# Simple solution? Oil fired FHW



## babalu87 (Nov 8, 2007)

The only time my oil burner runs if for hot water. The house is heated 100% with the wood stove.
It is a tankless system with an expansion tank and we have baseboard heat.

Would it be more economical to have storage for the hot water? The boiler runs during the day just to maintain hot water and then runs again for showers etc.
I am planning building something solar this winter or at least getting it laid out and finish gathering materials but there has to be a fairly simple solution to at least assist the boiler in heating the hot water. As simple as a well insulated 55 gallon plastic barrel?


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## Eric Johnson (Nov 8, 2007)

Offhand, I'd say you'd be ahead to shut off the boiler and get an electric hot water heater, or buy an oil-fired hot water heater. I don't think using a boiler exclusively to heat DHW is a good way to save money.

But I'm just guessing. This would be a good one for castiron, who seems to have his act together where things electrical are concerned.

Also, babs, you might try posting your question over at heatinghelp.com. They have a bulletin board called The Wall where HVAC pros answer homeowner questions. I'd be interested in their replies; you might get some diversity of opinion, but all of it will be well informed. They know a lot about solar as well.


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## babalu87 (Nov 8, 2007)

Thanks Eric for that site, I posted and will copy/paste replies here.

When we built the house oil was .85 a gallon and propane was cheap too.
I really should have addressed the hot water when I installed the wood stove.
Tankless hot water is pretty economical when heating a house with the same system but it is like pissing into the wind now. Than damn thing runs all the time because the basement is so cold.

We have a propane dryer and oven, propane is at $2.90 a gallon on the latest bill.
By comparison electric is under 9 cents per KW
I think the way to go for us is with an electric hot water heater, I just need to figure out if it should be a tanked system or tankless.


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## titan (Nov 8, 2007)

For my money I'd install a 40 gal. electric tank.The new 'smart' tanks use a rigid foam for insulation, cuts down on standby heat loss better than the old fiberglass insul. tanks.If the tank goes in the basement get it up off the concrete floor with 2" Sm styro. underneath.


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## babalu87 (Nov 8, 2007)

Titan, that is the route I think we will go.
I was thinking of building some type of shelter for it as well to help insulate it from the cold of the basement.

Hell, with tax credits etc I can get a HW heater for about the cost of filling my oil tank.

I'd like to know approximately how much juice a 40 gallon electric heater uses for 4 people one dishwasher and all laundry done with cold water.
There must be somewhere to figure out how often it will be"running'


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## Nofossil (Nov 8, 2007)

I had the exact same situation, but my boiler needed a heat storage tank for efficient operation. I left my indirect oil-fired hot water heater in place, but my domestic water is heated in several different ways:

1) The cold well water runs through a coil in the heat storage tank before going into the bottom of the DHW tank.
2) The storage tank is heated by solar in the summer and wood in the winter.
3) If the storage tank is hot enough and the DHW tank needs heat, I circulate water from the storage tank in place of water from the oil boiler
4) If the wood boiler is operating, it heats (actually, superheats) the DHW tank.
5) If the oil boiler runs for any reason. once the demand is gone any extra heat in the oil boiler goes into the DHW tank.
6) Finally, if all else fails, the oil boiler heats the DHW just as it did originally - just nowhere near as often.

I kept the oil because it's also a backup to heat the house when we're away.

Here's a link to a writeup on my hot water system - I think you've already found my writeup on my hot water solar panels.


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## n1st (Nov 9, 2007)

Funny, I was going to post this exact question.  I'm in the same boat but my electricity is $.21/kwh, so I guess I'm in a worse boat.  

Just started researching tonight.  Have you looked at the on-demand propane/gas/oil water heaters?  They do look interesting.  Anyone have one of these and can comment on them?


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## Nofossil (Nov 9, 2007)

N1ST said:
			
		

> Funny, I was going to post this exact question.  I'm in the same boat but my electricity is $.21/kwh, so I guess I'm in a worse boat.
> 
> Just started researching tonight.  Have you looked at the on-demand propane/gas/oil water heaters?  They do look interesting.  Anyone have one of these and can comment on them?



My brother has a propane model and loves it. It does have some limitations if you want to combine it with other energy-saving concepts such as preheating your hot water with wood or solar. The on-demand units supply a fixed amount of heat. If you try to use preheated water, you run into overtemperature/underflow problems. Topic for another post....


