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SUMMARY: solar house design in cloudy climates (Seattle) Part I
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Subject: SUMMARY: solar house design in cloudy climates (Seattle) Part I
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From: jallred@spdg.com (John Allred)
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Date: Mon, 10 Oct 1994 22:31:22 GMT
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Article: 12562 of misc.rural
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l: 12562
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Newsgroups: sci.energy, misc.consumers.house, misc.rural
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Organization: /usr/lib/news/organi[sz]ation
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Xref: bigblue.oit.unc.edu sci.energy:25290 misc.consumers.house:66581 misc.rura
Well, my mailbox has overflowed with requests (100+) for the summary,
so I'll post it instead. The summary is in two parts, due to its size.
Thanks to all that responded! I received several good pieces of
information, a couple of good references, and one theoretical but very
useful "test" for learning about solar house thermodynamics, which is
in part II.
John
----
Part I:
I asked:
I'd like to talk with people who have designed and lived in solar-powered
houses (Photovoltaics for electricity, passive design for heating) in
sun-poor areas.
Here in the Seattle area we often have to deal with a low stratus
overcast for many weeks during fall, winter, and spring. Obvious ways
to deal with this reduced sunshine level are:
1. super-insulation (to keep as much of the solar heating in the
house as we can)
2. larger than average south-facing glass area (to collect more
solar energy when the sun is shining) (this is somewhat in conflict
with point 1)
3. bigger than average thermal mass (to store more of the
available solar energy)
4. A good, independent backup heat source (eg, woodstove)
Similarly, we can deal with the photovoltaic problems:
1. a bigger PV array
2. more battery storage
3. more efficient appliances, lights, and inverters
4. a good backup generator or complementary power source (eg,
wind turbine), or, dare I say it, grid power
I'm curious what people have learned in this kind of situation. I'm
particularly interested in the tradeoffs used -- for instance, did you
find that super-insulation was more effective and efficient than more
thermal mass? What would you have done differently, now that you've
built the house?
We're planning on building an off-the-grid house on one of the San
Juan Islands (in Northwest Washington State, almost within spitting
distance of Victoria, BC.) Power from a utility is not available on
some of the smaller islands.
Information on how to beat the brain-damaged Washington State Energy
Code (which sees windows as energy losing devices only) would also be
appreciated.
Thanks in advance,
John
----
the responses:
----
In article <CwI6M6.tA@spdg.com>, John Allred <jallred@spdg.com> wrote:
>I'd like to talk with people who have designed and lived in solar-powered
>houses (Photovoltaics for electricity, passive design for heating) in
>sun-poor areas.
I can't speak from experience, but I have done some research into
alternative power sources out of personal interest.
It turns out that solar (photovoltaic) power is very expensive on a
per-watt basis. Here you are talking about kilo-dollars to provide
kilo-watts of power.
If there is any possibility, you should consider construction of a water
wheel (unfortunately only possible near a stream or river) or a wind
generator.
With enough wind or water, a home brew system can power a home for a
couple of hundred dollars (or at most a few thousand). You will of
course need battery backup during the 'dead' times, and that system
will require maintenance.
The following book provides some practical details on some home brew
systems:
Pierson, R.E.. Technician's and experimenter's guide to using sun,
wind, and water power. 1978. 621.3124/P62t 168434F
isbn 0-13-898601-0
Good luck,
----
>In article <CwI6M6.tA@spdg.com>, John Allred <jallred@spdg.com> wrote:
>
>>I'd like to talk with people who have designed and lived in solar-powered
>>houses (Photovoltaics for electricity, passive design for heating) in
>>sun-poor areas.
>The following book provides some practical details on some home brew
>systems:
>Pierson, R.E.. Technician's and experimenter's guide to using sun,
> wind, and water power. 1978. 621.3124/P62t 168434F
> isbn 0-13-898601-0
Also contact The University of Tennessee, Energy Environment and Resources
Center. 615-974-4251. They did extensive experimentation with such things
back in the late 70s and early 80s, including building a number of houses.
