturing, more truck deliveries to the store, more manufacturing, etc. vs. using a single LED bulb for two decades. If you live in coal country, then you definitely want to reduce your electrical load and instead rely…

Two decades? My experience is LED bulbs last about a year.

The el cheapo ones, yes. There are expected lifetimes on LED bulbs ranging from 2000 (similar to incandescent) to 50000 hours. Of course the 50k ones are (much) more expensive.

Re: Micro heaters cut 87% off my electric heat bill

#124

Post by snicker »

jwmerrill wrote: post #114
dredmorbius wrote: post #67

OK, Paul Wheaton simply doesn't know what he's talking about: "I think that this does produce some savings, but not as much as you might think. If you set your thermostat to a constant 70, the heater works a little at a time throughout the day. If you drop it to 50 at night or in the middle of the day, the heater stops working, but then when the time comes to warm the house again, the heater has to work at full power…

Your theoretical analysis misses an important physical fact: houses are able to exchange air with the outside world, not just heat. As you heat a normal room, it will expel air in order to maintain constant pressure, and similarly, as you allow a room to cool, outside air will enter again to keep the pressure constant. There was an article about this in the American Journal of Physics [1, 2] a couple years back, and…

...but the ideal structure is not supposed to exchange air with the outside particularly because of this. That is why windows and doors have seals on them. I'm no mechanical engineer, but I've worked with enough of them in my career to understand that their goal is usually keeping a structure tightly sealed when ingress/egress paths are closed (of course opening windows/doors is a choice of the occupant, which if your striving to reduce heat loss/gain... you shouldn't do)

Re: Micro heaters cut 87% off my electric heat bill

#125

Post by jtheory »

jebblue wrote: post #117

I was really caught up in this story and the effort involved until ... "I wonder if these techniques caught on, could this reduce or eliminate US war for oil?" and then "If I wrote this article 20 years ago might we have never gone to war with Iraq?". Iraq was _not_, repeat, NOT, N O T, about oil. Iraq was about stability, about a nut case leader who terrorized and killed his own people, who let his sons terrorize pe…

Voted down, then responding in case you don't know why: this is a discussion about micro-heaters.

Yes, it's a bit disagreeable to run across even minor, aside comments that disagree with something you believe strongly, but please just deal with that on your own time.

Because of course your comment will be unpleasant for people to read who feel just as passionately that you're wrong, and some of them may be compelled to post wall-o-text comments here to rebut your claims.

Here, in this discussion about micro-heaters.

Re: Micro heaters cut 87% off my electric heat bill

#126

Post by jwmerrill »

snicker wrote: post #124
jwmerrill wrote: post #114

Earlier quoted context omitted.

Your theoretical analysis misses an important physical fact: houses are able to exchange air with the outside world, not just heat. As you heat a normal room, it will expel air in order to maintain constant pressure, and similarly, as you allow a room to cool, outside air will enter again to keep the pressure constant. There was an article about this in the American Journal of Physics [1, 2] a couple years back, and…

...but the ideal structure is not supposed to exchange air with the outside particularly because of this. That is why windows and doors have seals on them. I'm no mechanical engineer, but I've worked with enough of them in my career to understand that their goal is usually keeping a structure tightly sealed when ingress/egress paths are closed (of course opening windows/doors is a choice of the occupant, which if you…

An ideal structure should minimize convection, but rooms for people really can't be allowed to undergo large changes in temperature without exchanging air with the outside environment, because that would imply a large change in pressure.

A 10 percent increase over atmospheric pressure might not seem like that much, but it's enough to notice, and would probably be uncomfortable. It's like being under 1 meter of water. It's also enough to break large windows.

Re: Micro heaters cut 87% off my electric heat bill

#127

Post by [deleted] »

jebblue wrote: post #117

I was really caught up in this story and the effort involved until ... "I wonder if these techniques caught on, could this reduce or eliminate US war for oil?" and then "If I wrote this article 20 years ago might we have never gone to war with Iraq?". Iraq was _not_, repeat, NOT, N O T, about oil. Iraq was about stability, about a nut case leader who terrorized and killed his own people, who let his sons terrorize pe…

[deleted]

Re: Micro heaters cut 87% off my electric heat bill

#128

Post by jtheory »

roel_v wrote: post #120
willholloway wrote: post #63

Energy is abundant, there is no need to shiver in the cold. Solar forced warm air is inexpensive, simple technology that is very underutilized. Solar photovoltaics get all the attention, but solar warm air/water is less expensive and simple to manufacture. http://sunmatesolarpanels.com/content/view/2/31/

But you can't power a computer on PV. I don't think anyone who knows something about energy efficient heating suggests PV to warm a house electrically, it's too inefficient.

Not my comment you're responding to, but it's not talking about PV for heating (that'd be kind of ridiculous, honestly).

Systems for heating water/air using solar can be quite inexpensive as well; converting light to heat is rather easier than converting it to electricity.

E.g., I've seen cheap pool-heating systems that just pump the water through wide flattened black pipes exposed to the sun and send it back into the pool. Voila, solar heating!

Re: Micro heaters cut 87% off my electric heat bill

#129

Post by davepage »

personZ wrote: post #100
ams6110 wrote: post #85

Earlier quoted context omitted.

I agree with all your theory. I thought the same thing. Then I went out and bought a programable thermostat, set it quite low overnight and during the day, and warmer from 5-8 AM and 5-8 PM. My heating bill was higher than just maintaining 68-70 all the time. And that's not even counting the $100 I spent on the thermostat (now on a shelf in the garage, I put the old manual one back in its place).

From a thermal energy perspective this simply isn't possible. However , some systems do lead to this because of flaws in the the implementation. My ground heat pump, for instance, has a backup electric heat system that it will automatically, and unavoidably, utilize if it hasn't reached the target temperature within a set, relatively short period of time. So in my very well insulated home I do indeed see significant…

A well designed thermostat should control the auxiliary and emergency heat when installed properly. http://www.behvac.com/troubleshooter41.htm http://support.nest.com/article/What-s-Emergency-Heat-and-do...
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