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We will be installing electric heat, probably baseboard since it is cheapest and will not be on much, and welcome opinions on the pros and cons of: oil- or water-filled, heavy cast aluminum, heavy steel (all said to be quieter and to produce less temperature swings) versus aluminum fins (also found on the oil-filled). How noisy are the noisiest model and how much does the temperature actually swing. Then do we really need wall thermostats or will the cheaper type do, that is installed in the heater. Line- or low-voltage? (We already have to put in 24-volt relays to qualify for Detroit Edison's 1/2 price electric heating rate). Please share your experience with baseboard heaters. Also, for bathroom heat is it better to have convection, or wall-or ceiling-mounted radiant (glowing element), or fan-forced heat? Or cables in the floor (warm feet) or ceiling (dry ceiling)?
61 responses total.
For the bathroom I'd suggest a heated floor. That's what they use in Norway, and it's quite nice. The room you're most likely to have bare feet in...
Except that the floor will heat up slowly and the idea is to be able to heat the room up quickly before taking a shower. How long does it take for the floor itself to start feeling warm, and how long for the air temperature to go up 5 degrees after turning on floor heat (Klaus?). I already have experience with a bathroom that takes 2 hours to heat (from 45 to 55, in the basement). Perhaps a combination of a little floor heat, and a ceiling-mouted fan forced heater? (No wall space available in one bathroom.)
If you're looking for quickie-heat in the bathroom and have no wall space down low, i'd say go for the ceiling-mounted radient element. It'll give a near-instant perception that the room is hotter (if only a little), and (IF efficient, well-placed, etc.) will put most of it's heat down near the floor (where the coldest air lurks looking for bare toes to nip). I use one of those cheap little cube-shaped-heating-elements-in-front-of- a-fan portable electric heaters in the bathroom. It big virtues are that it sucks in cold air off the floor and can be aimed as i please. Ceiling-mounted hot air blowers will be the best at heating air that's too far above your head for your to care and worst at heating cool air near the floor.
24 volt heat for a house? 1000 watts of heat would require 40 amps of current. That would be mighty big wire running to your heater! More likely you have relays (and a separate meter outside the house) so that your utility supplier can shut off your power whenever they want. That also gets you a lower rate. How fast something heats up has to do with how much power you dump into it and the thermal mass that needs to be heated. A radiant floor with low thermal mass and a lot of power input would warm you fast. Being electrical, the temperature that it turns on it could be very close to the temperature that it shuts off at. With solid state switching, it could turn on and off several times a second without any trouble. I personally don't like fans blowing hot air in a bathroom. Even nice warm air moving past you when you are wet feels quite cold due to evaporative cooling. If you want to heat a room up fast for only a short period of time, low thermal mass and a sizeable heater would be my recommendation. I'd steer clear of heaters fill with oil and such since the oil is thermal mass and these heaters are designed for uniform, even heat over a long period of time. I like i's recommendation of using IR heaters. You will feel the IR heat instantly even when wet, no air blowing around to cool you and the thermal mass is almost zero. Electric heaters with long, glowing elements sounds like the ticket for a bathroom. Thermal mass and low wattage heaters for the rooms where you want to maintain a constant temperature. I like radiant floor since it is a more efficient way to heat a dwelling. Heat rises so it makes sense to introduce it as low as possible. Even heating contractors reduce the required BTU input, to heat a dwelling, by 15% if you go with in-floor heating.
