|
Home > Archive > Alternative Power sources > November 2006 > to take a home off-grid
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
to take a home off-grid
|
|
| Harry Chickpea 2006-10-29, 1:25 pm |
| I'm looking at a situation where I might take a rural home (hopefully
with a small woodlot) off-grid in southern Tennessee or northern
Alabama, and I'm trying to figure out a good power/heating/cooling
package that would be simple, relatively cost effective, last a
minimum of 25 years and have parts available throughout that timespan
no matter what happens.
"Relatively" cost effective means that I need a humidified warm house
- 75 degrees or over - to tolerate cold weather. This is a health
issue and is non-negotiable. Retrofitting insulation will help some,
but I know that I'll still be spending more on calories of heat than
many homeowners and off-grid folks. When I take into consideration
the costs of heating and hot water, I have to add those costs to power
costs to come up with my true utility costs. If I'm going to be
spending money on heat and a heating system anyway, I might as well
get my electricity out of it as well.
This is what I've come up with so far, ready for tearing apart in
search of flaws.
Hot water from co-gen aided by HAHSA wood heat in winter seems to fit
well with a primarily battery operated system.
FWIW, 1000 gal septic tanks seem to cost about $500 and form a basis
for some energy storage.
I would start with a new construction slab-floored (10' x 24'?) power
shed that formed the north wall of a new similarly sized
greenhouse/sunroom/clothes drying space. The south facing insulated
metal shed roof of the shed would hold some solar panels (both HW and
power, depending on costs) and gutter into a sand filtered 1000 gal
cistern of rainwater for use in gardening, laundry, etc.
Inside the shed are two heavily insulated 1000 gal septic tanks - one
for hot water, one for cold. The cold tank acts primarily as a
reliable water source in case of fire and as a backup storage for well
water, but for the summer months, sensors could chill the water by
running it across the roof on cold nights, with the intent of
rudimentary house cooling (radiator/fan combo in house), and keeping a
pantry/root cellar cool. I realize the AC effect would probably be
marginal, but any free cool breeze in 90 degree weather is welcome.
The hot water tank is more critical, and would get heated from co-gen,
solar, wood, & waste oil, and be brought up to between 150 and 200
degrees during the winter. That water would then be used for subfloor
or baseboard perimeter heating, with a coil or transfer plate for
domestic HW, similar to a HASHA. I'm a little concerned on sizing. I
figure that the heat equiv of about 50 lbs of wood can be effectively
stored in 1000 gals dropping from 200 to 150, which is only a day or
two worth of heat.
Cooking will be via propane or LNG, with a backup water heater in the
power shed that might never be used, or might provide heating
assistance on really cold nights. One house I'm looking at has a wood
stove, but I probably won't use it. I've used wood heat inside a
house before and was always uncomfortable because of real and imagined
fire risks. Other than cooking, I want to avoid flames in the house
as much as possible.
Electric power wants to be redundant. A temperature controlled
battery bank of a minimum of 10 T-105s in the power shed would feed
two inverters- the first, my existing MSW Trace 2012, and the second
being a true sine wave inverter of similar power, to be purchased.
(Suggestions on make and model?) These would provide "running" power
on a constant basis, with the Trace powering the less sensitive loads.
With two converters, even if one goes down in a blizzard, the
situation is not critical.
The battery bank would be charged by some solar, but primarily by a
small efficient engine/altenator combo, using this:
<http://www.balmar.net/page67-ars5.html>
and this:
<http://www.prestolite.com/pgs_produ...resh=1156314564>
However, I'm having a time trying to figure out the best engine to
power this job.
If I went with a small listeroid, it might easily last the 25 years,
but would take a lot of tweaking and time and effort, and have the
characteristic thumping that is hard to damp. A throwaway (5 hp?)
lawnmower engine would be less efficient, noisier, last only a few
years even with coddling, use gas instead of diesel, provide more
waste heat, but be significantly cheaper, to the point that a spare or
two could be kept on site, or the charging system duplicated.
A cheap gas engine would provide the option of being able to run off
the LNG or even wood gas if I got ambitious, and not worry too much
about damaging it beyond repair, but a diesel might run on waste oil
or vegetable oil - decisions. Suggestions?
Since absorption and float charges can take a while, and must be done
at least periodically, another thought I had was of getting an add-on
auto AC kit to heat pump cold into the cold tank and heat into the hot
tank during those low power draw periods of enforced alternator
running, or even use it as a regular AC by placing the evap coil in
the house and the condenser in the cool tank?
Any engine has to either be very quiet, or be capable of being
baffled, since the co-gen and HASHA limit the distance between the
powerhouse and home. That brings in the idea of considering a small
automobile engine that might be quieter, last longer, and do other
tasks as well. Auto engines are manufactured to closer tolerances
than listers or yard work engines, and now outlive many autos, but
what of all the emissions equipment and computer controls? Is there
even a simple small auto engine available any more? Then there is the
question - gas or diesel? - and why?