I think they're still at it.
----
A lot of factors are involved in going off the grid.
As far as overcast in Northwest, etc. there is a fine
example of a fellow in Coos Bay Oregon, a very overcast
place, who built a very simple solar collection panel
on this roof and heated his house the entire winter, after
a series of engineers told him it could never be done
in that Northwester climate.
That was over 20 years ago.
Building inspectors and neighbors often do not like some
of the solar designs if they look "odd" since the former
can't find it in their rules book and the latter are
forever worried about their property values.
As for photo-voltaics, I don't have a lot of info
on using them in the Northwest, but the cost which
has been coming down steadily on solar panels, is
a big factor...for instance covering a normal size
house roof in solar panels used to cost 10,000
dollars or more...
Personally I like the idea of putting the family
dog in a large rotating drum attached to a
generator but I've always been a little
strange.
cheers
----
I have a passive solar home, an A-frame, and am very pleased with how
it turned out. The thermal mass heated during the day is a red quarry
tile floor, which stays warm most of the evening. Mornings can be
cool, so that's when we use (an approved) wood stove. We usually let
it go out by 9 or 10 AM unless it is constantly cloudy and cold. R30 or
greater insulation is a must everywhere, even in the basement. The only
thing we would do differently is not have a lot of skylights. We really
lose radiant heat through them. Of course some heat is lost through
large window area, but the heat gain on even a partly sunny day exceeds
the loss by more than five to one if it is thermal pane (expensive)
glass. That's the green-house effect working for you.Also, to avoid
the heat of the summer sun, we designed the overhang of the roof to
provide complete shade through most of June and July.
Bottom line is; between using the wood stove and solar heat we never
use our (required) alternative heat source, electric forced air.
Be warned - passive solar heat does not count as an alternative heat
source in many building areas, so you will have to consider at least
installing propane or oil heating even if you almost never use it.
Our electric usage is primarily hot water and lighting. I've considered
using photocells and batteries for lighting, but the real energy
consumer is the hot water heater. A roof mounted solar water heater
would help a little, but were too expensive given the small return.
Here's something to consider regarding using solar power: Heat requires
considerable power for long periods of time. Fortunately infrared
radiation can provide heat gain even on cloudy days because it can
penetrate water droplets. Photocells, however, are most efficent in the
blue and ultraviolet part of the spectrum, and is very attenuated by
cloudy weather. Luckily, electrical power for lighting is only needed
for short periods, so the cost is worth it.
Good luck with your solar powered home -
----
hmmm... spitting distance of victoria...
Waldron Island, perhaps?
Seattle's not a great place for solar... i seem to remember (from 15 years
ago) that it was below the break-even line for total insolation vs. climate.
The island may be different enough climate (you're out of the Puget Sound
convergence Zone, but that can be both a boon and a bane...).
Have you over-wintered on the island yet? The Fraser River dumps rather
chilly air there during the coldest part of the year.
although the -air- temperature stays relatively mellow throughout the year
(due to the thermal mass of the Sound), look to the wall of hills just north
of Vancouver (like Grouse Mtn)... they keep their south-face fairly snowy
quite a ways into the summer... sometimes all the way thru... and that's
only 3k feet or so...
today's more-or-less equinox... were you on the island near summer solstice?
mark where the sun set as an angle north-of-due-west.
now figure an approximately equal angle -south- of due west.
that's about where it'll set in mid-december...
at 3pm local time (roughly), less a bit for the mountains on the peninsula
blocking it.
here -in- seattle we can negotiate additional window area by exceeding
energy guidelines in other areas.. (so my architect tells me).. such
as installing solar storage mass and making the walls over-spec R-rated.
i wish you well, and good luck... keep us posted on how it's going
(i drop into Waldron about once or twice a year to visit friends)
----
I'm not an expert on this subject but I did dabble in the solar industry a few
years ago. I sold solar water heaters in the Toronto area.