Jim says he has done real-live tests in his bathroom and finds that, at least in a cold room (55-60 degrees with colder walls) radiant heat only heats one side of you, but the hot air stream wraps around you. It also dries you faster. Perhaps the situation is different in a room which already has 60 degree or warmer walls. In my bathroom, which is in the basement and has a 50 degree or colder floor and walls, even after I heat it to 60, radiant heat works fine for standing in front of, but blowing air might work better. I should try the experiment here. The problem with floor heat is that, if you include all the thermostats and other wiring needed, it would cost about $5000 to install. Baseboard heaters run about $40 each, plus a $20 thermostat, and we have eight rooms. Also our floors are high-mass (1.5" concrete) and rather than keep constant temps in the whole house the idea was to heat the whole house to some minimum and then turn up heat in the room that you are in. (I cannot be everywhere at once). How much longer does it take for an 'oil-filled' (or other high-mass, such as heavy steel or aluminum) heater to heat up than a lightweight one? I suppose we ought to run experiments on how long it takes to heat up a room 2 degrees with each type. We won't have a lot of temperature swings in any case because the house itself will be high mass and absorb the swings. And lose heat very slowly. We forgot to turn off one experiment yesterday (a 1500 watt heater set on maximum temp) and after about 24 hours the top floor was up to 65 degrees. Ten hours later it had cooled to 62 degrees. 40 out now, 30s at night. The house had been tending towards 45-50 without heat but higher with teh sun shining. Friday the upper porch, with leaky plastic on it, was 90 degrees at 2 pm, and it heated the house to 70 after I opened the doors to it. The heat gained is draining to ground now because we have no insulation beneath the floors. One subzero night last year we forgot to close the door to the porch and the next morning it was about 10 out and 38 in. At 40 degrees north latitude (somewhat south of here) December vertical surfaces gain 1646 btu/ft2. We have 200 ft2. 1000 watts/3400 btu. Under ideal conditions, south of here, the porches could produce 97 KW in 24 hours. 4 KW/hour, same as four 1000 watt space heaters. For 48 degrees it is 1304 not 1646 or 3 space heaters, averaged over the day. I calculated that at zero out you need 2200 watts to maintain 70 degrees, so two sunny days would in theory produce enough heat to keep the house warm for three days, under ideal conditions. This is a reason for a high-mass house. ON cloudy days we will bake bread.
Yes, radiant heaters will only warm the side of you facing the heater. You would want such heaters in all four corners of the bathroom to toast you evenly. IR is, after all, just light. It does not go around corners and other things in the room can shade you from it.
That is one problem with ceiling heat while it is running - hot head, cold feet, especially under a table or desk. The primary advantage of ceiling over or floor heat over other sorts is that they take up no space. They are also quiet, as no metal expands and contracts, but my portable 'oil-filled' is also pretty quiet. The aluminum-finned non-portable types make small clicking noises after they go off, as the fins contract. The various makers advertise their products in glowing terms, making them seem like magic. 'Gentle heat keeps radiating even after the thermostat turns off because of the hydronic element's retention qualities' (Translate this as: it takes a while for the thing to warm up so it keeps heating after you turn it off.) 'Designed for quiet operation. No popping and pinging normally associated with baseboard heaters'. (None of ours pinged, and the pops were miniscule - maybe they are all comparing themselves with models from the fifties?). Carrying Handle on All Models. Lets you carry your heater from room-to-room. On/Off Light on All Models. Lets you know heater is operating. When you turn the heater on the light goes on. Turn the heater off and the light goes off. Wattage Indicator Lights on Model XXXXX... (fill this one in yourself) Automatic Thermostat - Automatic thermostat lets you maintain desired comfort level. Merely dial up or down to the level of comfort you prefer. (Translate - there are no numbers on the thermostat since we did not calibrate it). The thermostat will automatically control the heater to maintain that level. Heater design produces gentle, radiant heater even after the thermostat's been satisfied. (More free heat for the foolish). The above is from a well-known manufacturer. The off-brands are more creative. One little diagram of how ceiling heat is better than baseboard heat shows a 95 degree ceiling and 70 degree air and floor for the ceiling heat, but for baseboard heat 150 degree air above it and a 60 degree floor. Almost makes me want to climb a ladder and measure. Perhaps they took their measurements over an unheated garage with no insulation in the ceiling of it? Humidification is unnecessary with a radiant system......The air isn't dried out by combustion. (Does combustion burn water to air?) Because there's no need for fans or blowers, healthful humidity levels are maintained by radiant heat. (I think they are trying to say that moving warm air dries out your lungs). Radiant Glassheat is ecologically balanced heat like the sun. .... Only radiant heat is truly natural heat.... ....the closest thing science offers to match natur'e own way of heating. .... no drafts, no cold spots or hot spots (how about under the table?). Radiant heat does not dry out the air. No artificial humidification is required. (Perhaps they are saying that