Any engine will also have to be self-starting when the batteries drain
to a certain level, and know when to shut off, since the idea is to
not damage the batteries and keep maintenance chores to a minimum.
Ideas for companies that make such circuitry?
Larger power needs would be met by a 7 to 10 KW generator head driven
by a larger engine with a significant flywheel. With all the major
power hungry appliances being removed or gas powered, this would
rarely run except if I was working in the shop or had need of a large
AC. I might even delay or skip this and just use a shorter lived
contractor generator instead.
A complete system like this won't be cheap, and will have some ongoing
costs, but I think it might be do-able in stages, and cost-effective
over the lifespan.
How about it? Too ambitious? Too "pie in the sky?" Underestimating
loads?
| |
| George Ghio 2006-10-29, 8:25 pm |
| Insulate. Wood heat/boost hot water. Solar electric. 5 days autonomy
minimum. Diesel battery charger.
How hard is it.
Why is it that Amerkins work so hard to make their lives complicated.
Tell you what, Harry, follow wayne's example, close your eyes and keep
throwing cash at the problem until it goes away.
OTOH, if you want solar power, you could sit down and design a system to
meet your needs. The same applies to all the other problems. Design to
your needs.
Scared of having a flame in the house, my God man, design a heater that
is safe. Suggest you read "The Book of Masonry Stoves Rediscovering an
Old Way of Warming", by David Lyle.
Harry Chickpea wrote:
> I'm looking at a situation where I might take a rural home (hopefully
> with a small woodlot) off-grid in southern Tennessee or northern
> Alabama, and I'm trying to figure out a good power/heating/cooling
> package that would be simple, relatively cost effective, last a
> minimum of 25 years and have parts available throughout that timespan
> no matter what happens.
>
> "Relatively" cost effective means that I need a humidified warm house
> - 75 degrees or over - to tolerate cold weather. This is a health
> issue and is non-negotiable. Retrofitting insulation will help some,
> but I know that I'll still be spending more on calories of heat than
> many homeowners and off-grid folks. When I take into consideration
> the costs of heating and hot water, I have to add those costs to power
> costs to come up with my true utility costs. If I'm going to be
> spending money on heat and a heating system anyway, I might as well
> get my electricity out of it as well.
>
> This is what I've come up with so far, ready for tearing apart in
> search of flaws.
>
> Hot water from co-gen aided by HAHSA wood heat in winter seems to fit
> well with a primarily battery operated system.
>
> FWIW, 1000 gal septic tanks seem to cost about $500 and form a basis
> for some energy storage.
>
> I would start with a new construction slab-floored (10' x 24'?) power
> shed that formed the north wall of a new similarly sized
> greenhouse/sunroom/clothes drying space. The south facing insulated
> metal shed roof of the shed would hold some solar panels (both HW and
> power, depending on costs) and gutter into a sand filtered 1000 gal
> cistern of rainwater for use in gardening, laundry, etc.
>
> Inside the shed are two heavily insulated 1000 gal septic tanks - one
> for hot water, one for cold. The cold tank acts primarily as a
> reliable water source in case of fire and as a backup storage for well
> water, but for the summer months, sensors could chill the water by
> running it across the roof on cold nights, with the intent of
> rudimentary house cooling (radiator/fan combo in house), and keeping a
> pantry/root cellar cool. I realize the AC effect would probably be
> marginal, but any free cool breeze in 90 degree weather is welcome.
>
> The hot water tank is more critical, and would get heated from co-gen,
> solar, wood, & waste oil, and be brought up to between 150 and 200
> degrees during the winter. That water would then be used for subfloor
> or baseboard perimeter heating, with a coil or transfer plate for
> domestic HW, similar to a HASHA. I'm a little concerned on sizing. I
> figure that the heat equiv of about 50 lbs of wood can be effectively
> stored in 1000 gals dropping from 200 to 150, which is only a day or
> two worth of heat.
>
> Cooking will be via propane or LNG, with a backup water heater in the
> power shed that might never be used, or might provide heating
> assistance on really cold nights. One house I'm looking at has a wood
> stove, but I probably won't use it. I've used wood heat inside a
> house before and was always uncomfortable because of real and imagined
> fire risks. Other than cooking, I want to avoid flames in the house
> as much as possible.
>
> Electric power wants to be redundant. A temperature controlled
> battery bank of a minimum of 10 T-105s in the power shed would feed
> two inverters- the first, my existing MSW Trace 2012, and the second
> being a true sine wave inverter of similar power, to be purchased.
> (Suggestions on make and model?) These would provide "running" power
> on a constant basis, with the Trace powering the less sensitive loads.
