[RonArt]

My intent is to help heat the house in winter. Could the output of a turbine heat a new heater element in an existing house heater? (The heater's fan takes off by itself while heat is registered). Here's the math.

Let's say you've got eight 100-watt bulbs running all day, every day. That's 800 watts per hour, .8 KWh, not quite 1,000 watts per hour.

Let's say a KWh costs 20 cents. Then, .8 KWh(s) cost 16 cents, $.16.

Let's say a $100 wind turbine can deliver that .8 KWh(s) uninterrupted. Then, it would take 625 hours to pay for itself. That's 26 days.

Hmmm, how do HOA feel about these? Also, are there any tax breaks available? Is noise an issue?

 

[user_12345a]

Wind turbines don't provide uninterrupted power and cost far more than you think and no one in the right mind would hook one up directly to heat water.

Honestly it seems like you're trying to get answers to simple homework questions or something because this doesn't reflect a real world scenario.

 

[beenthere]

Or, you could go out and buy a portable electric space heater for say 50 bucks. Run it on low, at say 750 watts. And in 333.33 hours/13.88 days. It will have used as much electric as it cost to buy the heater. The same as you using 8-100 watt light bulbs and operating them for 26 days, to use the same amount of electric as you paid for a turbine.

 

[RonArt]

I've got a Utilitech 1500-watt radiator style electric heater. It has 2 knobs: one has 3 (wattage?) settings and the other is a variable (temperature) potentiometer. While the oil can be heard sloshing when the unit is tilted, it is electric. BUT it is also Alternating Current. Heating with electricity is not as efficient as heating with gas, but much easier to relocate and it doesn't explode. I'm hoping to find something that can be inserted in a home furnace, to take advantage of the distribution. The power going to it would not have to be constant.

One concern I have always had about heating with electricity is the conduction of the heat it generates traveling down the wire that feeds it. Anybody know how that is kept in check?

 

[Oso954]

A lot of HOAs are going to prohibit wind turbines. Many cities have zoning laws that also prohibit them either in city limits, or in specific zones such as residential. So, you need to ask both your HOA and your AHJ.

Wind turbines are noisy, particularly the small ones that turn at higher rpms than the larger ones. The worst thing is a roof mounted turbine (or tower on roof). It can turn your house into a sound box and the noise/vibration can drive you crazy.

Have you investigated what your average annual wind speed is ? It takes a lot of wind to make small turbines pay off. You need to do your pay back calcs based upon how many hours of wind you have at what wind speed.

An 800W Turbine will probably Produce 800w only at wind speeds above 25mph (28mph is common). It won’t even start turning Until you have something about 8mph. The generation of a few watts might start about 12mph.

Dont guess at the wind speeds. You need to look them up or measure them. Most people are very bad at guessing wind speeds.

 

[lenaitch]

I've got a Utilitech 1500-watt radiator style electric heater. It has 2 knobs: one has 3 (wattage?) settings and the other is a variable (temperature) potentiometer. While the oil can be heard sloshing when the unit is tilted, it is electric. BUT it is also Alternating Current. Heating with electricity is not as efficient as heating with gas, but much easier to relocate and it doesn't explode. I'm hoping to find something that can be inserted in a home furnace, to take advantage of the distribution. The power going to it would not have to be constant.

One concern I have always had about heating with electricity is the conduction of the heat it generates traveling down the wire that feeds it. Anybody know how that is kept in check?

Oil-filled electric heaters are fairly common.

Heating with electricity is more efficient than any fossil fuel. Electric is 100% efficient since all input energy goes to heat - somewhere. I'm not aware of a 100% fossil fuel combustion device. Energy loss in conductors cannot be avoided but can be managed. If the cord conductors on your heater are getting inordinately warm, they may be undersized.

Does your home furnace not already have a fan?

I did a quick Internet search and noticed that small, house-sized wind generators max out about 400-500 watts, nowhere near what you would need. They are also direct current, which means that, even if it was a viable idea, you would need an inverter and without storage (batteries), you would have a fan only when the wind blows. Alternating current wind turbine are much more complex since they need to turn at a specific speed and the energy cannot be stored.

 

[Old Thomas]

Just run the 8-100 watt bulbs, most of the power goes to heat anyway. Over 90% of the power goes directly to heat and the rest that goes to light turns to heat unless it goes out a window. Virtually the same heat as an 800 Watt heater with free light.
If you can buy 100 Watt incandescent bulbs.

 

[viper]

Resistive heating with wind cannot be done practically. All energy sent to the heater is used 100% efficiently, but you need a LOT of power! Have no idea of home location or size but 800w is 2730btu/hr. Consider that that a home might need 50k btu/hr heater running at 50% duty cycle, so lets say 25k btu/hr. You would be a factor of TEN off from where you need to be. Now you need an 8kw genny!

I did not get precise in my calcs, just proving a simple point, you cannot recover your investment by dumping wind power into resistive heater. A resistor CAN eat AC or DC power as long as you do it right, but that won't matter here.

