Newbie building a house...?s

Discussion in 'Alternative Energy' started by RipVanArkie, Jan 10, 2007.

  1. RipVanArkie

    RipVanArkie The Rusty Ewe

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    Hello everyone, new to the group. I am planning to build in May2008 and am trying to work out the finer details of my plan. The home is a hybrid constructed of SIPs and timber frame. I plan to use an in floor heating system and as much DC powered lighting/appliances as possible (only what I need not everything on the market). All ceilings are cathedral exc. bathrooms. Sq footage including lofts is 2400 on a 32x64' framed foundation.

    Now for the questions...

    Any members in Arkansas using solar power? SIPs? floor heat?

    I'm trying to decide on solar panels and a heating design.

    Thanks in advance for all your help and ideas!

    Steve in AR

    Oh yeah, I raise Barbados sheep a few chickens and a large garden.
     
  2. MELOC

    MELOC Master Of My Domain

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    check out the solar shed idea gary posted about. i really like that one.
     

  3. RipVanArkie

    RipVanArkie The Rusty Ewe

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    I haven't been able to find that, can you post a link to the thread?

    Thanks,
     
  4. MELOC

    MELOC Master Of My Domain

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  5. RipVanArkie

    RipVanArkie The Rusty Ewe

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    I like that and it should work, but we don't use enough hot water that the waste would benefit us. I plan to use an outside boiler (wood-burning) to generate hot water for the house as well as the radiant heat system. I've been thinking of using solar collectors at each sun-facing window to bring in more heat that way.

    The house should not really need that much heat. The walls have an R24 and roof an R48 value. We only see a couple weeks with temps in the 0-20 degree range in the winter.
     
  6. Pete

    Pete Solar Powered Aussie

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    I didn't realise it got as cold as that in Arkansas. I've been running on four panels in a passive-solar home for the last twenty years, with cathedral cielings, 50x15 feet,but verandahs and a deck double that living space. Built on a base of 22 poles. Being in Australia it faces North, of course :)
    Good luck with your homebuilding.
     
  7. SolarGary

    SolarGary Well-Known Member

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    Hi,

    Windows are already good solar collectors -- they collect just as well as commercial solar collectors. So, there is really no benefit to putting a solar collector inside of a window. The place where windows suffer is that they lose a lot of heat at night. So, insulate them during the night. But, maybe you meant adding the solar collectors that sit just outside the window?

    There are quite a few simple solar heating schemes here:
    http://www.builditsolar.com/Projects/SpaceHeating/Space_Heating.htm

    and attached sunspaces can be good for solar heating while also adding some extra space and growing plants:
    http://www.builditsolar.com/Projects/Sunspace/sunspaces.htm



    Gary
     
  8. Runners

    Runners A real Quack!

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    Near Callands, Virginia
    I make a habit of DRAWING everything out to the smallest detail in VISIO (sort of like Auto-Cad). It saves me a ton of material, and I can lay it all out, print it, post it where my wife and kids can look and provide input.

    Heck, post your plans here, and maybe we can add some ideas to save costs and share some legitimate concerns.

    One of the common "problems" I hear of with passive systems is what happens when the panels work TOO GOOD - as in the kind of 'winter' we've been having. Maybe the roof overhang is just right for summer/winter, trees are in the right place & type to block summer sun, but let in winter sun... and then we got these 60 degree days in Jan., and the solar gain goes through the roof - you come home to a SAUNA, the dog has heat stroke, the cat is in REAL heat (aren't they always?), and the potted plants have boiled out the last bit of water!

    The same goes for wind or micro hydro - "What do you do with it, when there's TOO much?!"

    Will the glass collectors crack? My brother lost 2 really big picture windows on a home-built solar collector - they overheated one morning... all but a shaded corner and cracked.

    ----------

    As far as DC power. Unless you're using LEDs, or some super-duper efficient lighting source, forget running 12vdc around the house. Some local codes make it illegal, difficult or the insurance company won't allow it. The little money you seem to be saving with 12vdc is lost in COSTLY and inefficient appliances, large wire sizes, switch & control costs - just for starters. Common, everyday kitchen appliances (blender, toaster, sauce pan, etc., even the stuff bought from a truck stop), use a TON of amperage and produce poor results.

    ---------

    Back to Solar....
    Before R-11 was "banned", I was kicking around the idea of a gravity type Solar collector, coupled to a radiator and solar electric fan. R-11 boils in the mid 70s degrees atmospheric, which could be adjusted upwards as heat would bring about increased pressure, thereby raising the boiling temperature. It's also a good carrier of HEAT. The collector would be below the radiator, so the freon would boil/vaporize up the pipe to the radiator, where the solar powered fan would blow air over the coil, reducing the temp, condensing the vapor and it runs back into the bottom of the collector. (2 pipe system).