> With two converters, even if one goes down in a blizzard, the
> situation is not critical.
>
> The battery bank would be charged by some solar, but primarily by a
> small efficient engine/altenator combo, using this:
> <http://www.balmar.net/page67-ars5.html>
> and this:
> <http://www.prestolite.com/pgs_produ...resh=1156314564>
> However, I'm having a time trying to figure out the best engine to
> power this job.
>
> If I went with a small listeroid, it might easily last the 25 years,
> but would take a lot of tweaking and time and effort, and have the
> characteristic thumping that is hard to damp. A throwaway (5 hp?)
> lawnmower engine would be less efficient, noisier, last only a few
> years even with coddling, use gas instead of diesel, provide more
> waste heat, but be significantly cheaper, to the point that a spare or
> two could be kept on site, or the charging system duplicated.
>
> A cheap gas engine would provide the option of being able to run off
> the LNG or even wood gas if I got ambitious, and not worry too much
> about damaging it beyond repair, but a diesel might run on waste oil
> or vegetable oil - decisions. Suggestions?
>
> Since absorption and float charges can take a while, and must be done
> at least periodically, another thought I had was of getting an add-on
> auto AC kit to heat pump cold into the cold tank and heat into the hot
> tank during those low power draw periods of enforced alternator
> running, or even use it as a regular AC by placing the evap coil in
> the house and the condenser in the cool tank?
>
> Any engine has to either be very quiet, or be capable of being
> baffled, since the co-gen and HASHA limit the distance between the
> powerhouse and home. That brings in the idea of considering a small
> automobile engine that might be quieter, last longer, and do other
> tasks as well. Auto engines are manufactured to closer tolerances
> than listers or yard work engines, and now outlive many autos, but
> what of all the emissions equipment and computer controls? Is there
> even a simple small auto engine available any more? Then there is the
> question - gas or diesel? - and why?
>
> Any engine will also have to be self-starting when the batteries drain
> to a certain level, and know when to shut off, since the idea is to
> not damage the batteries and keep maintenance chores to a minimum.
> Ideas for companies that make such circuitry?
>
> Larger power needs would be met by a 7 to 10 KW generator head driven
> by a larger engine with a significant flywheel. With all the major
> power hungry appliances being removed or gas powered, this would
> rarely run except if I was working in the shop or had need of a large
> AC. I might even delay or skip this and just use a shorter lived
> contractor generator instead.
>
> A complete system like this won't be cheap, and will have some ongoing
> costs, but I think it might be do-able in stages, and cost-effective
> over the lifespan.
>
> How about it? Too ambitious? Too "pie in the sky?" Underestimating
> loads?
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Harry Chickpea 2006-10-29, 9:25 pm |
| George Ghio <ghio@nobodyhome.com.au> wrote:
>Scared of having a flame in the house, my God man, design a heater that
>is safe. Suggest you read "The Book of Masonry Stoves Rediscovering an
>Old Way of Warming", by David Lyle.
<shrug> I designed a barrel stove that was even more safe than most
masonry stoves. Still had concerns. Saw too many places burned down,
some with people in them. Not how I plan to go. YMMV.
| |
| George Ghio 2006-10-30, 3:25 am |
| Harry Chickpea wrote:
> George Ghio <ghio@nobodyhome.com.au> wrote:
>
>
> <shrug> I designed a barrel stove that was even more safe than most
> masonry stoves. Still had concerns. Saw too many places burned down,
> some with people in them. Not how I plan to go. YMMV.
More people die in fires started from,
Smoking in bed,
Candles,
Hot oil on the stove,
Electric bar heaters,
than from a properly designed wood stoves used correctly.
Read the book.
--
Posted via a free Usenet account from http://www.teranews.com
| |
| George Ghio 2006-10-30, 3:25 am |
| George Ghio wrote:
> Harry Chickpea wrote:
>
> More people die in fires started from,
>
> Smoking in bed,
>
> Candles,
>
> Hot oil on the stove,
>
> Electric bar heaters,
>
> than from a properly designed wood stoves used correctly.
>
> Read the book.
>
>
Oh yeah, Of the fires started by wood stoves nearly all can be traced
back to operator error.
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Nick Hull 2006-10-30, 9:25 am |
| In article <4545849e$0$12073$88260bb3@free.teranews.com>,
George Ghio <ghio@nobodyhome.com.au> wrote:
> George Ghio wrote:
> Oh yeah, Of the fires started by wood stoves nearly all can be traced
> back to operator error.
Gross operator error. It usually takes several mistakes in a row to get
in trouble. I heated with wood (+solar) for over 20 years and never had
a problem.