Anyway... I would suggest you contact Melinda or Ezra Auerbach of Energy
Alternatives. They live and work on Lasqueti Island in B.C. and are completely
off grid. They specialize in the "alternative lifestyle" that you are talking
about.
They can be reached at 604-333-8898 or by mail at Morewater Road, Lasqueti
Island, B.C., Canada, V0R 2J0. I don't know if they are set up for E-mail.
----
Caveats: I've not done it.
I would suggest that the net heat gain from windows in that cloudy a
climate isn't a viable proposition. On the days it is sunny, it's
probably warm enough that you don't particularly need heat.
Suggest that you go the super-insulation, and heat with wood, and just
do what you can by putting most of your windows on the s. side.
For PV, that's a lot tougher. Suggest that you get a small panel, hook
it up, and meter it to find out realisitically how much power you are
going to get. I'd think in the islands that wind would be a cheaper
alternative.
----
Just thought I'd put in my "inexperienced" 2 cents and ask to post back any
interesting thinks you might find out in this matter.
>I'd like to talk with people who have designed and lived in solar-powered
houses (Photovoltaics for electricity, passive design for heating) in
sun-poor areas.
>From everything I've seen passive solar in the only way to go for
heating/cooling and actually works very well.
A low tech generator may be the best thing for electricity if you can get
propane. Someone may even make a gas fired heating system (for water and
air) does has a generator.
>Here in the Seattle area we often have to deal with a low stratus
overcast for many weeks during fall, winter, and spring. Obvious ways
to deal with this reduced sunshine level are:
1. super-insulation (to keep as much of the solar heating in the
house as we can)
2. larger than average south-facing glass area (to collect more
solar energy when the sun is shining) (this is somewhat in conflict
with point 1)
3. bigger than average thermal mass (to store more of the
available solar energy)
4. A good, independent backup heat source (eg, woodstove)
all good ideas. also consider an air exchanges if things are really air
tight.
>Similarly, we can deal with the photovoltaic problems:
1. a bigger PV array
2. more battery storage
3. more efficient appliances, lights, and inverters
4. a good backup generator or complementary power source (eg,
wind turbine), or, dare I say it, grid power
3 goes without saying, if you can get on the grid at a reasonable $$ (what
are the cost in the islands? -- I would be interested to know) why not --
just be ready to deal with outages (I assume that's a problem?) and the
generator should be just fine (be sure to fire it up occasionally).
>I'm curious what people have learned in this kind of situation. I'm
particularly interested in the tradeoffs used -- for instance, did you
find that super-insulation was more effective and efficient than more
thermal mass? What would you have done differently, now that you've
built the house?
no experience here...
>We're planning on building an off-the-grid house on one of the San
Juan Islands (in Northwest Washington State, almost within spitting
distance of Victoria, BC.) Power from a utility is not available on
some of the smaller islands.
>Information on how to beat the brain-damaged Washington State Energy
Code (which sees windows as energy losing devices only) would also be
appreciated.
Add windows later (unbeknownst to them). Also, if you put thermal shutters
on them will they let you use more? There are automatic systems, and a plus
during storms.
And of course have a computer control everything and use it to gather stats
and ration (warn you of doing stupid things) power reserves if things get
nasty.
----
I read your posting about solar power for a house in the San Juan
islands and thought that your prospects may not be as bad as you paint.
I've spent a lot of time on North Pender Island across the border and my
parents live on Gabriolla. That area has much better weather than either
Vancouver or Seattle so your solar plans may be less of a challenge than you
think.
----
I think Seattle and Binghamton, NY run neck and neck on
lack of sunshine. I read a lot of solar stuff, though.
You list of ideas is good with a few comments:
Windows need insulating shutters since they will
only collect passive solar energy 10-30% of the
time in such overcast climates.
