Thursday, August 16, 2012

Cabin Progress / Solar / Storm

Got the first half of the north window installed and dried in. I'll cover the metal frame I constructed with wood later on to make it look more like a window.

The inside which is temporary. I'll be adding the second half which is another two pane glass section later. This window will not be made to open and I want it to be as energy efficient as I can make it (With in reason). You see a one pane window glass only has an insulation factor of R1 and a dual pane window only has an R rating of R2. The walls will be R-19 or more depending on what else I do to raise that rating. I'm going to be adding another dual pain window to this to raise the R rating to R4 which will be considerably more energy efficient. I'll have two windows like this and the other one will be facing east toward 9 Points Mesa. A third window will be on the south side which will be the little bathroom type window that Bigfoot brought me. It will be the only window that will open, but it will only have an R rating of R2 so I'll have to figure out a way to improve that. I plan to add some type ventilation system that won't effect the overall R rating when it isn't being used, but at some times of the year it will hopefully keep the cabin at a reasonably comfortable temperature and will likely be used during the summer nights. I don't plan to put a window on the west side to keep the hot afternoon/evening sun from heating up the cabin, but I may add a small port window later. There really isn't much of a view to the west.

This is what I'm working with. The dual pane sections that came out of the two windows I traded Frann a new bathroom window for. The two windows I got from her were starting to fall apart because the sun had gotten to the vinyl that was holding the pains in the frames. Those windows were actually considerably larger than I wanted also so since they were coming apart I decided to build the windows I'm working on now.

This is the old windows the panes are coming out of. There will be a total of four (Just right to make two windows like I'm building.) I'd hoped to get the second window (outside section) framed in to the east side of the cabin today, but the high temp, lack of even a breeze at times and higher than normal humidity made me say to heck with that. Maybe tomorrow morning?

I did an accurate count of all the solar panels this afternoon after the storm (see next) and it turns out that I still am below 1500 watts. It is 1425 watts instead. This should still run the little AC unit during the day no sweat but hopefully my nephew will keep coming up with panels for me. I'd like to at least have 1500 watts and sure wouldn't gripe about 2000. ;) Of course at some point I'm going to have to come up with more batteries to use all the solar and maybe be able to run the AC at night.

We had another doozy of a wind and sand storm this afternoon. As usual stuff was blowing everywhere. I had a five gallon bucket of soda cans full of crushed soda cans I'd picked up and of course the wind blew it away and scattered all the cans out again so I get to pick them up all over again. Grrr!

One good thing about the storm is it brought in a lot cooler air and a few sprinkles along with clouds which also helped cool things down. The storm didn't last long, but it dropped the temperature from about 106 to 80 degrees real quick. Should be a real good night for sleeping. :)

You might have caught the comment about picking up soda cans above and wondered why I didn't say soda and beer cans. Well that's because I quit drinking any alcoholic drinks a good while back. That's good in one way, but I find I'm drinking about as many sodas as I used to drink beers and that can't be good for my kidneys! At least I am drinking more water. I also started taking vitamins and for some reason my eyes are getting better. Most of the time I don't have to wear my readers while on the computer. Real small letters still get me though. Hopefully smoking will be the next thing I quit.

Now to my friend and neighbors who come to my parties don't worry. There will probably still be parties, but I figure I will only make the acceptation of drinking at my own parties. I don't want to be a dull boy all the time. ;)

Oh BTW I also got the north side of the cabin sealed up and ready to finish painting it. I still lack finishing the west and south sides and of course I hope to start adding on the bathroom on the back before long to.


  1. Good for you on quiting alcoholic beverages. I quit over 20 years ago and glad I did. Also quit smoking about ten or fifteen years ago. My father-in-law always said to "be careful of the guy with no apparent vices". A lot of truth in that.

  2. DD, I thought I'd cut down on smoking when I quit drinking, but not so. I guess I'll have to go cold turkey on that to. Now that is going to be tough!