--
Free men own guns - www.geocities/CapitolHill/5357/
| |
| Ron Rosenfeld 2006-10-30, 9:25 am |
| On Sun, 29 Oct 2006 19:17:24 GMT, hchickpeaREMOVEME@hotmail.com (Harry
Chickpea) wrote:
>Cooking will be via propane or LNG
In the "spirit" of the net, I'll pick a small nit. "...propane or LNG"
For LNG you'll need a storage tank capable of handling -260°F liquid, and a
regasification setup. Much better off using NG :-))
-- ron (off the grid in Downeast Maine)
| |
| Alan C37 2006-10-30, 9:25 am |
| I cannot comment on most of what you say because my situation is somewhat
different. I have looked hard at reducing my house heating costs, however,
My house is entirely powered from utility electricity and costs over $4000
per year so I have a strong incentive.
My interim (changing often) conclusions are as follows:
1. Far and away the best first thing to invest in is to greatly increase
thermal insulation; air sealing and a good, well filtered heat recovery
ventilation system.
2. Solar heating offers the most efficient, in terms of initial cost and
energy gain, source of home heating. Heat storage can be done as you
suggest but judicious use of thermal mass inside the structure is also well
worth considering. There are many ways in which solar heat can be collected
but some require considerable up-front money. Solar spaces such as often
described by Nick Pine on this and other news groups appear to be the most
cost effective. Thomason trickle down collectors have the advantage of
simplicity. An integral greenhouse which also contains a large insulated
tank for heat storage also appeals to me but is quite expensive to build,
even if you can do most of the work yourself. Reasonably effective thermal
solar panels are available but seem to be too costly for my use here in
Canada since mains electricity is available and still comparatively cheap
(believe it or not!).
3. PV panels are good and useful but much too expensive to provide a large
fraction of my needs. OK as a small back up only I think. This might annoy
some enthusiasts but I consider PV just a hobby for people who do have
access to utility electricity. A good hobby to be sure and if prices can
ever be reduced by about 80% it will become ubiquitous no doubt. It is, of
course, well worth considering if you are going to live somewhere which has
no access to the power lines.
4. One extremely cost effective means of getting heating and cooling is by
the use of reversible heat pumps. These are now very efficient and
inexpensive to buy and install. Perhaps best of all these will give me very
good air conditioning. Much better than my present small window air
conditioners. I will need more than one heat pump but each is only about
$1000 Canadian to buy and a few hundred to install. In really cold climates
they will not provide all the heat needed so some form of what has been well
described as "heavy lifting" heat will be required. Wood fires could do
this but I do so agree with you about the risks of fire in the house. We
had a good wood stove for several years as our main source of heat but we
had two chimney fires which scared the hell out of me so I threw it out.
The fires caused no damage and the double steel chimney survived unharmed.
The fires were my fault as I clearly failed to keep the chimney adequately
cleaned.
The "waste" heat from whatever generators you use could, of course, be
stored in your water tank which would help a lot. In my case "heavy
lifting" is no problem as I already have enough baseboard heaters to keep
the place warm enough at any likely outside temperature.
I have a fairly complex Excel spreadsheet tailored for my situation which
can help calculate the effects of insulation and aid in designing a
structure for thermal solar collection and storage in a greenhouse/garage
structure and will send it if you wish. The first "a" should be changed to
"r." and the obvious bit removed to email me.
Good Luck,
Alan C
"Harry Chickpea" <hchickpeaREMOVEME@hotmail.com> wrote in message
news:4544d450.3783398@news.earthlink.net...
> I'm looking at a situation where I might take a rural home (hopefully
> with a small woodlot) off-grid in southern Tennessee or northern
> Alabama, and I'm trying to figure out a good power/heating/cooling
> package that would be simple, relatively cost effective, last a
> minimum of 25 years and have parts available throughout that timespan
> no matter what happens.
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Pete C. 2006-10-30, 1:25 pm |
| Ron Rosenfeld wrote:
>
> On Sun, 29 Oct 2006 19:17:24 GMT, hchickpeaREMOVEME@hotmail.com (Harry
> Chickpea) wrote:
>
>
> In the "spirit" of the net, I'll pick a small nit. "...propane or LNG"
>
> For LNG you'll need a storage tank capable of handling -260°F liquid, and a
> regasification setup. Much better off using NG :-))
>
> -- ron (off the grid in Downeast Maine)
Yea, but you get a really good energy density for storage. Can probably
get your air conditioning and refrigeration from the re-gasification
part too.
Pete C.
| |
| Harry Chickpea 2006-10-30, 1:25 pm |
| Nick Hull <nhull@isp.com> wrote:
>In article <4545849e$0$12073$88260bb3@free.teranews.com>,
> George Ghio <ghio@nobodyhome.com.au> wrote:
>
>
>Gross operator error. It usually takes several mistakes in a row to get
>in trouble. I heated with wood (+solar) for over 20 years and never had
>a problem.