Watch out for having so much thermal mass that
it abosorbs so much heat that the mass (and your
rooms) never warm up much at all.
Best of luck to you. There is always some way to
get benefit from solar energy. Work at it and you
will find something.
----
I thought some of you might be interested in this. It is from an
alternate energy mail list. someone asked for sources of plans for
solar houses.
Here is a list of sources for houseplans that incorporate solar and energy
efficiency features from my files:
SOURCES OF STOCK ENERGY EFFICIENT AND SOLAR HOME PLANS
American Solar Energy Society
2400 Central Ave., G-1
Boulder, CO 80301 HUD User
(303) 443-3130 P.O. Box 6091
Rockville, MD 20850
Carolinas Concrete Masonry (800) 245-2691
Assn.
1 Centerview Dr. Suite 112 Kentucky Division of Energy
Greensboro, NC 27407 691 Teton Trail
(919) 852-2074 Frankfort, KY 40601
(502) 564-7192
Drawing-Room Graphic
Services, Ltd. Passive Solar Environments
Box 88627 821 W. Main St.
North Vancouver, BC Canada Kent, OH 44240
V71 4L2 (216) 673-7449
(604) 689-1841
Small Homes Council
Energetic Design, Inc. Building Research Council
P.O. Box 4446 University of Illinois-Urbana
Greensboro, NC 27404 No. 1 East St. Mary's Rd.
(919) 272-4660 Champaign, IL 61820
(217) 333-1801
Energy Efficient Builder's
Assn., Inc. Home Building Plan Services,
North Central Technical Inc.
College 2235 NE Sandy Blvd.
1000 Campus Dr. Portland, OR 97232
Wausau, WI 54401 (503) 234-9337
(715) 675-6331
Solar Home Plan Book
Florida Solar Energy Center Northeast Utilities
300 State Rd.401 Box 270
Cape Canveral, FL 32920 Hartford, CT 06101
(407) 783-0300 (203) 665-5000
(800) 545-0663
Garlinghouse Co.
P.O. Box 1717 Southface Energy Institute
Middletown, CT 06457 P. O. Box 5506
(203) 632-0500 (in CT) Atlanta, GA 30307
(800) 235-5700 (outside CT) (404) 525-7657
Special Places
Home-Planners, Inc. P. O. Box 9711
3275 W. Ina Rd. Suite 110 New Haven, CT 06536
Tucson, AZ 85741 (203) 498-0818
(800) 521-6797
(800) 322-6797 Sunterra Homes, Inc.
(602) 297-8200 132 NW Greenwood Ave.
Bend, OR 97701
HomeStyles Publishing & (503) 389-4733
Marketing
275 Market St., Suite 521
Minneapolis, MN 55405
(612) 338-8195
----
One of the very best places to find info on passive solar design and
siting is the Ecotope Group located right there in Seattle.
Thanks to the climate in the Northwest, I think we've got the world's
experts on passive solar design for cloudy regimes. There are quite a
few folks in Portland who specialize in passive solar house and commercial
building design, and the U of O architecture department has a long and
deep interest in the subject.
----
Passive Solar is well documented in numerous sources. Check with the Conserva-
tion and Renewable Energy Inquiry and Referral Service (CAREIRS) 1-800/523-2929
----
Note that CAREIRS is defunct, replaced by EREC (Energy Efficiency and
Renewable Energy Clearinghouse). Actually operated by the same folks who
used to run CAREIRS, it also provides the services that NATAS (National
Appropriate Technology Assistance Service) used to provide. The number for
EREC is the same as it was for CAREIRS. In theNorthwest U.S., remember
that you can also call the Energy Ideas Clearinghouse with all your
commercial/industrial energy information questions. (800) 972-3568. Both
services have free bulletin board services as well. E-mail me for details..