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## cbrodsky (Nov 9, 2007)

I would suggest an electric tank is worth thinking about depending on your local electric rates.

You will hear a lot of fairytale stories about how tankless heaters will save you a fortune.  It is smoke and mirrors IMHO compared to a well insulated tank sized right for your house - you'll never recoup the capital cost, and they're bad for the grid.  And electric rates are getting close to heating oil these days.

1 kWh of power = 3412 BTUs.
1 gallon of oil = 139,000 BTUs.

With electric, all the energy goes right into the water tank.  Your oil burner at best is probably doing about 75% efficiency for transferring heat, so out of that gallon, you probably only get 104,250 BTUs.  This is equal to 30.6 kWh.  If you're paying about $3/gallon for oil, and $0.10/kWh for electric, then the two costs look pretty similar.

Next, you have to consider standby losses - an oil boiler will lose a lot more heat while it sits idle as compared to a well insulated electric tank.  I have not seen as much good data on this, but some studies claim overall boiler efficiency for tankless coils can drop to 50%.  This further tips the scale to make electric look better.

You can run the math on your power rates to see how it works for you to help decide how close the options are - a couple years ago it would be crazy to consider, but now it's not such a bad idea.

In my case, I am using solar to partially heat the water this time of year and using electric to finish it off.  This is letting me keep my boiler off much later than normal.  But once I fire up the boiler, I'll turn off the electric and use oil to finish heating the water.  I paid $2.39 this year for my tank of oil and electric is about 0.12 so easy decision IF I have to have the boiler on for heat use anyway - at that point, I'm already paying the standby loss penalty for home heating needs. 

-Colin


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## cbrodsky (Nov 9, 2007)

ps - a local outfit was offering tankless gas/oil water heaters installed for about $3,000.  For that price or incrementally more, you could probably swing a solar installation in NY State after tax credits - much much smarter investment than something that will still require expensive fossil fuel to run.  And in the case of oil, far more maintenance than a drainback solar HW system requires.

-Colin


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## babalu87 (Nov 9, 2007)

Nofossil, do those solar panels sit right on the ground? 
Could they be better served sitting on some rigid foam insulation?
Are you running glycol in the panels?

I am looking to go with a very similar system, especially one that can be worked on and serviced at GROUND level.

Nice system, now I see how you got that username 

EDIT
How are those pool heating panels made? Could they be copied with access to the right materials?


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## Nofossil (Nov 9, 2007)

babalu87 said:
			
		

> Nofossil, do those solar panels sit right on the ground?
> Could they be better served sitting on some rigid foam insulation?
> Are you running glycol in the panels?



The glazed panels are right on the ground. They have fiberglass insulation internally behind the collector surface. The pool heater has a sheet of foil-faced foam board under the top 8' - I'll add more when I get around to it ;-)

I run water in the system, unpressurized. I have a vented reservoir under the deck above the top of the storage tank. Five reasons for not running glycol:

1) It's expensive
2) I'm still dealing with leaks in the panel plumbing
3) The sun angles are pitiful in fall and winter - not much heat to be had.
4) It's a slightly higher viscosity, which would reduce flow.
5) It's toxic

My solar season ended in mid-October - two days before my first wood fire. Once the wood boiler is going, there's no need for solar anyway. Half an hour of wood boiler is more heat than the solar panels could generate in a day, and the tank temps are so hot that the solar panels couldn't add any at all.



> How are those pool heating panels made? Could they be copied with access to the right materials?



The pool panels are extruded polyolefin. Polyolefin as far as I can tell means 'plastic made of whatever we had lying around'. I bought mine off of eBay for $140 including shipping. I contacted the manufacturer, but they had decided to develop their own solar hot water system and were not interested in talking to me. Haven't seen it yet, though.


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## babalu87 (Nov 9, 2007)

Thanks for the input. Whatever system we adopt I will need to go with glycol. If anything, I want it to at least warm the storage tank to take the load off the water heater during winter and it should provide all the hot water we need during the summer season.

I feel a little stupid using the boiler for hot water three seasons running now, what a waste. Its a GREAT way to heat hot water when the boiler is running for heat but other than that its a waste. Especially during heating season.