When I lived in New England, I heated primarily with wood for about
six years and never had a major problem either. But... I still hated
the bark chips and crud in the house, didn't enjoy the choice between
regular care and feeding of the stove or large temperature
fluctuations, disliked the cold or cool exterior walls, skin-cracking
dryness, and concern about leaving fires unattended.
I could do all that again if I had to, but I _choose_ to avoid it if
possible and practical. Back then, it was a choice of dire necessity
when oil prices went through the roof and supplies were limited. I
didn't have the money to do much more than build my barrel stove, get
a few lengths of metalbestos and install everything myself. Now, it
looks like I might have the funds and experience to do the job
properly in a milder climate, and end up ahead of the curve.
Building a new shed avoids the costs and mess of ripping apart a house
to install a costly heavy masonry stove that will still have many of
the same issues that I'm trying to avoid. It also doesn't diminish
usable space, or create a situation where a fire or code inspector can
come in and start to demand changes or upgrades. It also avoids some
insurance issues as well.
As for all house fires being "operator error," I disagree. A large
portion of them are caused by poor design and age deterioration. The
cement in a chimney liner can fail, leaving a gap for the next chimney
fire to use, Ashley stoves were famous for burning out the sheet metal
over time, etc.. Combinations of small flaws can create large
problems.
| |
| Harry Chickpea 2006-10-30, 1:25 pm |
| "Alan C37" <acombellack@nspmsympatico.ca> wrote:
> I cannot comment on most of what you say because my situation is somewhat
>different. I have looked hard at reducing my house heating costs, however,
>My house is entirely powered from utility electricity and costs over $4000
>per year so I have a strong incentive.
> My interim (changing often) conclusions are as follows:
>1. Far and away the best first thing to invest in is to greatly increase
>thermal insulation; air sealing and a good, well filtered heat recovery
>ventilation system.
I agree, and you'll note that insulation was one of the first things I
mentioned. The heat recovery ventilation might be a little less
important in the milder climate, and expecially so with an older house
that is bound to have some infiltration.
>2. Solar heating offers the most efficient, in terms of initial cost and
>energy gain, source of home heating. Heat storage can be done as you
>suggest but judicious use of thermal mass inside the structure is also well
>worth considering. There are many ways in which solar heat can be collected
>but some require considerable up-front money. Solar spaces such as often
>described by Nick Pine on this and other news groups appear to be the most
>cost effective.
Good point. Obviously that will depend on the individual location.
One thing I'm noticing is that most of the houses in the area are
built with crawl spaces rather than full basements or slabs. Crawl
spaces are notorious for wasting energy and being a PITA.
>Thomason trickle down collectors have the advantage of
>simplicity. An integral greenhouse which also contains a large insulated
>tank for heat storage also appeals to me but is quite expensive to build,
>even if you can do most of the work yourself. Reasonably effective thermal
>solar panels are available but seem to be too costly for my use here in
>Canada since mains electricity is available and still comparatively cheap
>(believe it or not!).
That is the pricing issue that stops most folks. Thermal solar is
high enough in cost that the low costs of ongoing electricity make
more sense, especially for people who think they might have to move.
>3. PV panels are good and useful but much too expensive to provide a large
>fraction of my needs. OK as a small back up only I think. This might annoy
>some enthusiasts but I consider PV just a hobby for people who do have
>access to utility electricity. A good hobby to be sure and if prices can
>ever be reduced by about 80% it will become ubiquitous no doubt. It is, of
>course, well worth considering if you are going to live somewhere which has
>no access to the power lines.
I agree that unless you spend the money on a lot of them, and the
other required components, they are more suited to charging a camp
over a week for weekend use, or other similar intermittent uses.
>4. One extremely cost effective means of getting heating and cooling is by
>the use of reversible heat pumps. These are now very efficient and
>inexpensive to buy and install. Perhaps best of all these will give me very
>good air conditioning. Much better than my present small window air
>conditioners. I will need more than one heat pump but each is only about
>$1000 Canadian to buy and a few hundred to install.
We use a high efficiency heat pump in our current house, and the
climate is warm enough that I've removed the heat strips that might
otherwise kick in on cold days. I've been very happy with it overall,
but it does use enough power that it would be impractical for the type
of situation I'm considering.
>In really cold climates
>they will not provide all the heat needed so some form of what has been well
>described as "heavy lifting" heat will be required. Wood fires could do
>this but I do so agree with you about the risks of fire in the house. We
>had a good wood stove for several years as our main source of heat but we
>had two chimney fires which scared the hell out of me so I threw it out.
>The fires caused no damage and the double steel chimney survived unharmed.
>The fires were my fault as I clearly failed to keep the chimney adequately
>cleaned.