there is less infiltration than with an old-fashioned furnace which draws dry outside air in through cracks around the windows?) No fuel is burned, therefore no dust or dirt is generated or carried about to streak walls and soil furniture. (Baseboard heaters supposedly streak walls without burning fuel, they burn dust that lands on them, and furnaces are not supposed to be putting the combustion products into the house - perhaps they are comparing their radiant heat with an open fireplace?) Then there is the Thermaray company, which is predicting that electricity will be much cheaper than gas or oil in the near future, and then lists today's heating costs for a 1200 square foot house. At 10 cents/kwh $988 for baseboard, $741 for their radiant product (turn your thermostat down 6-8 degrees....), $1134 for the highest-cost gas ($13/50/mcf) and $843 for il ($1.70). Electric resistance cheaper than gas? This is one of many companies that says if the walls are warmer the air can be cooler for the same 'comfort level'. So you can turn the thermostat lower. They neglect to point out that it takes more energy to get the walls warmer, so that, even if the thermostat may be set lower (it measures air temperature) the heat may run just as long to get the thermostat to that lower temperature as it did with an air-heating system for a higher air temperature, since the heat goes into the walls, not the air. For warmer walls, add insulation! I have been finding 60 degree air with 9" wall insulation too hot at night. Solar hot air 'makes air, fan or expansion noises.' Our porches do not. Compare ceiling heat with baseboard electric heat: They claim a 15 degree temperature difference floor to ceiling. We managed to obtain only a ten degree difference when heating the upstairs and not the downstairs, and it did not maintain itself for long when the heat went off. Economical 95 degrees for ceiling heat. Inefficient 150 degrees for baseboard heat. (The ceiling cannot be made warmer or it will deterioriate. The higher temperatures actual transfer heat much more efficiently - faster). Ceiling radiates heat long after thermostat is off. (Of course it does not radiate much heat for the first hour or so after the thermostat goes on). Baseboard heaters: low humidity, hot air temperature reduces relative humidity. (Yes it does, for the 150 degree air coming off the heater, but this mixes with the rest of the room air, which ends up the same temperature no matter which system you use, unless you only breathe the air coming right off the heater you will not notice a difference). Gypsum will not rust. (Can't argue that one.) Metal will rust - look at any two year old bathroom heater. (I looked at our 25 year old heater and there was no rust. Bathrooms should not be kept in a state of constant high humidity or the chrome plating will also deterioriate). It works like a magnet: just as iron is attracted to the magnet, cold objects attract heat energy. Both are electro-magnetic forces, operating under similar principles. (Heat is magnetic?) Enerjoy radiant heatmodules (ceiling panels): A single 2x4' Peopleheater is all that is required to provide primary heat for your bathroom..... with 60% less wattage than a space heater. (Are they saying that you need two of these to give as much heat as a space heater, or is it possible that one of these gadgets can convert 610 watts of electricity into 1500 watts of heat?) Companies with the least ridiculous advertising are RaySol (RayChem), which sent us out some very useful information on how to calculate and install heating cable in floors, and Markel (The Choice of Professionals Since 1921, sold by Madison Electric). Exclusive high mass all steel element - heats and cools more slowly reducing room temperature fluctuations, expands and contracts half as much as aluminum reducing the opportunity of disturbing noises. We have a Markel aluminum-fin type heater with floating element suspension to eliminate expansion noises. Designed for clean wall operation - the air comes out the front, not the top, in all the heaters that we have, eliminating scorch marks.
I've been pretty happy with the radiator heating in two of the three apartments I've had that had it. The third apartment had a leak somewhere letting air into the system, such that it would stop working and need to be fixed every few weeks, but that was a maintenance problem. The forced air heat I grew up with in my parents' house seems to work pretty well for heating. I was reminded this weekend just how dry it gets there, and why I tended to prefer radiant heating when I lived in Michigan. I'm still undecided about my current forced air heat. It blows air through very fast. That means it heats very effectively and never has to run very long (it probably helps that it hasnt' gotten really cold here since I moved in), but it also means that the air rushing through the vents sounds extremely noisy. The furnace is also apparrently anchored to the bottom of the dining room floor, which means that the furnace fan can use the floor as a sounding board. Being in my dining room when the furnace comes on sounds somewhat like a jet engine taking off. Again, though, I think that's an implementation issue.
The humidity level has more to do with how air-tight your house is. Yes, combustion of most fuels produces water but the water is not wrung out of the air in the house. It's simply a product of combustion. Most fuels contain hydrocarbons. The hydrogen combines with oxygen to produce the water. The humidity in our house has never been below 52% with the air-to-air heat exchanger running and climbs to 60% with it off. This doesn't really prove anything because or house is heated by the floor and the sun, when it shines...