I already have glass for collectors and I think refrigerator tubing encased in a well insulated panels with everything but the glass painted black will be a start to the system anyway. I plan on having it so I can change the pitch for Summer/Winter sun angles.


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## Nofossil (Nov 9, 2007)

Sounds good. There are a couple of other considerations. If you're going to use a pump, you will need to control the flow rate. Too fast reduces the temperature of the water that you get out of it. A small amount of hot water is more useful than a lot of lukewarm water.

If you're using thermosiphoning, think very carefully about bubbles - they are your enemy. They will collect at any high spot and stop flow. Also, take pains to ensure there are no restrictions. The pressure differential that makes thermosiphoning work is extremely small. Lots of parallel flow paths is much better than a smaller number of paths laid out in series,

Lastly, plan for high temperatures. I've actually boiled water in my panels - see comment on bubbles above. You can burn yourself, and plastic fittings will fail. You will also want to install a tempering valve to ensure you don't get scalding water out of the tap. You also have to plan how to dump excess heat if you don't have a really large storage tank. I heated my 880 gallon storage tank to over 150 degrees with the panels that I have. A smaller tank could lead to boiling in the panels.

Good luck - post pictures and results!


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## thephotohound (Nov 9, 2007)

I am also running an oil fired boiler just for hot water, and it's driving me up a wall. My thought was to also go electric with a super-efficient 40-60 gallon tank (Babs - I live in Central MA, and the total price thru National Grid is around $0.13/kWh incl. delivery charges). Here's my question... when I eventually go solar, can I retrofit any electric tank to fit my solar system?


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## Nofossil (Nov 9, 2007)

ThePhotoHound said:
			
		

> I am also running an oil fired boiler just for hot water, and it's driving me up a wall. My thought was to also go electric with a super-efficient 40-60 gallon tank (Babs - I live in Central MA, and the total price thru National Grid is around $0.13/kWh incl. delivery charges). Here's my question... when I eventually go solar, can I retrofit any electric tank to fit my solar system?



IMHO, the answer is yes. I would use solar to heat a larger tank that can preheat the water going into the existing electric tank. I have another thread that documents what I did for solar hot water. In my case, the domestic hot water tank was an indirect oil fired unit, but the principle is the same.


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## cbrodsky (Nov 9, 2007)

ThePhotoHound said:
			
		

> I am also running an oil fired boiler just for hot water, and it's driving me up a wall. My thought was to also go electric with a super-efficient 40-60 gallon tank (Babs - I live in Central MA, and the total price thru National Grid is around $0.13/kWh incl. delivery charges). Here's my question... when I eventually go solar, can I retrofit any electric tank to fit my solar system?



You can but you won't get as good performance with your solar setup later.

If you're going that way, you might be better off simply buying a solar storage tank up front that includes an electric element.  It's basically a somewhat more expensive highly insulated water heater that includes all the ports you'll need for connection to any type of solar HW system along with a good in-tank heat exchanger that will help optimize your stratification, which is an important part of how well a solar HW system will function.  The solar tanks are usually 80 or 120 gallons.  You can find them online too.

-Colin


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## thephotohound (Nov 9, 2007)

NY Soapstone said:
			
		

> You can but you won't get as good performance with your solar setup later.
> 
> If you're going that way, you might be better off simply buying a solar storage tank up front that includes an electric element.  It's basically a somewhat more expensive highly insulated water heater that includes all the ports you'll need for connection to any type of solar HW system along with a good in-tank heat exchanger that will help optimize your stratification, which is an important part of how well a solar HW system will function.  The solar tanks are usually 80 or 120 gallons.  You can find them online too.
> 
> -Colin



That will probably make even more sense a few more years down the road, as I plan to heat 1000 SF of new construction (all bedrooms) strictly with solar. Is heating this size space just a pipe dream, or possible (for a reasonable price)?


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## Nofossil (Nov 9, 2007)

ThePhotoHound said:
			
		

> That will probably make even more sense a few more years down the road, as I plan to heat 1000 SF of new construction (all bedrooms) strictly with solar. Is heating this size space just a pipe dream, or possible (for a reasonable price)?