I wasn't terribly concerned about chimney fires. The thimble I made
for the metalbestos had about four times the minumum required
clearance, and the roof flashing was similarly overdesigned. My stove
design was also unique, that I could safely pour water into the stove
to damp a blaze and steam out a chimney fire.
> The "waste" heat from whatever generators you use could, of course, be
>stored in your water tank which would help a lot. In my case "heavy
>lifting" is no problem as I already have enough baseboard heaters to keep
>the place warm enough at any likely outside temperature.
> I have a fairly complex Excel spreadsheet tailored for my situation which
>can help calculate the effects of insulation and aid in designing a
>structure for thermal solar collection and storage in a greenhouse/garage
>structure and will send it if you wish. The first "a" should be changed to
>"r." and the obvious bit removed to email me.
My email is active, just remove the obvious capitalized letters. I'd
like to take a look at the spreadsheet, as long as there are no macros
or VBA in it.
> Good Luck,
> Alan C
Thanks
| |
| Harry Chickpea 2006-10-30, 1:25 pm |
| "Pete C." <aux3.DOH.4@snet.net> wrote:
>Ron Rosenfeld wrote:
>
>Yea, but you get a really good energy density for storage. Can probably
>get your air conditioning and refrigeration from the re-gasification
>part too.
>
>Pete C.
LOL! Yeah, that's the ticket.
| |
| nicksanspam@ece.villanova.edu 2006-10-30, 1:25 pm |
| Harry Chickpea <hchickpeaREMOVEME@hotmail.com> might...
>... take a rural home off-grid in southern Tennessee or northern Alabama,
>and... figure out a good power/heating/cooling package that would be simple,
>relatively cost effective, last a minimum of 25 years and have parts
>available throughout that timespan no matter what happens.
What's the cost of grid electricity? Taking it off might be more expensive
and less reliable than leaving it on and adding PVs and a grid-tie inverter
or a few batteries. Grid-tie cogen might cost less.
John Stauffer rebuilds these $975 20 HP water-cooled diesels:
http://cgi.ebay.com/Diesel-Power-un...1QQcmdZViewItem
He'll add a 15 HP induction motor for about $500. He's putting one system
on a trailer so he can "zero out" his electric meter, then tow it to his
father's house and zero out his meter, then tow it to his sister's house and
zero out her meter... but he doesn't use the heat. He says it's very simple
to start the diesel with the grid-excited motor, then crank the meter
backwards, with no special sync circuitry. It might work off-grid with
the field excited with an inverter. You might also zero the meter with
an air-cooled Honda EU2000 and a few extra parts, but it's harder to
recover the heat that way.
>... I need a humidified warm house - 75 degrees or over - to tolerate
>cold weather.
Maybe one that can be made airtight for efficient winter humidification
and summer AC. Add exterior insulation to a block house?
NREL says 750 Btu/ft^2 of sun falls on the ground and 1020 falls on
a south wall in Huntsville on an average 38.8 F January day
with a 48.2 daily max...
>Hot water from co-gen aided by HAHSA wood heat in winter seems to fit
>well with a primarily battery operated system.
Wood is work. HAHSA stoves are dirty. Trojan says a T-105 can store 400 kWh
over its lifetime (500 for fewer deep cycles and 300 for more shallow cycles),
so if it costs $80, that's 20 cents/kWh, just for the batteries.
>... 1000 gal septic tanks seem to cost about $500 and form a basis
>for some energy storage.
If they last 25 years and store 1000x8.33(200-150) = 416.5K Btu (122 kWh)
every day, that's $500/(25x365.25x122) = $0.00045/kWh, 450X cheaper than
batteries :-) Our local precast place won't guarantee above-ground
concrete tanks against leaks.
>I would start with a new construction slab-floored (10' x 24'?) power
>shed that formed the north wall of a new similarly sized
>greenhouse/sunroom/clothes drying space.
You might build a whole house on cheap off-grid land. With 26 20'x8'x6"
US R24 SIPs and just a few windows and air leaks, a 40'x60' house would
have 2400ft^2/R24 = 100 Btu/h-F for the ceiling + 1600ft^2/R24 = 67 for
the walls, so it could be 75 F for 12h and 65 F at night on an average
January day with about 24h(70F-38.8F)167 = 125K Btu. If 68K comes from
600 kWh/mo of electrical use, it needs 57K Btu/day of additional heat.
A $1 square foot of R1 polycarbonate siding with 90% solar transmission
might gain 918 Btu and lose 6h(130F-44F)1ft^2/R1 = 516 on an average day,
for a net gain of 402, so you might heat the house above with 57K/402
= 142 ft^2 of solar siding, eg an 8' tall x 20' long thermosyphoning air
heater over an air gap over a dark south wall.
