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Micro heaters cut 87% off my electric heat bill

richsoil.com

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

#251

Earlier quoted context omitted.

Don't use boiling water with hot water bottles; the ones you can buy have warnings about this (it can damage them). Just use hot water from the tap (which hopefully should be more efficiently heated than however you boil water as well). Don't worry about energy consumption; it's negligible for the hot water bottle, and for the electric blanket as well, especially compared to keeping your house heat up high at night.…

If the bottles are dedicated to this use, it's fine. The soft-walled ones may discolour slightly.

It probably depends on the water bottle.

I put boiling water into a fairly thin-walled rubber one, and it sprang a leak a few minutes later, so I'm more careful now.

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

#252
post #216

Earlier quoted context omitted.

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 proba…

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 l…

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

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

#253
post #210

Earlier quoted context omitted.

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 th…

Yeah my second sentence was a non sequitur, but my point was: you can only do a little with solar/water heating. Yes heating a pool is one of those things, but that's a very niche application. This thread is about heating a house, or at least about being comfortable in one, and solar/water is just not a viable technology for that in the vast majority of cases.

Oh... you said "PV" in both sentences, which is specifically converting light to electricity; that's what threw me.

For heating a house with solar (not PV) -- it would depend on insulation level, I'd imagine. I do know people who use it for "most of the time" water heating, with good results.

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

#254

Earlier quoted context omitted.

...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…

"the ideal structure is not supposed to exchange air with the outside" No, the ideal structure should minimize heat loss from air exchange . I'm not fully up on my air exchange rates, but it's fairly typical for ranges to be in the 4-20 range, that is, the interior air is exchanged with the exterior 4-20x per hour. In my Thorsten Chlupp references elsewhere you'll find he makes extensive references to heat exchangers…

+this.

Another way of putting it: A well-designed structure should minimize random, unintentional air exchange, but provide sufficient deliberately-engineered ventilation to keep the air and people happy. For efficiency, that ventilation should go through a heat recovery ventilator (HRV) or energy recovery ventilator (ERV) as appropriate to the climate and budget. (An energy recovery ventilator also exchanges moisture).

Beyond Chlupp, Lstiburek is a great engineer and writer on these topics.

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

#255

Earlier quoted context omitted.

Putting in heat over a short time, to recover from low temperatures, is different to putting in heat over an extended period. If your heater has very low efficiency at high heat output then it seems highly possible that extended low output could be better. It's a financial efficiency we're talking about primarily when people are looking to more efficiently heat their house. If you're heating with electric for example…

Virtually all thermostat-controlled heating systems I've seen don't have different output levels, but are just on or off. So poor efficiency at high output wouldn't come into play. The rest is possible, but I'd file using expensive electricity instead of cheap electricity under the thermostat not doing a very good job, or more precisely the person setting it up not doing a good job of setting it up to run more cheapl…

Gas fired combi boilers (with centrally heated [pumped] cycling water) are pretty much the default in the UK. I've never seen one that didn't have output temp adjustments. I'd imagine that set highest (which should reach thermostat set target temp fastest) would produce greatest flue losses but I'm speculating there.

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

#256

I'm sorry, I'm sure this idea/post is valid, but damnit if this isn't exactly what the recent HBO show "Silicon Valley" lampooned in the finale. I cannot stop laughing.

it's not exactly the same, but close enough to be cuttingly funny.

https://www.youtube.com/watch?v=7WvDHKKsCL4

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

#257

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…

I have been told by multiple HVAC professionals recently that one should keep their fan on their system always running. They have in fact adopted this practice at our offices and it greatly help with keeping temperatures in consistent from room to room. The arguments they provided for this were: [1] Constant air flow creates more consistent temperatures (less highs and lows from interior to exterior or floor to floor…

I run the circ fan all the time as well, but the bearings on the motor do have a limited lifetime. Ask me how I know this.

A new motor will cost hundreds of dollars, more so if the blower and fan cage are a single assembly. You'll need to amortize that cost into your comfort level.

It will also quit at the least convenient time, following a combination of Tuttle's and Murphy's Laws. Again, ask me how I know this.

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

#258

Earlier quoted context omitted.

Virtually all thermostat-controlled heating systems I've seen don't have different output levels, but are just on or off. So poor efficiency at high output wouldn't come into play. The rest is possible, but I'd file using expensive electricity instead of cheap electricity under the thermostat not doing a very good job, or more precisely the person setting it up not doing a good job of setting it up to run more cheapl…

Gas fired combi boilers (with centrally heated [pumped] cycling water) are pretty much the default in the UK. I've never seen one that didn't have output temp adjustments. I'd imagine that set highest (which should reach thermostat set target temp fastest) would produce greatest flue losses but I'm speculating there.

I meant controlled by the thermostat. I'm sure you can adjust it manually, but in normal operation, it's cycling between on and off, and nothing more. Output level when heating your house from 50F to 70F is the same as heating your house from 69F to 70F, it just runs longer.

I'm sure there are exceptions to this somewhere, but it doesn't seem common. Thermostats don't typically have a way to command anything besides on and off.

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

#259

>In June of 2010 I moved to a place in Montana with only electric heat. Living that far north and depending on one heat source is crazy! Think about the power going out when its -30 out... or if you used gas, running out or having your furnace break down. (Not to mention electric is usually the most expensive way to heat). Most houses where I live have 2 or 3 heat sources. I have wood, LP and electric...

I lived in Minnesota and had only electric heat. Most other houses have only gas heat, and it usually requires electricity to run. Luckily the electricity is pretty reliable. If you do lose heat, the solution is generally to use blankets outdoor gear until it is fixed. But this has never happened in my 20 or so years of living there.

>I lived in Minnesota and had only electric heat.

Did you live in town, or in the country?

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

#260
post #111

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…

His article on CFLs ( http://www.richsoil.com/CFL-fluorescent-light-bulbs.jsp ) is very cringe-worthy as well. As part of his argument, he references a report he heard of claiming that kids gained 20 IQ points by switching back to incandescent bulbs. Seriously.

His article on Diatomaceous earth is mind boggling, advocating cooking with it http://www.richsoil.com/diatomaceous-earth.jsp

wikipedia: "In order to be effective as an insecticide, diatomaceous earth must be uncalcinated (i.e., it must not be heat-treated prior to application)[13] and have a mean particle size below about 12 µm (i.e., food-grade – see below)"

Its used occasionally for deworming people and considered a low risk insecticide. Just because you can eat it and it has some benefits in use cases doesn't mean you should consume as much as you can. Its the classic vitamin snake-oils sales pitch, "X is good for you thus more of X must be better for you"

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