Others may have more concrete data, but my observation is that the sun doesn't always shine in New England. I think the 'strictly' part is a pipe dream, but you could certainly reduce the need for other forms of heat. Some sort of storage would be necessary. Our house heats itself via passive solar just fine during the day, but we have to supplementary heat during the night. Remember that nights are longer than days this time of year


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## cbrodsky (Nov 9, 2007)

ThePhotoHound said:
			
		

> NY Soapstone said:
> 
> 
> 
> ...



I think at best, you could supplement your heating needs a little bit but you'd need a very good site for sun exposure with the panels mounted at just the right angles, and would need to plan on radiant heat that runs in the 90s.  Baseboard requires temperatures much higher than what you'll get out of solar in the winter.

In the summer, you'd be so incredibly oversized that you'd have to build yourself one awesome outdoor spa to keep them cool 

The price will also depend greatly on what tax incentives are available, but in general, I don't think you'd find it to be cost effective compared to other options.

-Colin


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## babalu87 (Nov 9, 2007)

A water softener is probably a MUST for a tank HW system.
My well water is hard as a rock and full of minerals but the water softener makes it nicey nice.

If too much heat during the summer is an issue with a solar system couldnt one just cover up a portion of it during that time of the year?


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## cbrodsky (Nov 9, 2007)

enord said:
			
		

> wrong worry
> 4 efficient solar hw u will need another tank at lower temp to efficiently collect solar energy at lower water temp.



That's true if you don't have a true solar HW tank/exchanger system and is an important point to be aware of - it is one of the reasons why the retrofit solar wands that you just stick in the top of your existing tank can't deliver the same results.  You do best by selectively pulling out your coldest water to send it up to the solar panels, and then sending that water back such that it ends up in the hotter portion of your water storage.

However, the Rheem tanks achieve phenomenal temperature stratification within a single (large) tank - regularly maintaining 40-50 degree differences top-to-bottom.  There is a diptube that reaches to the bottom of the tank to draw water for heating and a second shorter diptube that returns it to the top of the tank.  It does this with remarkably little mixing as well, as evidenced by the very large temperature difference you can observe at any given time in the tank.  I'm not sure if they have internal baffles that are somehow assisting this process or not.

-Colin


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## babalu87 (Nov 14, 2007)

Update
After looking through the old oil receipts I find out that we have been burning about 200 gallons of oil per year to heat hot water.
Even at $3.00 a gallon that is probably cheaper than propane or electric.

I am starting to think that a Boilermate and the eventual Solar attached to what we currently have may be the best option. 

Since my sister is in the propane and propane accessories business I know a propane system for a family of four is going to go through 25-30 gallons/month in "Winter" and 15-20/month in the "Summer". 

Wish I knew what an electric hot water tank really used per month.


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## Nofossil (Nov 14, 2007)

babalu87 said:
			
		

> Update
> After looking through the old oil receipts I find out that we have been burning about 200 gallons of oil per year to heat hot water.
> Even at $3.00 a gallon that is probably cheaper than propane or electric.
> 
> ...



I don't know, but that's never stopped me ;-)

First of all, the 15-20 gallon per month number rings true and is very consistent with everything I've seen. Oil is about 130k BTU per gallon. An indirect tank gets heat transferred to it with something like 75% overall efficiency, so at 20 gallons per month you're putting about 2 million BTU into the tank each month. Converting BTU to KWH, that would be somewhere in the 500 to 600 kWh range. (Electric hot water heaters are 100% efficient at turning electricity into heat in the tank)

On-demand heaters are more efficient because they lose less heat to the environment when no hot water is being used.


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## Eric Johnson (Nov 14, 2007)

I put in an electric water heater for summer duty, and I know my electric bills didn't go up by $50 a month. And my girls use some hot water. But it should be an easy calculation to make, given the right information. One way is to look at what it says on the side of the water heater, i.e., "average annual cost of this unit," and so forth.

It pays to remember that an electric water heater is 100 percent efficient, at least as far as energy input is concerned. Nothing goes up the stack and nothing is lost moving water between appliances. No pilot lights, etc., either. That doesn't necessarily make electric a better deal, but it's something to consider. The thing I like about electricity is that the rates are set by the PUC--so they're not going up without a lot of advance notice and a lot of public scrutiny and input. Can't say that about oil or gas, I don't think.