If the air heater keeps the house warm for 6 hours per day, you might
store 57Kx18h/24h = 43K Btu of overnight heat in C pounds of water under
the ceiling that warms to 120 F by dusk and cools to 70 F by dawn, where
C = 43K/(120-70) = 855 pounds, eg 16 4"x10" PVC water pipes or 2 4'x8'
platforms with 2.6" flat polyethylene water-filled ducts on top.
You might store 5x57K = 285K Btu of heat for 5 cloudy days in a row in
285K/(170-80) = 3167 pounds (51 ft^3) of water cooling from 170 to 80 F
in a 4'x8'x2' deep EPDM-lined plywood tank on the ground with a good
greywater heat exchanger and a pressurized copper pipe coil in the tank
for domestic hot water.
>The south facing insulated metal shed roof of the shed would hold
>some solar panels (both HW and power, depending on costs) and gutter
>into a sand filtered 1000 gal cistern of rainwater for use in gardening,
>laundry, etc.
Huntsville gets an average 3.25" of rain in October (the driest month.)
You might concentrate 2-3 suns down on to horizontal PV panels covered
with poly film water ducts to reduce the cost and collect useful heat.
>Inside the shed are two heavily insulated 1000 gal septic tanks - one
>for hot water, one for cold. The cold tank acts primarily as a
>reliable water source in case of fire and as a backup storage for well
>water, but for the summer months, sensors could chill the water by
>running it across the roof on cold nights, with the intent of
>rudimentary house cooling (radiator/fan combo in house), and keeping a
>pantry/root cellar cool. I realize the AC effect would probably be
>marginal, but any free cool breeze in 90 degree weather is welcome.
Huntsville is humid in July, with w = 0.0155 pounds of water per pound
of dry air and 68.9 F min and 79.0 24-hour average temperatures. Night
ventilation with a small AC for dehumidification or a slow ceiling fan
can make an airtight house comfy.
Good luck,
Nick
| |
| Trygve Lillefosse 2006-10-30, 5:25 pm |
| On Mon, 30 Oct 2006 02:28:34 GMT, hchickpeaREMOVEME@hotmail.com (Harry
Chickpea) wrote:
>George Ghio <ghio@nobodyhome.com.au> wrote:
><shrug> I designed a barrel stove that was even more safe than most
>masonry stoves. Still had concerns. Saw too many places burned down,
>some with people in them. Not how I plan to go. YMMV.
Make a well insulated shed, with concrete wall facing the house. Be
sure that there are open space around it(no trees/scrubs). Then
install an automatic wood-chip stove.
That should take away(read:minimize) any possible fire-hazards.
I think it makes sense to use wood. As long as you have a plot with
some trees/forrest. You will probarbly want to thin it out a bit
anyway, and it's free energy just outside your doorsteps.
--
SEE YA !!!
Trygve Lillefosse
AKA - Malawi, The Fisher King
| |
| Trygve Lillefosse 2006-10-30, 5:25 pm |
| On Mon, 30 Oct 2006 09:20:08 -0500, "Alan C37"
<acombellack@nspmsympatico.ca> wrote:
>4. One extremely cost effective means of getting heating and cooling is by
>the use of reversible heat pumps. These are now very efficient and
>inexpensive to buy and install. Perhaps best of all these will give me very
>good air conditioning. Much better than my present small window air
>conditioners. I will need more than one heat pump but each is only about
>$1000 Canadian to buy and a few hundred to install. In really cold climates
>they will not provide all the heat needed so some form of what has been well
Hi there.
I am just about to buy an air to air heatpump. But the prices here in
Norway starts at cad$1400.
I want to install it myself, using a wacum pump and some presision.:-)
(Possibly using an installer if I get cold feets.)
Anyway. I was wondering if you could lead me to canadian webstores
selling theese units.
BTW: I recon that they will have defrosting capabilities, are
inverter models and run at 240V. Could you confirm this?
--
SEE YA !!!
Trygve Lillefosse
AKA - Malawi, The Fisher King
| |
|
| On Sun, 29 Oct 2006 19:17:24 GMT, hchickpeaREMOVEME@hotmail.com (Harry
Chickpea) wrote:
>I'm looking at a situation where I might take a rural home (hopefully
>with a small woodlot) off-grid in southern Tennessee or northern
>Alabama, and I'm trying to figure out a good power/heating/cooling
>package that would be simple, relatively cost effective, last a
>minimum of 25 years and have parts available throughout that timespan
>no matter what happens.
A general recommendation - If you're going to have a lot of systems,
then making them passive rather than active might be a good overall
strategy. For instance, Nick Pine has mentioned a sort of umbrella
foundation insulation scheme, might be worth looking into.