The best way to utilize electric for heating is a heat pump! This relies on the same principle as an air conditioner. It pumps heat from outside, inside your structure. It can be hard to grasp how you can extract warm air from 30*F outdoor air, but it works, and uses much less electric power to do it! This performance comparison is referred to as the COP or coefficient of performance. As a basic example, if you have a COP of 4, that means the unit would be moving 4x the amount of heat as it uses in electric. So 1000W in = 4000W(13650btu/hr) of heating performance indoors.

Again, I did not go into detail here so hopefully the pros don't beat me down.

 

[HotRodx10]

Oil-filled electric heaters are fairly common.

Heating with electricity is more efficient than any fossil fuel. Electric is 100% efficient since all input energy goes to heat - somewhere. I'm not aware of a 100% fossil fuel combustion device. Energy loss in conductors cannot be avoided but can be managed. If the cord conductors on your heater are getting inordinately warm, they may be undersized.

Does your home furnace not already have a fan?

I did a quick Internet search and noticed that small, house-sized wind generators max out about 400-500 watts, nowhere near what you would need. They are also direct current, which means that, even if it was a viable idea, you would need an inverter and without storage (batteries), you would have a fan only when the wind blows. Alternating current wind turbine are much more complex since they need to turn at a specific speed and the energy cannot be stored.

Electric heating is not 100% efficient. It may be close, but there are always losses along the way before it gets to the heater. Heating with fossil fuels well below 100% efficiency; however, it still costs far less per BTU (or KwH) to heat with natural gas or propane (or burning wood, wood pellets, corn, etc., though the stove may be expensive). I calculated the cost per BTU of heat with my local utility prices to be about 6 times higher for electricity.

I also live in one of the best areas of the country for wind energy, and the payback period for a wind turbine (If I design and build foundation myself) is between 10 and 15 years. That's just for the electricity I use for things other than my main home heating, water heating , and stove, which are all natural gas. If I switched over to heating with electricity, the payback period would be well beyond the lifespan of the turbine.

The most common way to set up a wind turbine is to tie it into the electric 'grid', so that you get credit for all the electricity your turbine uses, but you also power available anytime you need it.

Passive solar is the far more efficient and simple way to heat water.

 

[Old Thomas]

Actually 100% of the energy used in lights is distributed as heat. This is why all light loads are calculated as heat gain for cooling calculations. All light eventually turns into heat.

Sounds familiar. Oh, yea, that is what I said.

 

[viper]

Sounds familiar. Oh, yea, that is what I said.

There ya go, I fixed my post as I misread. Don't need any online pouting.....lol

 

[Old Thomas]

No pouting, no whining, no sniveling.

 

[CaptTom]

Electric heating is not 100% efficient. It may be close, but there are always losses along the way before it gets to the heater. Heating with fossil fuels well below 100% efficiency; however, it still costs far less per BTU (or KwH) to heat with natural gas or propane (or burning wood, wood pellets, corn, etc., though the stove may be expensive). I calculated the cost per BTU of heat with my local utility prices to be about 6 times higher for electricity.

Exactly. This is often misunderstood, and bears repeating.

"Efficiency" can be measured many different ways. As a homeowner, if you are comparing costs, you need to look at them in relation to some common factor, like BTU's.

In theory, every bit of the electricity brought into your house is turned into heat somewhere. Sure, the power plant has a specific efficiency rating, and there are losses in transmission. But you're only paying for what comes through your meter. For a heating appliance of any kind, be it a bare resistance element or a fancy looking radiator filled with snake oil, all the energy you paid for is turned to heat.

A gas furnace or oil boiler is rated at less than 100% "efficiency." Each unit of oil or gas you buy has some BTU value, but a lot of that goes up the chimney. So when comparing your heating costs, you have to factor that in. And in most places, electricity will cost you more per usable unit of heat than other options. Usually a lot more.

Now, if you're comparing environmental costs, then you have to factor in the "efficiency" of the power generating plants which are supplying you. And then the extraction impacts of those fuels, and the impact of the plants themselves, and the infrastructure, and transportation impacts, and the waste products of the extraction, and so on.

 

[lenaitch]

Electric heating is not 100% efficient. It may be close, but there are always losses along the way before it gets to the heater. Heating with fossil fuels well below 100% efficiency; however, it still costs far less per BTU (or KwH) to heat with natural gas or propane (or burning wood, wood pellets, corn, etc., though the stove may be expensive). I calculated the cost per BTU of heat with my local utility prices to be about 6 times higher for electricity.

I also live in one of the best areas of the country for wind energy, and the payback period for a wind turbine (If I design and build foundation myself) is between 10 and 15 years. That's just for the electricity I use for things other than my main home heating, water heating , and stove, which are all natural gas. If I switched over to heating with electricity, the payback period would be well beyond the lifespan of the turbine.

The most common way to set up a wind turbine is to tie it into the electric 'grid', so that you get credit for all the electricity your turbine uses, but you also power available anytime you need it.