Somewhat OT, I just passed by the local gas station and was shocked to see diesel going for $3.65 a gallon. If that's the trend, the heating oil probably isn't far behind. Not to be a total Liberal, but you'd think the govt. would think about capping the price of home heating oil at some point or people won't have any money left over to pay their taxes come April.

EDIT: Nofo beats me to again. He made my point about efficiency and gave you some numbers to work with. Good man, as usual.


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## Nofossil (Nov 14, 2007)

Eric Johnson said:
			
		

> EDIT: Nofo beats me to again. He made my point about efficiency and gave you some numbers to work with. Good man, as usual.



HA! Fastest post in the east (blows smoke off of index finger).

Right now, electric is almost dead even with oil in terms of cost.

I'd be careful about meddling with the market, whether liberal, fascist, neocon, or fruitarian. We are in a global economy, and we do not set, control, or have much influence over the price of a barrel of crude oil. Limiting the price that can be charged for fuel oil woul have several likely outcomes, few of them good:

1) There would be less incentive for end-users to switch to other alternatives (like wood)
2) If the profit margin is squeezed too much, it will inhibit investment in infrastructure and improvements to the production and distribution.
3) If the cost of crude oil becomes too high relative to the allowable price for the refined product, you will have massive shortages. No one will produce a product at a loss.

Just my $.02


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## Eric Johnson (Nov 14, 2007)

Sorry, I didn't mean to start an Ash Can debate. I disagree with your all-or-nothing, apocalyptic, end-of-civilization-as-we-know-it-if-we-help-some-poor-slob-get-through-the-winter characterization of my proposal, but we can take that up in the Can if we're so inclined.


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## Nofossil (Nov 14, 2007)

Eric Johnson said:
			
		

> Sorry, I didn't mean to start an Ash Can debate. I disagree with your all-or-nothing, apocalyptic, end-of-civilization-as-we-know-it-if-we-help-some-poor-slob-get-through-the-winter characterization of my proposal, but we can take that up in the Can if we're so inclined.



Sorry as well - raw nerve for me. I spend way too much time trying to help companies do the right things despite well-intentioned regulations that make it next to impossible. I also lived through wage and price controls in this country. Not an experiment to be repeated.

I would HEARTILY (watch how I deftly get back on topic) support programs to guarantee loans for alternative energy solutions such as the one this thread is based on. I suspect that there are many installations that would make economic sense in the long run and where the barrier is the up-front cost. If it were easy to do the conversion and pay off the loan with a portion of the savings, we could do a lot of good and not have the same risk of unintended consequences.


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## cbrodsky (Nov 14, 2007)

babalu87 said:
			
		

> Update
> After looking through the old oil receipts I find out that we have been burning about 200 gallons of oil per year to heat hot water.
> Even at $3.00 a gallon that is probably cheaper than propane or electric.
> 
> ...



You've just illustrated why solar HW is generally a very nice investment for people with oil as their current heat source.

You should be able to get a very nice solar thermal system installed for $4,000 that would cover roughly 80% of your annual needs.  (keep in mind large tax credits at fed level and many states)

If you put $4,000 in the bank at 5% in a CD (getting harder to do w/rate cuts) you'll make $200/year to start and then you'll pay tax on that interest income, so you'll probably net out about $120-$160 after taxes, or 3-4% net return.

If you put $4,000 in solar, you'll save about $480 of after-tax income that you no longer spend on oil.  At $3/gallon, you're looking at a 12% net return in your first year.  This will blow away what you could get with any comparable "safe" investment.  The risk involved is that energy costs plummet before you've obtained these savings for the 30 year expected life of the system.  But even then, say oil drops to $1/gallon, you're still making 4% return - probably equal or better than the bank.  And if energy prices increase further, your avoided costs and hence return on investment increase as well.

People on natural gas or in the midwest where electricity is currently cheap often find it doesn't pay off quite so well but it's likely an OK proposition.  For northeasterners on oil, it's a great move.

-Colin


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## Eric Johnson (Nov 14, 2007)

Do you think that kind of long-term investment helps or hurts home resale value? It would be a selling point for me, but I'm probably not the average homebuyer.


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## cbrodsky (Nov 15, 2007)

Eric Johnson said:
			
		

> Do you think that kind of long-term investment helps or hurts home resale value? It would be a selling point for me, but I'm probably not the average homebuyer.