>The battery bank would be charged by some solar, but primarily by a
>small efficient engine/altenator combo, using this:
><http://www.balmar.net/page67-ars5.html>
>and this:
><http://www.prestolite.com/pgs_produ...resh=1156314564>
I use a similar alternator, but only for occasional backup. For more
frequent use, something more efficient is probably needed. Have you
seen these? http://www.hydrogenappliances.com/pmacurves.html You
might also consider using a Honda EU series feeding the generator
input of an Outback FX. That combination would give you a charge every
time you run the generator. You could even switch between a large and
small generator as needed.
>However, I'm having a time trying to figure out the best engine to
>power this job.
I used a larger engine, and geared it for lower revs. 14hp, perhaps
2500 rpm, about .4 gallons per hour at 2000W. As I said, not something
you'd want to do as a primary source.
> provide more
>waste heat,
If you're burning more fuel than needed for electric just to get the
waste heat, then I think you'd be better off with a furnace.
>Larger power needs would be met by a 7 to 10 KW generator head driven
>by a larger engine with a significant flywheel. With all the major
>power hungry appliances being removed or gas powered, this would
>rarely run except if I was working in the shop or had need of a large
>AC.
I'd go crazy if I had to start a generator for every large load.
They're often of short duration (low energy), so it makes more sense
to start with large inverters IMO, especially now that the Outback
series can come online as needed, without penalty except for the
initial cost.
Wayne
| |
| Alan C37 2006-10-31, 9:25 am |
|
"Trygve Lillefosse" <trygve@lillefosse.NOSPAM.org> wrote in message
news:56mck2puv69a46baaj3lune51t72vagvo0@4ax.com...
> On Mon, 30 Oct 2006 09:20:08 -0500, "Alan C37"
> <acombellack@nspmsympatico.ca> wrote:
>
> Hi there.
>
> I am just about to buy an air to air heatpump. But the prices here in
> Norway starts at cad$1400.
>
> I want to install it myself, using a wacum pump and some presision.:-)
> (Possibly using an installer if I get cold feets.)
>
> Anyway. I was wondering if you could lead me to canadian webstores
> selling theese units.
>
> BTW: I recon that they will have defrosting capabilities, are
> inverter models and run at 240V. Could you confirm this?
>
> --
> SEE YA !!!
> Trygve Lillefosse
> AKA - Malawi, The Fisher King
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Alan C37 2006-10-31, 9:25 am |
| Probably the best ones I have found are made by Mitsubishi but these tend
to be expensive when shipping to Canada is included. I have decided on an
18000 Btu/hr system from AirLux and will probably buy it (them) from these
people in BC (shipping to Ontario is quoted at only $70).
http://cgi.ebay.ca/ws/eBayISAPI.dll...AMEWA%3AIT&rd=1
This is an eBay sale which has expired but the page should give you any
links you need. This is a 12000 Btu unit but an 18000 Btu/hr model will
soon be available I understand.
AirLux have a good web site, which I have lost, but no doubt Google can
find it for you. They show the full specifications of their equipment.
We need to have at least a formal inspection done by a "qualified" person
and a local engineer will do this and the installation for me for about
$200. Not too bad.
As far as I remember the units do run on 220/240 volts.
Alan C
"Trygve Lillefosse" <trygve@lillefosse.NOSPAM.org> wrote in message
news:56mck2puv69a46baaj3lune51t72vagvo0@4ax.com...
> On Mon, 30 Oct 2006 09:20:08 -0500, "Alan C37"
> <acombellack@nspmsympatico.ca> wrote:
Hi there.
>
> I am just about to buy an air to air heatpump. But the prices here in
> Norway starts at cad$1400.
>
> I want to install it myself, using a wacum pump and some presision.:-)
> (Possibly using an installer if I get cold feets.)
>
> Anyway. I was wondering if you could lead me to canadian webstores
> selling theese units.
>
> BTW: I recon that they will have defrosting capabilities, are
> inverter models and run at 240V. Could you confirm this?
>
> --
> SEE YA !!!
> Trygve Lillefosse
> AKA - Malawi, The Fisher King
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Trygve Lillefosse 2006-10-31, 1:25 pm |
| On Tue, 31 Oct 2006 09:46:58 -0500, "Alan C37"
<acombellack@nspmsympatico.ca> wrote:
> Probably the best ones I have found are made by Mitsubishi but these tend
>to be expensive when shipping to Canada is included. I have decided on an
>18000 Btu/hr system from AirLux and will probably buy it (them) from these
>people in BC (shipping to Ontario is quoted at only $70).
>http://cgi.ebay.ca/ws/eBayISAPI.dll...AMEWA%3AIT&rd=1
Thanks for the info. Greatly apreciated.
--
SEE YA !!!
Trygve Lillefosse
AKA - Malawi, The Fisher King
| |
|
|
|
|
|