Houses with furnaces that are not designed to draw in air directly to the furnace, even if they are as air-tight as a house with radiant heat (hot water, steam, electric of any sort) are more likely to be drafty and pull cold low-humidity air in through cracks, which is why the air is drier in them. Fireplaces also provide a lot of ventilation and dry the house house that way. The water produced by burning fuels does not usually go into the house (only in the case of unvented heaters, which are not healthy, and include kitchen gas stoves). It goes up the chimney. Much of the heat is transferred from the air containing the combustion products, to the air that circulates around the house, through a metal plate (or stovepipe). Baseboard heat should feel about the same whether produced by circulating hot water or circulating electrons. I don't like the forced-air type either, but a forced-air (fan-type) electric space heater lets you get a lot more heat into a smaller heater without overheating it, because it blows the heat away into the room. That would be the advantage of using one to quickly heat up a bathroom where there is not 6' of free wall space for a baseboard model, only wall or ceiling space. We will be getting a special interruptible HVAC rate for our electric heat in combination with the water heater, and have to figure out how to install a relay and 24 volt wiring to each heater so that they can shut it off, along with the water heater, during peak (May-September) days of super hot weather. Normally people have two different rates and meters for heat and hot water, but we are not using enough to justify two meters so they allowed a combination. Tomorrow someone is supposed to call to hopefully give us permission to omit the relays on the space heaters, which they are unlikely to be turning off by radio signal in July, and only use them on the water heater and central dehumidifier. The cost of the extra relays would about equal what we would save in ten years of this special rate. The water heater relay (about $40 plus $20 for a 24 volt transformer) might pay for itself in four or five years. The other option is a large gadget called a contactor that disconnects all 10 circuit breakers and is itself the size of a breaker panel and costs about $1000. The relays just interrupt current to the individual heaters. To use low-voltage thermostats you also need relays, or you can use line-voltage thermostats in the heaters themselves, supposedly less accurate but an awful lot easier to install, or electronic line-voltage thermostats on the wall, which require more 220-volt wires to them and a positive disconnect (?terminology). The baseboard heaters themselves are $25 and up, the line-voltage thermostats start at about $20, meaning the relays and transformer would more than double the cost of the heating system.
Forget relays and interruptible rates. We do not have permission any more
to put the heat on the special 5 cent/kwh rate used for Air Conditioning and
Heat Pumps or Water Meters. They suggested the Whole House Rate of 6.9
cents/kwh, but neglected to tell me that the rate was actually 8.71 cents
until (unless) you went over 20 kwh/day. Even with heat and hot water we
would not be using that much electricity. The other suggestion was
time-of-day rate, over 13 cents/kwh summer 10 am to 7 pm, otherwise much
cheaper. Under 3 cents/kwh off peak winter, and only 6.7 cents onn-peak.
We will put the water heater on a timer not to run 10 am to 7 pm, and leave
the heat on at night.
Nonviable options I just investigated included: electric storage
heaters, they put the heat into insulated bricks at night and blow it back
out in the daytime. Cheapest model (850 watts in, 6000 watts out and then
dropping off) is $704 suggested list price. Line-voltage setback thermostat
- $86.40. Nonsetback line-voltage thermostat (which can be installed in the
heater or on the wall) $17.50. FOr 8 thermostats setback is an extra $560,
or more than ten years' cost for heat. Low-voltage setback (programmable)
thermostats can be found used, but they require a $60 relay/transformer for
each heater. Baseboard heaters, 500 watts, are up from $99 to $128 for
hydronic (oil-filled) models, and down from $29 to $27 for plain types, which
we already have a few of.
Rather than turn the heat off at night and on in the morning, we will
leave it on all night (which is supposed to be better for the house anyway)
and maybe also boost it 5 degrees before 10 am (we have lots of those plug-in
type times and portable heaters that could be set to run 7 am to 10 am). We
can install some time-of-day outlets as well, and just be sure not to use them
during summer peak hours. (Orange outlets for time of day?) Jim was talking
about rigging up a timer for one 20 amp circuit, to turn it off summers from
10 am to 7 pm.
Off-peak rates are 2.76 cents winter, 3.71 cents summer, on-peak 6.7
cents winter, 13.35 cents summer (air conditioning times). If we heated only
off-peak, it would cost us about $60/year for heat, electrically. If the heat
were on at random times, the rate averages 4 cents, or $80/year. During peak
hours we will have solar heat (on sunny days) and warmer outdoor temperatures.
I love this country. Use more electricity and it gets cheaper per kwh... Meanwhile, Engler is inviting private power producers into Michigan because we have only a 5% surplus during peak power consumption periods. You're better off heating with the fuel instead of burning the fuel to make electricity to run your heater. That process is about 35% efficient while burning it in a furnace or hot water heater is 80% efficient or more. i.e. fewer greenhouse gases for the same BTU's heating your home / whatever.