It's a good question - I have seen a couple studies that say you recoup what you put into it, but I suspect that varies tremendously with the price of energy, whether it is a clean professional automatic system vs. homebrewed job, regional attitudes towards "green" energy, current political tilt, what end of the market you're in...  Right now, I'd bet it's a big plus in our area based on those factors.  

California is one market where solar PV may be getting common enough that people can start analyzing purchasing decisions with better comparisons of with/without solar in large neighborhoods where "comp" analyses are easy.

7 years ago when I moved to NY, I didn't put a lot of stock in it when I saw it on one house.  I didn't know any better, there was zero mention of it from the owner or in any of their listing materials to educate me on it, my realtor said oil was $1/gallon (which it was) and that I could heat a house for less than $1000/year including hot water.  Even when we built, I would have made some very different choices up front had I been able to forsee what has happened since with fuel costs.  I admit my ignorance in hindsight 

My lesson from that is at minimum, somewhere in the listing/marketing materials or even at the house itself, I would highlight some of the energy efficient features to get the potential buyer thinking about the added value.  For that matter, I might even consider leaving a brochure w/our average annual energy use figures and suggest buyers ask for the same records from any home they look at.  They would probably be in for a rude awakening in some of our McMansion suburbs in wide open fields where co-workers are paying $500-$1000/month in heating and cooling bills.  I know I would ask for that information, but I'm probably no longer a "typical" buyer from all my hearth.com liberal brainwashing  :lol: 

-Colin


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## Nofossil (Nov 15, 2007)

Eric Johnson said:
			
		

> Do you think that kind of long-term investment helps or hurts home resale value? It would be a selling point for me, but I'm probably not the average homebuyer.



I've long resigned myself to the idea that no 'average' buyer will be interested in my house. When the time comes, I hope that some techie type falls in love with it. It has a ton of things that would be features to some and turn-offs to others.

Until alternative energy systems mature and the support infrastructure comes of age, I think that you can't assume that any of these things will add bankable value.

I have a friend who bought a house a few years back. In passing, she mentioned that it had 'some strange wood furnace' in the basement when they bought it. They never used it, though they did install a very nice designer-approved enamel woodstove on the main floor. Turns out the thing in the basement is a Tarm gasifier, very early model. Unfortunately, I think rust has gotten to it, though I'm going to check it out. The sellers never said anything about  it to them.


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## babalu87 (Nov 15, 2007)

Eric
Electric rates are set and certainly wont fluctuate all that much but are they really as efficient as they say? What about recovery time etc. Coincidentally, the only "hard" data I can find is......................... from propane companies LOL

I will certainly go with some solar but $4K??????????? I can build something for MUCH cheaper.
The real eye opener for me was this year. 
I took most of my showers from one of those solar showers this year. PLENTY hot for sure on sunny days and that is about as simple a system as can be.
Some glass from a crappy slider, a few circulating pumps, some thermostatic controls , some reefer tubing and black paint and I am half way there


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## Eric Johnson (Nov 15, 2007)

What a great avatar, nofo. A friend of mine did that, too.


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## Nofossil (Nov 15, 2007)

Eric Johnson said:
			
		

> What a great avatar, nofo. A friend of mine did that, too.



Thanks. I didn't do this one - just a random picture that I found. I do have a few Saturns parked next to a pair of huge trees that I'm going to be taking down soon. Here's hoping it's not foreshadowing...


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## cbrodsky (Nov 15, 2007)

babalu87 said:
			
		

> Eric
> Electric rates are set and certainly wont fluctuate all that much but are they really as efficient as they say? What about recovery time etc. Coincidentally, the only "hard" data I can find is......................... from propane companies LOL
> 
> I will certainly go with some solar but $4K??????????? I can build something for MUCH cheaper.
> ...



Electric is straightforward - you pay for it after the wires leave your house meter into your house.  Unless you have undersized wiring that is heating up and wasting power, the only place it should ever convert to heat is inside the heater at the electric resistance element.  So 99.99% of the electricity converts to heat in the water - then it's just a matter of how well the tank holds it.  Recovery time, etc doesn't enter the equation - it's just how much of the power goes into the water.  In any fired system, some of the input energy goes up the flue.