  3. Your cabin is looking good! Glad you got the window installed. Hope you get to move in this winter and be cozy.

    I caught the soda can comment but thought perhaps now that what you put on Facebook and/or perhaps Blogs can be used against a person, you decided to omit beer cans :)

    Wish you had given up cigarretes before beer but you are in the right track!

    Think I will die drinking has to have at least one vice :D

  4. I hope so to MsB.

    I figured I had to quit one or the other first, but I took antibiotic for a couple of weeks so had a two week jump on quitting drinking.

  5. David - Looking fabulous! For your opening R2 window - have you considered placing bubble wrap on the inside of it. It does improve the insulation, while still allowing the light through. I know bubble wrap isn't a long term solution (unless yo make it a fancy frame) but it should help you through the winter... ?

    Yeah - I also need to quit your last mentioned evil...

    Nice amount of solar you have there - when the garage is finished and the panels are up we're going to end up with 930 watts but we'll also have 6 X 1138Ah 2 volt batteries - that should see us through the nights, and those cloudy days :)

  6. Lookin Good, the progress continues.
    About your wording ‘which is temporary’. When growin up one of retired neighbors favorite term was ‘there is nothing more permanent then temporary.’ I found that to be pretty true if the temporary is still workin there is some much other stuff to do probably also temporary. :)
    Keep plug in at it.

  7. R Value on windows is not the only measure anymore. Glass uses an inverse parameter for insulation value called u value Obviously double and triple pane is better than single pane, primarily because it stops heat conduction (heating of a material on one side which is then conducted by the material to the other side). Argon gas filled window assemblies are beter than air filled. Vinyl window frames are better than aluminum for reducing conduction of heat. Most insulation tries to stop conduction of heat. I believe closed cell or rigid foam does it best and provides real world heat load reductions of 50 to 75% as measured by air conditioner power and sizing requirements. Would you rather have a foam ice chest or a fiberglass one?

    Performance glass has a low-e coating on the inside of the first pane (hot climates use low-e on the outside pane to reflect heat back). Basically low-e glass is similar to a window film but generally better than window film (which you should at minimum use on your homebuilt assemblies). Both low-e glass and window film have parameters to measure it's effectiveness. The key for southern climates: a low Solar Heat Gain Coefficient (SHGC)

    SHGC is the percentage of solar radiation admitted through a window, expressed as a number between 0 and 1. The lower a window's solar heat gain coefficient, the less solar heat it transmits. You can buy glass or film with low Solar Heat Gain (ideal for hot climates) or glass with High Solar Heat Gain (cold climates). Think about those huge glass buildings in El Paso or San Antonio. They are not practical without low-e glass.

  8. Dani, I'm thinking along th lines of two sheets of Lexan fused together like a dual pane window, but have a rubber gasket around it where it can be placed on the inside of that window and removed when I need airflow. that will bring the R value up to 4 or more because Lexan doesn't transfer heat/cold as well as glass does. That and I wouldn't have to worry about it getting broke while leaning up against the wall waiting to be used. Might even put it on hinges so it can just open back against the wall when not in use. I've used bubble wrap quiet a few times and it works well but is hard to see out of.

    Sounds like you'll are ahead of the game on solar.

    OGR&D, I'll finish up the windows, but the reasoning for just getting the outside panes in first is to rain proof. Of course I could just finish one at a time, but while I'm on a roll I what to get all three windows in. I know what you mean though. There's a lot of permanent temporaries around here. ;)

  9. rj, I'm having to use what I have so won't be buying any new glass or windows. I will likely put solar film on the inside and I guess I could put it on the inside of the outside panes and then again on the inside ones to (on the windows I'm making.) The south window won't see much sun until the winter months though. That could be a benefit in helping heat the cabin then if I didn't add any solar film. The only window that will see a lot of sun will be the east window catching the morning sun. That will end around 11:30 AM with the large amount of overhang on the front of the cabin roof.