I've been puzzling on why anyone that believes in economical and resource-saving construction and infrastructure would choose electrical heat. As Klaus says, it is less than 1/2 as efficient as a fuel and hence costs more than double and produces double the waste gases to "help" heat our planet.
If you are going to use electricity, it may be worthwhile to explore on-site generation. With small enough demand, solar panels can probably meet the need. Storage may be a problem, of course.
Wind turbines may be even better. Why would storage be a problem? The weight of batteries is not a problem in a house, as it is in cars.
We will be generating most of our heat with the sunporches, on sunny days.
Gas is much more expensive than electricity in our case because the gas
company charges $8/month plus tax on that to just read the meter. So if the
gas cost $100 we would pay $180 for it. Also the combustion products would
go into the air in town right next to the house. And it would not be as easy
to install, the equipment itself would require a lot more energy to produce
and need maintenance. It would be harder to zone. Natural gas is a more
scarce resource than the coal used to generate electricity, plus we are hoping
more electricity will be generated via solar by the power company. Save the
gas for motor vehicles. $500 or so will install a baseboard heating system
(less if we can use our used heaters, which are free and do not take any
energy to produce). What did the floor heating system cost in materials,
Klaus. (Not even counting time, maintenance, the need to replace movingp arts
eventually).
We may do the whole house on time-of-day if Jim can figure out how to
wire both panels on one meter (if that is possible) and do our canning and
freezing on weekends or late evenings. Only 45 hours/week is peak and we will
not be air conditioning.
Madison Electric sells the storage heaters for half suggested list
price, about $350 not $700. We are better off just heating the house up 5
degrees warmer than normal between 7 and 10 am on days when we don't expect
it to be sunny. The heavy floor and walls will store the heat and release
it for the next 9 hours and I don't mind a large swing (55-75).
Coal is an extremely dirty technology, less efficient than gas, spews quantities of toxic sulfur compunds and mercury and vanadium into the atmosphere, and produces ash that leaches toxics into groundwater. You are being rained on now by the effluvium from coal generating plants to our west. Gas is cleaner and more efficient, and may not be "scarce" if the gas hydrate development works out in an environmentally friendly manner. But I agree that your lifestyle may save more resources than those wasted by the inefficiency of using electricity, with a net social benefit.
A typical American household is apparently expected to use 20 KWh/day of electricity for things other than heat and hot water, as that is the amount you pay for at full price before they give you the electric heat rate. We can heat for a year with what a typical household uses in three months of electricity usage. A typical American car travels 10,000 miles a year. At 20 mpg this is 500 gallons of fuel, which is way more than the energy which would be used to heat our house, and I suspect 500 gallons of gasoline as burned by a car produces a lot more pollution than it would take to make the same thermal value of coal into heat for our house. This is why I suggest that people heat with electricity and save the natural gas for mobile use. What is a gas hydrate development? I could heat my little room up from 45 to 60 in about an hour with 750 watts. Two walls and a ceiling are insulated, the others are leaky drywall next to a 45 degree space. It should be no problem to heat the house up from 55 to 65 between 7 and 10 am. The only problem I foresee is that it will be hard to keep the bedroom cooler than the rest of the house, and it will not even cool off much at night with the heat turned off everywhere. 60 is too warm to sleep in, with warm walls. At 11 am the sunporch and the house were both 45, with very pale sun. Outside was 28. It does not take much sun to be usable for heating. In theory you could heat the sunporch to 35 and still get heat out of it with a heat pump, but again, the energy required to make the equipment and maintain it is probably more than the energy that could be obtained with it. How much sulfur etc. actually get through the scrubbing process of a modern coal-burning plant? I thought most of it was captured and converted to gypsum, useful in drywall, except in the older plants that do not have good scrubbing systems. In the case of cars, the pollution goes right into the city air, as they cannot carry around heavy scrubbing equipment.
Our in-floor system was quite expensive. The tubing alone was around $1 / foot. New technologies are expensive not because the materials are expensive but because the quantities are low and the 'local' knowledge base is low. Any hick can install a furnace, while one would have a much harder time finding someone who can install a radiant floor system. Converting it to run off electricity, solar energy, coal, wood, natural gas, etc. would not be difficult. There is also little to go wrong with plastic buried in concrete. Heating elements fail, so if you go that route be sure they are easy to replace and that there will be a source for parts when they do fail.