A solar storage tank costs ~$800-$1000 for 120 gallons of storage including an internal heat exchanger and backup electric heater element.  Commercial panels run another $1000 or so each and 2-3 is the typical requirement.  Other major expenses are a controller ($100 for a simple barebones one w/no temp display), if you mount on a 2-story roof, a fairly pricey high-head Taco bronze circulator (~$300), and quite a few valves and runs of food-safe tubing (no garden hoses) to interface into your existing system assuming you want flexibility to go between solar only, solar preheating to oil, or complete bypass of solar.

The difference you'll see with the commercial panels is that you get loads of heat even on cloudy days when it's cool outside for at least 8 months a year.  During much of that time, a homebrew system is not going to do much for you.  It will also likely need to be removed if you have to sell your home.  Particularly if you put the stuff out on your lawn running tubes out of your basement window to save on pumps and such 

A system like this:
http://www.kingsolar.com/catalog/mfg/package/ksdb-40.html

is likely to far outperform anything you can homebuild in terms of the length of season that it will produce hot water.  Complete setup using your existing tank runs $2200 before rebates that may cut it to $1000 in some states.

My take on this project is that it is rare you get to have the government pay 55% of the cost of parts and labor for home projects, so when they do, I'm all for it.  On the other hand, since they didn't want to pay for my woodstove/hearth, I took that work on myself.

-Colin


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## Eric Johnson (Nov 15, 2007)

Back when I was seriously considering solar, I came to pretty much the same conclusion, probably with your help, Colin. I started out planning to build something from scratch, but eventually came to the conclusion that it was worth putting some money into good collectors, and then cobbling everything else together myself.

I finally decided to put my meager resources into a new boiler, but it was fun to research and think about a solar project.

When preparing my boiler install, I found that it's a lot of fun to shop for pumps, fittings, valves, etc. on Ebay. If you know what you want and you have some time to wait out the deals, you can get new stuff for a fraction of what you'd pay retail at Home Depot or a plumbing/heating supply house. One main caveat being knowing what you want. Another one is that stuff you buy from a third party on Ebay is probably not going to carry a warranty, at least not one you can claim very long after the sale. My point being that new bronze pumps go for a lot less than $300 on Ebay. A cast iron Taco 007, for example, goes for $30 to $35, and that's with integral flow control, compared to $80 or $90 retail. Copper fittings are available in oddball lots, but if you find one with the parts you need, you'll wind up paying comparably less for them, as well.

By this past spring I knew what I needed, then spent the summer shopping for it online. By August I had everything I needed to do the install the way I wanted. It was a lot of fun, and nice to save money in the process.


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## cbrodsky (Nov 15, 2007)

Eric - 

I in fact got a great deal for my on-demand hot water re-circulator following your suggestion to look on e-bay - $50 instead of the list price of well over $300!  It's amazing what can be found there.

-Colin


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## Eric Johnson (Nov 15, 2007)

I hate to publicize it because I don't want you guys bidding against me, but sometimes I can't help myself. My handle is Oldforge1, btw.


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## babalu87 (Nov 15, 2007)

My thought on solar is even with the best system money can buy where I live is not conducive to a return on a solar investment.
Arizona, Texas, California etc. sure but the SE corner of Massachusetts doesnt get much sunlight during the course of a season with stalled fronts, fog etc. Its almost like trying solar in Scotland.

If I can at least assist my current HW heating system in heating the water to shower temps,I am ahead of the curve. 
Having a storage tank for that hot water will increase the length of my boiler firings making that system more efficient as well.

I'm telling you those solar showers on the back deck were a wake up call. All I did was refill it after using and put it on a deck chair in the back yard, even on partly cloudy days that bag was plenty hot for a summer shower.

I'm not dreaming of full solar hot water, especially in the "Winter" season but just heating the well water to room temperature would be a start.  Heating water from 47 degrees up to 140 degrees eats up A LOT of BTU's 

Not discounting solar and if I had 4K sitting around I might think of it , besides, building things is fun


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## Eric Johnson (Nov 15, 2007)

I think there's a wood-fired boiler in your future, babs.


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## babalu87 (Nov 15, 2007)

No way!
I will never give up the wood stove

I almost bought an outdoor boiler ........ then I found out someone I knew had on in NH and decided that I didnt have enough acreage to feed the monster.


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