    My father-in-law and I toyed with the idea (he's a steam fitter), and he suggested other refrigerant possiblities, some with higher and lower boiling points. The main reason we didn't like Glycol is because it doesn't stand up to cycling like real refrigerants - and has to be replaced. One freeze up and your collector is finished! Then there's the corrosive consideration (I'm a licensed LP/HP stationary engineer) - even hot water/glycol systems GROW stuff and and quickly eat away boilers and piping if not properly treated, maintained and tested regularly. Heat does not kill iron bacteria, chemicals only inhibit it... for awhile.

    I would want an idiot proof, self regulating, ultra low maintenance system that wouldn't explode, burn down the house and could be mixed with auxillary types of heating sources to avoid duplicate heat distribution systems. And of course, my insurance company hates anything that doesn't say RHEEM, BRYANT or DAVE what's-his-face on the side. ....I also found out some building inspectors don't like non-standard stuff. What good is a house if you can't get occupancy or insurance?

    Post some plans - I bet there's plenty of folks here that would have useful input. And, no idea is too stupid to talk about - heck I've some so close to killing myself with some of these projects, my mother wanted me to marry a nurse, in case I was maimed instead of killed!
     
  9. RipVanArkie

    RipVanArkie The Rusty Ewe

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    Thanks for your input guys!

    The solar collectors at the windows are outside the window. They have a damper that is controlled by a thermostat. They are mounted at the bottom of the window, when the temp reaches a certain level the damper opens releasing the hot air into the room through the window. Overheating the house might still be a concern.

    I have been using Punch! Super Home Suite to design the house and we are building a scale model as well 1/12th scale as a family project. The wife and kids are all able to see the plans in 3D with a walkthrough and arial view. The kids love changing up the furniture in their rooms and changing the color on the one wall in each room that will be painted.
    [​IMG]

    Please keep the ideas coming!
     
  10. SolarGary

    SolarGary Well-Known Member

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    Hi,

    "The solar collectors at the windows are outside the window. They have a damper that is controlled by a thermostat. They are mounted at the bottom of the window, when the temp reaches a certain level the damper opens releasing the hot air into the room through the window. Overheating the house might still be a concern."

    For solar collectors, as long as you have an overhang over the top of the collector to prevent overheating in the summer I think you will be fine.
    The occasional warm day in the fall can be taken care of by more ventilation. I've heard from a lot of people who wished they had more collector area, and very few who wish they had less.
    There is a good tool for designing the overhangs here:
    http://www.builditsolar.com/References/SunChartRS.htm

    The HEED program that is listed on the same page will let you see how your home performs. Its a full blown hour by hour simulation that uses your local weather. Its also very easy to use -- you can model a home in half an hour. It provides tons of 3D graphs that show heating and cooling needs, times temperature exceeds a certain value, ... All FOR FREE thanks to the California utility users who paid for its development.

    This is just my 2 cents, but the window collectors are not what I would use for a new design home. I would rather try to integrate the collector area with the design. This might be more glazed area on the south (with overhangs, and with thermal shades at night). Or active collectors on the south wall.
    For space heating, vertical collectors (or windows) have the advantage that they do well in the winter when the sun is low, but have much less tendency to overheat in the summer when the sun is high. The summer radiation on a vertical surface even without any shading is well under half the radiation on a collector tilted at your local latitude.

    It would be possible to build a collector of this type in part of your south wall for very little cost increase over a standard wall. It has no overheating potential because you can just shut off the vents when you don't want the heat.
    http://www.builditsolar.com/Projects/SpaceHeating/solar_barn_project.htm



    Gary
     
  11. RipVanArkie

    RipVanArkie The Rusty Ewe

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    That looks very do-able. The main living area of the house is 32x32 with a 10' outside wall. This would be the south facing wall.

    I get excited every time I can add a new idea to my plan, especially if it will decrease the day to day living expenses.
     
  12. MELOC

    MELOC Master Of My Domain

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    screw the insurance companies as far as i am concerned. chances are they will do the same to you when you need them most.

    there are lots of ways to dump heat and energy if you need to. a coil and fan vented to the outside would cool a collector. i also think the use of regulated shade screens may help.

    the freezing concern and glycol concerns are real enough. i know an HVAC installer who installs outdoor furnaces and uses glycol and i think it is a bad idea. you could probably design a system that drains out when the temps get too low.

    i have never heard of zoning issues with 12 vdc, but i believe it. i really don't see how it is any more dangerous than ac. windmills and hydro can be shunted directly to ground if need be.