We have not found any 'central' type heating system that puts oout 2200 W/hour. How much does your hydronic system produce? In-floor electric heating would have cost about $5000 for materials, and a lot of time laying it out, but no maintenance after that. It would work as off-peak heating since the floor stores a lot of heat. Madison Electric told me that their oil-filled heaters are five times the cost of the plain heaters probably because fewer are sold, not because they cost more in materials. As a rough guess, Klaus's system probably puts out at least four times as much heat as we would need, because his house has twice the heated space and about half the insulation. 2200 x 4 x 3.4 BTU/Watt hour = 30,000 BTU to maintain a steady temperature, and more than this to be able to heat the place up quicker. Am I close? What size does the smallest furnace come in? How much would the house cool off at night with the heat off?
"W/hour" is meaningless. Watts are power, or energy-per-unit-time (joules/sec). I think you mean "2200 W". A BTU is *energy*, not power (a "British Thermal Unit"). There are 1054 joules/BTU, so 1054 watts = 1 BTU/sec, or 1 watt = 3.414... BTU/hour.
Our house needs more heat because we have a LOT of glass. Most of it on the south side. Our ceiling is R-40 or more and the walls are R-20 static and and average of R-35 dynamic. (They are a pi section thermal filter: Thermal resistance-thermal mass-thermal resistance.) An oil filled heater will cost more than a plain heater. Oil filled heaters have to have oil-tight seals for the electrical connections to the submersed heating elements and the oil tank has to remain sealed despite thermal cycling. Plain heaters are just coils of nichrome wire suspended in air. The problem with plain heaters is that the if the coils shift you can get a hot spot that will burn out faster due to the greater thermal stress. The thermal resistance of air being a lot higher than that of oil also means that more resistance wire has to be used to to minimize this stress. Oil, on the other hand, has much lower thermal resistance than air. It is also a fluid that conforms to the container that holds it. The heating element in oil heaters can dump lots more watts per inch, without getting too hot, because the oil carries the heat away faster and it can distribute it to to the much larger surface area of the container. The oil can be thought of as a thermal impedance matching device between the heating element and the air.
We are thinking of using our portable oil-filled heaters (four of them) if the city will allow us to wire in just 3000 watts of heater (in the bathroom and laundry room). The one I am using gurgles softly once in a while and has a faint click when the thermostat goes off but is otherwise silent. Plug-in lets us run them through a timer rather than buying a $70 setback thermostat which consists of a thermostat and the same sort of timer, together. Does anyone know how to wire two breaker panels to the same meter. Jim thinks he should run two wires from the meter to the two panels (after pulling the meter so as not to electrocute himself, and getting Edison's permission to do this). The oil filled heaters are 2" shorter than the plain ones, same wattage. Both have identical looking aluminum fins. We separated our large areas of south-facing glass from the house, as a sun porch, so as to eliminate the problem of heat loss from the house when the sun was not shining. Klaus, did you need to add heat today? At 11 am my leaky sunporch was already 65, with half-sun. Are there sunny days when you still have to run the floor heat?
When the sun shines, no extra heat is needed. I got up to 70 in here both Sat and Sun from just solar heating. I don't think either Edison or the electrical inspector will allow you to wire your utility controlled meter to lighting circuits. You can use that only for heating or hot water. If you do do it, one usually goes out of a breaker in the supplied panel to the sub panel. In the sub panel you get the power to the power buss by back-feeding another breaker. If the panels are right next to each other, you might be able to get away with not having the back-feed breaker. The code requires there be a local disconnect at the panel (So it can be worked on with no power applied to it and so that the person working on the panel is within easy sight of the disconnect. The though being that you don't want a second person turning the power on while you're working on it.) Oh, no, I have yet to see the floor system run when the sun is out.