----
> 2. larger than average south-facing glass area (to collect more
>solar energy when the sun is shining) (this is somewhat in conflict
>with point 1)
Yes this may conflict with point 1, but I presume you would use
double glased windows as well as a system of closing the window
off at night to help reduce the heat loss through the windows.
I don't come from a cold climate but I would think using outside
shutters and heavy, inside curtains may do the trick. There may
even be some better ideas that people have used.
----
on the photo-voltaic front, a lot of island folk -do- use them
to charge 12v battery banks. then they buy 12vdc appliances and lighting
fixtures (easy in a boat-oriented culture...)
for the week-enders, it works out pretty well... the batteries hold
enough charge to cover the 2-day usage with a 5-day recovery period.
for the full-timers... they buy generators...
----
I can't speak from experience, but I have done some research into
alternative power sources out of personal interest.
It turns out that solar (photovoltaic) power is very expensive on a
per-watt basis. Here you are talking about kilo-dollars to provide
kilo-watts of power.
If there is any possibility, you should consider construction of a water
wheel (unfortunately only possible near a stream or river) or a wind
generator.
With enough wind or water, a home brew system can power a home for a
couple of hundred dollars (or at most a few thousand). You will of
course need battery backup during the 'dead' times, and that system
will require maintenance.
The following book provides some practical details on some home brew
systems:
Pierson, R.E.. Technician's and experimenter's guide to using sun,
wind, and water power. 1978. 621.3124/P62t 168434F
isbn 0-13-898601-0
----
>The following book provides some practical details on some home brew
>systems:
>Pierson, R.E.. Technician's and experimenter's guide to using sun,
> wind, and water power. 1978. 621.3124/P62t 168434F
> isbn 0-13-898601-0
Also contact The University of Tennessee, Energy Environment and Resources
Center. 615-974-4251. They did extensive experimentation with such things
back in the late 70s and early 80s, including building a number of houses.
I think they're still at it.
----
A lot of factors are involved in going off the grid.
As far as overcast in Northwest, etc. there is a fine
example of a fellow in Coos Bay Oregon, a very overcast
place, who built a very simple solar collection panel
on this roof and heated his house the entire winter, after
a series of engineers told him it could never be done
in that Northwester climate.
That was over 20 years ago.
Building inspectors and neighbors often do not like some
of the solar designs if they look "odd" since the former
can't find it in their rules book and the latter are
forever worried about their property values.
As for photo-voltaics, I don't have a lot of info
on using them in the Northwest, but the cost which
has been coming down steadily on solar panels, is
a big factor...for instance covering a normal size
house roof in solar panels used to cost 10,000
dollars or more...
Personally I like the idea of putting the family
dog in a large rotating drum attached to a
generator but I've always been a little
strange.
cheers
----
>I'd like to talk with people who have designed and lived in solar-powered
>houses (Photovoltaics for electricity, passive design for heating) in
>sun-poor areas.
OK. Altho I'm not exactly one of those people. Where I live, near
Philadelphia, we get about 1000 Btu's/square foot per day of sun, on
the average, on a south facing wall in December and January. You get
about 500 in Dec and 435 (ouch) in January, altho the average
temperature where you live is a bit higher, about 42 F vs 34 F.
Nov and Feb are also about 700 Btu's/ft^2/day where you are, which is
about 30% less than here, with average temps of about 45 F. The rest
of the months look comparable or better than here, as far as amounts
of sun go. I'm getting these numbers from page 180 of a nice book
_From the Walls In_, by Charles Wing (Little Brown, 1979, now out of
print, but worth ILLing if you can.)
I live in a stone farmhouse built in 1820, with trombe walls on two
sides and foam on the outside of the other two walls. It has a
sunporch with a fan with a differential thermostat, to collect hot air
>from the porch when it's hotter than the house, and a 1984 Dodge Omni
automobile radiator with its electric fan, in the living room floor,
with well water running thru it to cool the house when the weather is
hot. The house still uses about 300 gallons of oil/winter for heat,
and I don't have solar hot water yet. I'd like to fix that.