Passive solar is the far more efficient and simple way to heat water.

I suppose you are correct in the sense of a distributed grid, where there are efficiency losses at the source of generation, heat losses in transmission, etc., but from the point of view of the consumer, at the meter or the wires exiting a wind turbine, the losses between there and the load would be negligible.

There is a difference between energy efficiency and cost efficiency.

 

[HotRodx10]

I suppose you are correct in the sense of a distributed grid, where there are efficiency losses at the source of generation, heat losses in transmission, etc., but from the point of view of the consumer, at the meter or the wires exiting a wind turbine, the losses between there and the load would be negligible.

Assuming the power line is not long and is of sufficient size, you're correct - losses are negligible, but they're never zero.

There is a difference between energy efficiency and cost efficiency.

Definitely, and the cost efficiency skews heavily towards combustible fuels or direct solar heating. CaptTom summarized both types of efficiency very well.

 

[viper]

I realize you guys replying all grasp the same concepts, but I just cringe when I hear "efficiency can be measured different ways".... Let me say this right from high school physics 101, energy efficiency = energy out/energy in and nothing more. Where the confusion comes is the "cost for that energy" because it is sold in different ways and people not in these fields don't know!

1W/hr = 3.412 btu/hr thus 1000W/hr = 3412btu/hr
1 kw/hr = 1000W/hr

In our area 1 KWH of electric costs about $.14
In our area a therm of Natty gas costs about $1.00 A therm is right at 100,000btu

So if you move the numbers around
A KWH of electric is 3412btu/hr but a therm is 100k btu/hr

So if we get this straighented out, it will ta 29.3 times more KWH to get you 100,000btu/hr so ......

Price per 100,000btu
Natty gas - $1.00 per 100,000btu
Electric - $4.10 per 100,000btu

By that simple comparison, electric costs a whopping 4x more! So all things being equal, even if electric resistive heating is nearly 100% "efficient", it would take a gas conversion efficiency of only 25% to compare to that!

Put this another way, if both gas and electric were 100% energy efficient for making heat in your home, gas would cost 1/4 as much!!!!

 

[beenthere]

Efficiency can be measured, rather easily. However, people tend to confuse high efficiency from one energy source to another with lower cost. When the only thing that makes one cheaper than the other, is the cost of that fuel on a like for like energy comparison.

 

[HotRodx10]

I realize you guys replying all grasp the same concepts, but I just cringe when I hear "efficiency can be measured different ways".... Let me say this right from high school physics 101, energy efficiency = energy out/energy in and nothing more. Where the confusion comes is the "cost for that energy" because it is sold in different ways and people not in these fields don't know!

1W/hr = 3.412 btu/hr thus 1000W/hr = 3412btu/hr
1 kw/hr = 1000W/hr

In our area 1 KWH of electric costs about $.14
In our area a therm of Natty gas costs about $1.00 A therm is right at 100,000btu

So if you move the numbers around
A KWH of electric is 3412btu/hr but a therm is 100k btu/hr

So if we get this straighented out, it will ta 29.3 times more KWH to get you 100,000btu/hr so ......

Price per 100,000btu
Natty gas - $1.00 per 100,000btu
Electric - $4.10 per 100,000btu

By that simple comparison, electric costs a whopping 4x more! So all things being equal, even if electric resistive heating is nearly 100% "efficient", it would take a gas conversion efficiency of only 25% to compare to that!

Put this another way, if both gas and electric were 100% energy efficient for making heat in your home, gas would cost 1/4 as much!!!!

As I wrote earlier, I calculated the cost for my area at about 6:1. You may want to take another look at your utility bill to make sure you included all the costs based on demand and removed the fixed costs, such as facility charges, from the calculation. Not saying you're wrong; maybe gas is that much more expensive in your area.

Regarding the specific case of the OP (heating water), a table I found here indicates that water heating with electricity is highly efficient (90-95%), heating with gas is fairly efficient (65-80% - surprisingly, that difference is all in whether it has a pilot light), and a heat pump water heater is 220% efficient, which means you get 2.2 times as much heat energy delivered as the electrical energy it takes to run the heat pump. Solar with electric backup is reported as 120%, which would presumably vary widely depending on when hot water was used, i.e. how much was heated by the sun and pumped with electricity vs. direct electrical resistance heating. The efficiency of the portion where all the heating in done by the sun and the only electricity required is to circulate it, probably approaches or surpasses that of the heat pump system.

Based on that table, the energy efficiency difference between gas and electric resistance heating of water is generally between 20% and 40%. If electric heat is 600% or even 400% more expensive, the cost to heat water with electricity is still far higher. At best, heating water with electricity from the grid is still 333% more expensive than with gas. So if the payback period for a wind turbine is 15 years replacing grid electricity (typical in a moderately good wind potential area), it's at least 50 years vs. heating water with gas from the utility. Of course there are other cost considerations if you don't have the supply lines and venting for a gas-fired WH, which can be a significant initial cost.