We still don't know what rate we will be getting. I finally downloaded the 300K plus pdf file on rates from Detroit Edison to compare with the little piece of paper they mail out every year. Converted it to an ASCII file and imported it into WP to shorten the lines, then deleted all the stuff about street lights and schools and electric melting of metals, and got it down to four pages single space that I printed out. The whole house time-of-day rate that they suggested is only for people who use 750 KW/month and want to pay $19/month service charge. That's not us! There is a supplemental space heating rate D1.5 which is $2/month service fee (but you can shut off that meter in the summer, and probably pay $5 to turn it back on). 6.85 cents/KWh. Must have at least 3000 watts wired in electric heat and it can be used in addition to other heat. I suppose our sunporch counts as other heat. For people using only electric heat, they offer in addition to the very expensive time-of-day rate (the $19/month is more than we would be paying for electric heat at the regular rate) a D2 Residential Space Heating Rate. No service fee, and all it gets you is that instead of paying 10.12 cents for amounts used over 17 kWh/day (8.71 cents for amounts under this), you instead get a slight reduction to 6.9 cents for amounts over 20 kWh. I used 99 kWh this past month, which is 3.3 kWh/day, so that we would be paying full cost for the heat unless we use over 500 kWh/month for heat and hot water, which is rather unlikely. The most promising is D1.7, an experimental time-of-day separately metered rate to be used for heat and/or hot water and/or electric vehicle, but contrary to what people at Edison told me, it cannot be used for the whole house (without that $19/month and higher per watt rates). Limited to 3000 customers. They will check and call us back. One meter for most things, and one for heat and hot water (attic fan might count as space conditioning? and the central ventilation and dehumidification system probably will). They said to wire the panel specially for time-of-day but did not say houw, and the person who told us this also gave me incomplete info on rates. THe handout said 3000 and the printout 5000 customers, so maybe they raised the number since the printout came out last January. For a fee of 12 cents/day, you can sell power to the company at 3 cents/kWh. If the heaters have to be hard-wired, there goes our idea of plugging them in through timers. I will just make sure to get up before 10 am and turn on the heat for a bit. Jim has gone back to trying to draw houseplans, but the vector-based drawing program will not let him shorten windows easily. Does anyone have experience with CAD programs that will let you delete a chunk of a drawing and move the remaining parts together? Or shorten the middle vertically?
I used Cadkey. The learning curve on most CAD packages is pretty horrific. Doing work fast with them is a matter of lots and lots of practice.
I still think you should look into generating your own electricity. DetEd is just too confused (and confusing).
I agree. Have a thermostat light off a little 4 to 5 KW generator and use the waste heat to heat your domicile while you sell electricity back to the utility. Better than using the waste heat to boil off treated sewage. That way you can also proclaim yourself an IMBY instead of having people call you a NIMBY (Not In My Back Yard ;-)
If I were using the waste heat to heat the house, what would I then possibly need 4 KW for? I average less than 4 KWh/day electric usage. What do you suggest that I burn to generate electricity for less than 3 cents per kW hour if I were to try to sell the electricity? The generation costs would have to include purchase and maintenance of equipment (which reflect the energy needed to produce the equipment). If I were running a 4KW generator and a quarter of this were waste heat, is the 4KW input or output? Please calculate the costs of generating electricity, taking into account the cost of gas plus $9/month to read the meter, the cost of the gas (how much is needed per KWh?), the cost of the generator (including maintenance), and of course something for the time it would take to install and run this system. Don't forget the costs of installing some system for distributing this waste heat. We have KeyCAD and would only have been using about 5% of the available features, if we could find them in the crowd. Jim has learned that the Erase feature causes all sorts of odd problems of lines reappearing or disappearing, so instead will be deleting entire lines instead of erasing parts of them, and designing the drawing so that this is easy to do. A closer read of the instructions shows that erase is supposed to be used for removing the tails of things that you drew too long, right before printing. Jim is viewing this like whiteout- don't do anything to the page afterwards or it will smear.
You sell the entire output to DetEd. Personally, though, I'd look into solar or wind generation, rather than burning any fuel to generate heat/electricity.
I also agree with the preference of wind / solar power and am looking into doing that myself. I only bring up the generator issue because many people don't have enough solar or wind access to heat their homes with. Generating electricity as a byproduct of heating your home makes the process more efficient than generating heat as a byproduct of generating electricity. This is because it puts the point of both electricity consumption and low-level heat consumption closer to where they will be used, thus reducing or eliminating the losses associated with distribution. Generally, low level heat is not worth distributing and simply dumped in the environment. Heat is the lowest form of energy so why use a higher form of potential energy, in this case fuel, to simply generate the lowest form of energy? Use an engine that burns the fuel with low pollution output, even if it means that it is inefficient. After all, most of the waste heat from the engine can be extracted to to accomplish your primary feat: Heat your home / water. Of course, using energy efficiently is the other side of the same coin.
May we put you in touch with our friend who is experimenting with a windmill
and installs solar power? I agree that it would make sense to generate the
electricity in a place where the waste heat can be used. In some cities of
the world this is already done (steam heat to apartment buildings). But at
3 cents/kWh I doubt that this would cover even the cost of the natural gas
that would be needed for running the generator. It is way more efficient
to capture the solar gain as heat directly, than as electricity, and there
are too many trees around the house for wind power (and probably some
restrictions on how high a tower you can build in the city).