>Obvious ways to deal with this reduced sunshine level are:
> 1. super-insulation (to keep as much of the solar heating in the
>house as we can)
Yes...
> 2. larger than average south-facing glass area (to collect more
>solar energy when the sun is shining) (this is somewhat in conflict
>with point 1)
Not if it's sunspace glass, in a low-thermal mass sunspace, with an
insulated wall between the sunspace and the house, and some fans to
blow the warm air into the house during the day, where the heat can be
stored in the mass of the house...
Or you might use a low-concentrating collector like the one described in
problem 33 of the appended opus, to effectively make your sun 2X
brighter, as it is here. It seems to me that a 2X concentrator would
work pretty well even under cloudy or hazy conditions. The reflective
part might be built of foil-faced foam insulation, spray painted with
clear urethane on the shiny side to keep it shiny, and the water
collector part could be a shallow EPDM rubber lined drain down pool,
over a water tank, under a glass floor that you could walk on, which
would not require that the water pump raise the water much...
> 3. bigger than average thermal mass (to store more of the
>available solar energy)
Yes...
> 4. A good, independent backup heat source (eg, woodstove)
Yes.
>Similarly, we can deal with the photovoltaic problems:
I guess... Altho I would put this last, in order of cost/benefit
ratio, ie $ saved/year/$ invested, after space heating and then hot
water heating. Altho I do live near the grid... I'm pretty impressed with
Honda's tiny generators, BTW. I was listening to a 600 watt model a
while ago. Very quiet. Maybe you can use one of these for cogeneration,
to provide heat for the house as well as charging batteries. Trace inverters
seem to have a good reputation. I would get two of them, for reliability,
and forget about 12 V wiring and appliances. Or maybe buy an 8 Kw diesel
(water cooled, and a safer fuel to store) generator and supply your neighbors
with electricity too... Mother Earth News has an ad from a guy in CA
who sells 8 Kw Chinese diesels for about $3K, as I recall.
>I'm curious what people have learned in this kind of situation. I'm
>particularly interested in the tradeoffs used -- for instance, did you
>find that super-insulation was more effective and efficient than more
>thermal mass? What would you have done differently, now that you've
>built the house?
I have learned a few things. Trombe walls are not as efficient as
low-mass sunspaces or hot air collectors. The heat leaks out of the
uninsulated wall at night, thru the glass. At the moment, I'm
installing brown-painted fiberglass insulation, fuzzy side out, between
my stone walls and the glazing, to make it more of a hot air heating system,
and I plan to let the warm air come into the house when the sun is
shining and charge up the heat battery of the stone walls from the
inside. And of course I tested the house with a blower when I moved in
and tried to seal up all the air leaks...
Also, heat is better stored in an unpressurized water tank than in masonry,
for several reasons. Masonry stores about 22 Btu/ft^3/degree F, and water
stores about 62. And it is easier to get the heat into and out of water. The
thermal resistance is less, and it can be pumped around. And heated
with that diesel generator... And a tank usually has a lower surface
to volume ratio than a wall, so a given quantity of insulation is more
effective. And most importantly, perhaps, you don't have to live inside a
water thermal store (unlike a typical passive solar house) so the heat battery
can be charged up to a higher max temp, say 130 degrees, vs 80 degrees, which
extends the time it can heat the house without sun, vs a masonry heat store...
>We're planning on building an off-the-grid house on one of the San
>Juan Islands (in Northwest Washington State, almost within spitting
>distance of Victoria, BC.) Power from a utility is not available on
>some of the smaller islands.
Hey, I was there in March, visiting an SO in Bellingham :-) We
took the ferry over to Victoria, and I remember looking at the San
Juan Islands, and thinking how different the climate was there than in
Puerto Rico, where I will be in December...