  10. Glad to see you are making cabin progress. Lookin damn good.!

    Now who am I gonna sip whiskey with at the Legion (or at your place) when we come to the cabin next time? If it's Lee I may end up chokin' him, but hopefully not. Hate to be a bad influence and I do notice I feel alot better and can do more things when I lay down the bottle for a week. But damn, I like the mellow feeling I get after some corn liquor is coursing thru my capillaries.

    I have a couple left over brand new horizontal slider windows from the apt rehab. Heavy vinyl frames, Low-E, glass, with 3/8" dead air space - insulated glass. Big windows, but they operate. 5' wide X 4' tall. With the SHGC factor of .28 so they are pretty high energy savers. Even have screens for them, somewhere in our storage area.

    I know you want small windows, but think of the view of the Christmas Mtns out your south window you could be catching. But that's the one wall that gets alot of afternoon sun in the summer too...unless you built a shade porch on that side too.

    I'm full of opinions...but you know what that's like...everyone has one.right?

    Thanks for the update...keep up the good work my friend.!!

    seeya in a few weeks.


  11. I would only use film on the inside of one pane of glass, eg the outside window. Radiation is the most intense from direct sun exposure, but all hot objects emit heat radiation, so low-e glass and window films can help on any window in southern arid conditions.

  12. BF, blame it on Caren, She told me I needed to quit the last time you'll were here. ;) Na... actually I figure if I'm ever going to get the cabin finished I got to quit. Hopefully smoking will be next.

  13. rj, like I said I'm stuck with what I have because I'm not going to put any big windows in there. At some point I may put 4 security cameras facing each direction where I can display the view in each direction on a 22 inch monitor.

  14. Hi, I'm new to your blog - enjoy it alot. I live off grid in Oklahoma - by myself now. Husband of 41 years died last month. Just wanted to comment on your plans for a/c. I have 8 80 watt solar panels and 8 L1600 batteries. We tried to run a very small air conditioner. Not for long. It's the amps you have to consider, not so much the watts. Also, our inverter won't let the batteries go lower than 11 volts before it shuts down. I know someone with a system 3 times as big as ours and they don't have much luck with a/c either. Not trying to be negative. I really hope it works for you. I admire all the work you've put in your place. I know it's not easy.

    1. Sorry to hear about your loss. I lived in northern Oklahoma for a few years and know that it can get really hot in the summer and very cold in the winter for many months at a time. In between you get tornados and monsoons. Humm, maybe that's why I moved. Anyway, what you need is a DC powered heat pump, not available at Home Depot although I have seen them at Lowes lately. For a 9,000 BTU unit you pay a lot but you get unbelievable performance. A conventional $200 window unit will have a SEER of 10 and a startup amp surge of 75 amps or more. Clearly a solar inverter will often choke even though the running amps are maybe 12 or 15. The heat versions of the cheap units have resistive heat coils, usually limited to 1500 btus (15amps w fan) in 115vac units. Heat pump window units may give 4500 btus heat for the 15amps but fail to heat at 35-40F. A Mitsubishi mini-split will start on far less than 15 amps and run on as low as 7 amps because of a SEER 26, 2.5 times more efficient than a window unit while still cooling great. Heat will exceed 9000 btus all the way down to 5F with the same low power. How? Inverter based DC compressors and fans allow superb speed control. Linear expansion valves regulate freon flow according to speed. Otherwise wasted outside unit heat is better captured in heat mode. Downside? Maybe $2000 instead of a $500 "window unit" heat pump, if you could even find one. Payback, comfort year round on solar capacities, closing in on swamp cooler and fan efficiencies, while very quiet and producing a little condensate for your garden.

    2. This one is selling for $900 and gives 9000 BTU of inverter based cooling and heating. The 19 SEER cooling requires only 643 watts of 115vac.