Today the leaky front porch was 30 and the outdoors 20, without sun,
at 11 am. Not quite warm enough to melt the ice for water for the toilet.
Not me; I don't have the extra resources to devote to switching energy sources right now. Where do you get the "3 cents/kWh" figure? Is that what DetEd charges, or what it pays? (I don't know; I've not asked them, since I'm not ready to get into co-generation.) Yes, solar heating is more efficient than solar electrical generation. But it is not "either/or"; it's "and/both". You can do it both ways, y'know.
As it is, not many people get any kind of payment for heating their home. I met your friend who installs solar panels and experiments with wind turbines. I don't see any need to met with him as I'm pretty well informed on the subjects as it is. My more immediate goal is to install a little 400W generator on a surplus tower to evaluate the wind potential of my site. (It's just about as expensive to instrument a site for evaluation. I'll use the wind genny as my instrument and sell it if it doesn't work out.)
As I recall, from a friend who had a 10KW Jacobs generator on a 95' tower, DetEd pays .07 cents / KWH and charges $20 a month to read the buy-back meter. This was about 5 years ago, just before he sold the thing. (It came with the house he bought and needed regular service, not to mention a new set of blades. He is not the tower climbing mechanical type.)
I downloaded the latest rates from the detroit edison site, and they said 3
cents/kwh was what they paid, and 12 cents/day charge. This might still be
cheaper than maintaining a battery system, at least if you are on their time
of day rate and can buy back the power at about 3 cents off peak. Seems like
they might offer to pay you more during on-peak times since they charge more
then. They may have changed their attitudes towards solar electricity now
that they are generating their own. Were you planning to actually run
anything off your wind generator?
I think A2 building code has some rule about structures being only up
to about 35' high. I wonder if they count trees in this rule, or if you could
affix a generator to the top of the black walnut. Would your tower attract
lightning?
DE has not called me back for two days about rates, or if they did,
I was online posting the information on grex :=).
After reading in Dream of the Red Chamber about how the aristocratic Chinese
used to use footwarmers, I am testing out something called an Air Dryer that
Jim rescued from Kiwanis recycling. You just plug it in, and it emits 130W
of heat through the little holes in the top of an aluminum box. It also says
CAUTION Hot Surface Avoid Contact. It is keeping me much warmer, with my feet
occasionally resting on it while it sits under my desk, than was a 1500 watt
quartz heater. But I am at 60 degrees already, and this gadget was not
perceptibly useful at 40 degrees at the building site.
Another highly efficient source of heat, as Rane already knows, is
internal hot water. For warming hands, there is my 40 watt desk lamp. This
is really cozy! Under the lamp and next to a computer it is 65. I will heat
my house with computers.
The Air Dryer should also be handy for rising bread on, or making
yogurt, or even drying wet gloves or boots.
Despite evidence to the contrary in the pdf list of rates, rate D1.7, for space conditioning and water heating, is no longer experimental, nor is it limited to 5,000 customers. The limit is now 10,000 and they have apparently not been flooded with applicants as there are only 2500 accounts so far. No special way of wiring it. Our central 'heat pump', 'air conditioner' and 'heat moving system' qualifies (if we make sure not to use the word dehumidifier). It will be a 2000 watt air conditioner if we redirect the heat generated by dehumidification outside in hot weather, and will be a heater if we keep the heat but drain off the water when it condenses. So if we run this continuously, it might be accepted as enough heat for the house (assuming we can feed it enough vapor). WOuld it qualify as a geothermal heater, if we can get enough ground water to evaporate into the house air? We can recover any heat put into hot water if we let it sit in the tub or sink until reaching room temperature.
Today I did a test of temperature stratification at the building site, in a little room with insulated ceiling and outside walls, and leaky uninsulated interior walls and floor adjacent to a 40 degree area. The temperatures, while the heater was running, were 64 just above the heater, 64 at the ceiling, 62 a foot off the floor on furniture, but on the floor itself (on a rug) 54. If the floor were insulated or above a heated space, I would expect only a 2 degree spread. Heated floors probably are more of an advantage when the floor itself would otherwise be cold (not insulated, over a cold area or slab). Klaus, have you considered geothermal heat from your well to heat your floor-heating water? We know of two local systems using ponds.
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- Backtalk version 1.3.30 - Copyright 1996-2006, Jan Wolter and Steve Weiss