>Information on how to beat the brain-damaged Washington State Energy
>Code (which sees windows as energy losing devices only) would also be
>appreciated.
Give 'em mathematics, with predicted performance figures for backup heat
required, with a small computer simulation (in BASIC, say) of your proposed
house, using a $100 floppy disk with the last 20 year's worth of solar
weather (daily hours of sun, min and max temps for Nov-->Feb) and invite
their experts to disagree, if they wish, with their own simulations, or
to suggest changes in your assumptions or models...
>Thanks in advance,
You are welcome. Please let me know if I can help further.
----
I'm not an expert on this subject but I did dabble in the solar industry a few
years ago. I sold solar water heaters in the Toronto area.
Anyway... I would suggest you contact Melinda or Ezra Auerbach of Energy
Alternatives. They live and work on Lasqueti Island in B.C. and are completely
off grid. They specialize in the "alternative lifestyle" that you are talking
about.
They can be reached at 604-333-8898 or by mail at Morewater Road, Lasqueti
Island, B.C., Canada, V0R 2J0. I don't know if they are set up for E-mail.
----
Caveats: I've not done it.
I would suggest that the net heat gain from windows in that cloudy a
climate isn't a viable proposition. On the days it is sunny, it's
probably warm enough that you don't particularly need heat.
Suggest that you go the super-insulation, and heat with wood, and just
do what you can by putting most of your windows on the s. side.
For PV, that's a lot tougher. Suggest that you get a small panel, hook
it up, and meter it to find out realisitically how much power you are
going to get. I'd think in the islands that wind would be a cheaper
alternative.
----
Just thought I'd put in my "inexperienced" 2 cents and ask to post back any
interesting thinks you might find out in this matter.
>I'd like to talk with people who have designed and lived in solar-powered
houses (Photovoltaics for electricity, passive design for heating) in
sun-poor areas.
>From everything I've seen passive solar in the only way to go for
heating/cooling and actually works very well.
A low tech generator may be the best thing for electricity if you can get
propane. Someone may even make a gas fired heating system (for water and
air) does has a generator.
>Here in the Seattle area we often have to deal with a low stratus
overcast for many weeks during fall, winter, and spring. Obvious ways
to deal with this reduced sunshine level are:
1. super-insulation (to keep as much of the solar heating in the
house as we can)
2. larger than average south-facing glass area (to collect more
solar energy when the sun is shining) (this is somewhat in conflict
with point 1)
3. bigger than average thermal mass (to store more of the
available solar energy)
4. A good, independent backup heat source (eg, woodstove)
all good ideas. also consider an air exchanges if things are really air
tight.
>Similarly, we can deal with the photovoltaic problems:
1. a bigger PV array
2. more battery storage
3. more efficient appliances, lights, and inverters
4. a good backup generator or complementary power source (eg,
wind turbine), or, dare I say it, grid power
3 goes without saying, if you can get on the grid at a reasonable $$ (what
are the cost in the islands? -- I would be interested to know) why not --
just be ready to deal with outages (I assume that's a problem?) and the
generator should be just fine (be sure to fire it up occasionally).
>I'm curious what people have learned in this kind of situation. I'm
particularly interested in the tradeoffs used -- for instance, did you
find that super-insulation was more effective and efficient than more
thermal mass? What would you have done differently, now that you've
built the house?
no experience here...
>We're planning on building an off-the-grid house on one of the San
Juan Islands (in Northwest Washington State, almost within spitting
distance of Victoria, BC.) Power from a utility is not available on
some of the smaller islands.
>Information on how to beat the brain-damaged Washington State Energy
Code (which sees windows as energy losing devices only) would also be
appreciated.
Add windows later (unbeknownst to them). Also, if you put thermal shutters
on them will they let you use more? There are automatic systems, and a plus
during storms.
>Thanks in advance,
John
And of course have a computer control everything and use it to gather stats
and ration (warn you of doing stupid things) power reserves if things get
nasty.