  15. Anon, sorry to hear about your husband.

    As for as the AC goes it runs fine down by the battery bank so I need to move the battery bank up close to the cabin and use bigger wire to connect it to. There are several people running small ACs like that one off grid around here and don't have much or any more than me and they say theirs does fine. They do have more batteries though, but that shouldn't matter during the day. Nick runs one and he actually has less solar than I have. Those ACs shouldn't pull over 600 watts running so you really don't have enough solar for that if you run anything else with it. Don't know why the person with three times what you have can't run one?

    One thing to keep in mind is if it is real hot and the building is real hot then that will make the AC pull a lot more AMPs / Watts until the building cools down because it runs the head pressure on the compressor way up. Best way to do it would be to turn it on in the morning when the temp is down and the building is a good bit cooler.

  16. BTW we had a pretty good storm last night. High wind and heavy rain at times. I figured I'd find over an inch in the gage this morning, but it was just shy of 1/2 inch. I checked the pond this morning and it is empty. :(

  17. Compressor start-up currents are gigantic. So a hard start kit (big capacitor and relay)helps a little, but a big battery bank helps a lot. The battery bank can supply the huge amp spike that occurs for a second or two. Some would also put a delay between the compressor start and the fan start. Best overall? An inverter based compressor like Mitsubishi has in their mini-splits.

  18. I know rj, I did HVAC for 35 years. ;) I'd bet the start AMPs on that window unit don't come close to the start amps of a car starter and its only using one battery. 420 HA of batteries, adequate wire sizes and a big enough inverter will easily start that unit and the solar feeding the batteries will run it no sweat.

  19. Your blog is quickly becoming my favorite from the area. Thanks for keeping us in the loop.

    I was talking to Ron because we'll be moving into one of those buildings he's selling and we talked a little bit about windows. I asked him about leaving the windows out, and me adding my own upgraded windows later and he said it would make no difference because of the low R values - even with double pane windows (like you've pointed out here). It seems like it would make more of a difference in the winter than in the summer?

    I guess my question is... if you bought one of those buildings, would you do anything with the windows, or just shoot for as few as possible? I know JW covers his up and that makes sense too, but how much does that really help? We're in the early stages of trying to figure out how we'll cool an 18x40 building. We thought about going underground with a quonset hut or something but it seems to be way too much $$ and work - and then I worry about leaks. So basically we're dead set on moving forward with a Derksen building and trying our best to cool it with solar. We have 1k watts now, along with a pretty nice inverter and charge controller. We're hoping we can make it happen!

    Keep up the great work. You really don't know how much inspiration you're giving to this family who is completely in love with the place. I know it's not for everyone, and some call it hell... but it's our hell and we cannot wait to get there full time.

    Chris Miller - One Family's Journey To Finding True Happiness

  20. RJ - I just went back and re-read your posts. Lot's of good info there. Thanks for sharing. I have bookmarked this and i'll probably have to read it another time or ten to wrap my head around it, but I do thank you for taking the time.

    Chris Miller - One Family's Journey To Finding True Happiness

  21. The only way I would live in a Texas desert is with effective cooling and a sustainable water supply. To me effective cooling without utilities would mean small building, sealed on all six sides with spray foam, low current draw 28-30 seer heat pump and probably x2 solar capacity. All available now. A breakthrough or technical repurposing is needed in power storage over lead acid or AGM batteries, although I would do that for now with first class charge controllers to extend the lifespan. I think some sort of mechanical storage might be possible today but is costly now. Have to think out of the (battery)box.

    By sustainable water I mean the old school definition...I would have to be able to sustain it over a year long drought. Either a well or lots of storage and the ability to capture significantly all the water when it came. Here in central Texas some use 40,000 gallon storage when rainwater is all they have. And then we usually get ~33" of rain a year.

    (I would also let the blog users edit..)

  22. rj wrote: "(I would also let the blog users edit..)"

    Edit what?

  23. Edit their own posts so we didn't have to delete.

  24. As far as I know I don't have a choice in that. Take it up with Blogger and good luck with that! If I screw up on a post I have to delete the post and repost it to.