----
John,
I read your posting about solar power for a house in the San Juan
islands and thought that your prospects may not be as bad as you paint.
I've spent a lot of time on North Pender Island across the border and my
parents live on Gabriolla. That area has much better weather than either
Vancouver or Seattle so your solar plans may be less of a challenge than you
think.
good luck!
----
I think Seattle and Binghamton, NY run neck and neck on
lack of sunshine. I read a lot of solar stuff, though.
You list of ideas is good with a few comments:
Windows need insulating shutters since they will
only collect passive solar energy 10-30% of the
time in such overcast climates.
Watch out for having so much thermal mass that
it abosorbs so much heat that the mass (and your
rooms) never warm up much at all.
Best of luck to you. There is always some way to
get benefit from solar energy. Work at it and you
will find something.
----
One of the very best places to find info on passive solar design and
siting is the Ecotope Group located right there in Seattle.
Thanks to the climate in the Northwest, I think we've got the world's
experts on passive solar design for cloudy regimes. There are quite a
few folks in Portland who specialize in passive solar house and commercial
building design, and the U of O architecture department has a long and
deep interest in the subject.
----
>I'd like to talk with people who have designed and lived in solar-powered
>houses (Photovoltaics for electricity, passive design for heating) in
>sun-poor areas.
>
>Here in the Seattle area we often have to deal with a low stratus
>overcast for many weeks during fall, winter, and spring. Obvious ways
>to deal with this reduced sunshine level are:
> 1. super-insulation (to keep as much of the solar heating in the
>house as we can)
> 2. larger than average south-facing glass area (to collect more
>solar energy when the sun is shining) (this is somewhat in conflict
>with point 1)
Yes this may conflict with point 1, but I presume you would use
double glased windows as well as a system of closing the window
off at night to help reduce the heat loss through the windows.
I don't come from a cold climate but I would think using outside
shutters and heavy, inside curtains may do the trick. There may
even be some better ideas that people have used.
----
on the photo-voltaic front, a lot of island folk -do- use them
to charge 12v battery banks. then they buy 12vdc appliances and lighting
fixtures (easy in a boat-oriented culture...)
for the week-enders, it works out pretty well... the batteries hold
enough charge to cover the 2-day usage with a 5-day recovery period.
for the full-timers... they buy generators...
----
I don't have the magazine here at work, but the Real Goods company
is holding open houses all around the country about now at the
solar homes of volunteers. I think their home office is in Ukiah,
California. They could supply details of any in your area.
I have heard there are several solar homes on either Blakley or
Cypress Islands, or whichever one has no submarine cable for power.
You might just go there and knock on doors.
>
>Information on how to beat the brain-damaged Washington State Energy
>Code (which sees windows as energy losing devices only) would also be
>appreciated.
>
You might be stuck with talking to an $architect$ on this.
We have a solar vacation home that I'm in the process of wiring.
Planning on mostly flourescent lighting, and of a focused task
lighting philosophy rather than area lighting. For cases where we
stay for long periods we can fall back on kerosene lamps which we
used since the cabin was built. Fallback alternatives such as
kerosene lights and wood heat may make more sense than oversized
panels and batteries; it's hard to size for the 100-year record of
cloudy days, so don't try. We get all the hot water we want from
a coil in the cookstove. Solar hot water works well too but you might
consider this. Buck's Stove Palace in Portland is the best source
of wood cookstove expertise on the west coast, if you're interested.
He sells Elmira/Heartland stoves, but not Waterford (which I have).
The big difference from otehr dealers is he deals in used refurbished
stoves and spare parts. Good luck with your project. I've sailed
in the San Juans in March and the western islands at least are
often sunnier than Seattle due to the Vancouver Island rain shadow.
end part I
--
John Allred (jallred@spdg.com)
Stratos Product Development Group, Seattle, WA
I, for one, _liked_ gridlock.