New construction-self sufficiency, green power, redundancy, and lots of other questions...

[Badfish740]

The wife and I are currently working toward our dream of buying 10-15 acres and either mostly demolishing an old house and starting anew or building from scratch. I'm not looking to build some sort of compound, but we want to be as self sufficient as possible for a variety of reasons. First, this would be our second and last home, so we fully intend to reap the full benefits of return on investment in self sufficient power. Next, the places we are looking are in the most rural and isolated parts of New Jersey (stop laughing) where the power grid is old and even if it was new tree crews could never possibly keep up with the amount of trimming it would take to ensure that power lines never came down in the winter time. So between old transformers blowing up because of overheating/overloading in the summer, and downed lines because of ice and snow in the winter, it's nice to have a fall back. Most folks out there have gas powered gensets that they wheel out of the garage and plug stuff into, but I'd like something permanent and with more power output, but of course engine powered gensets are but one option, as I mentioned above, redundancy is a feature I want. I should also add that throughout construction we want to make use of good insulation and other methods of reducing the NEED for energy in the first place. We plan on building a milled log home, which, when properly sealed provides excellent insulating properties, but we also plan to incorporate other technologies/techniques as well (white roof, lots of attic insulation, quality windows, etc...)

The way I see it there are a bunch of options out there that can satisfy the two basic home energy needs: electricity and hot water:

Evacuated solar tubes - Hot water
Photovoltaic panels - Electricity
Wood gasification boiler - Hot water
Internal combustion engine powered generator - Electricity

I thought briefly about small scale hydroelectric as it would be possible to buy property where we're looking that may or may not have a stream with enough head to support it, but water use regulations and other challenges make it a little less attractive. Wind is something else I wouldn't want to get involved with either. Besides, with the above listed systems I would have two and two. My question is this-how do you tie all of this stuff together in such a way that it works seamlessly and can operate completely independent of the grid if needed? Let's start with hot water since that at least seems easier to me. Evacuated solar tubes are pretty simple devices that can generate very hot water even in cold weather, but of course are subject to the availability of sun. Does anyone here have evacuated solar tied in with a wood boiler system? If so how did you do it? Anyone have ideas on how TO do it? Either way I'm thinking that there would have to be some sort of computer controlled devices involved in order to regulate where hot water was going and how hot it was allowed to get. That's where I get totally lost...

Now for electricity. I realized a moment of frustration when I learned that most grid-tied photovoltaic systems do not work when the power goes out, presumably because systems that could adapt to power outages are much more expensive. The idea of being tied to the grid is attractive to me mainly because of the idea of selling power back to the company, plus my main fear would be if generator suffered a catastrophic failure that would result in me waiting for parts/etc...and in the meantime only having photovoltaics as a power source. So here is the question-if I were to install a photovoltaic system large enough to power the entire house plus a large permanent generator, how could they be installed in such a way that would allow everything to coexist? Would I need large banks of batteries? If so, what kind of battery life would I be looking at? Replacement every five years? Ten years? I realize that this is a lot to answer, but what I'm hoping will happen is that a bunch of folks interested in the same concepts get together and exchange some ideas and help each other better understand how this stuff can work.

 

[d.n.f.]

Hydro power runs 24/7 (unless the source freezes). No batteries needed. I was about to install a system but then we moved... Batteries are a huge cost and they don't last forever.
PV panels. Lots of sites will tell you how much power you will generate depending on lat/long and also cloud cover. Without rebates solar is expensive and not that efficient for electrical. You will need to modify your lifestyle if you are truly off-grid.
Solar is dirt cheap for hot water.
Unless you are in one of those windy zones it seems wind power is more a novelty power source.


There are a lot of people out there that work on off the grid power stuff. They know how to tie all these things in together. Finding a non-quacky one is another matter. Good references and all.

 

[Badfish740]

There are a lot of people out there that work on off the grid power stuff. They know how to tie all these things in together. Finding a non-quacky one is another matter. Good references and all.

Yeah-the non-quacky part is a tough one. This guy seems to have his stuff together though:

http://www.f1-rocketboy.com/lister.html

His application is generator only, but after a bit more reading the way I understand it is that grid tied systems can be used in conjunction with generators through the use of a simple transfer switch. Basically under a normal situation the grid is tied to the home as the switch has two positions-grid feed and generator feed. In this configuration the solar panels operate and feed any excess power back to the grid. When the power goes out, the switch is turned to generator feed allowing the power to flow from the generator into the house. What I don't fully understand at this point is that let's say the power goes out on a bright sunny day. The generator is now feeding the house so no problem there, but what about the solar panels? Where does that power go?

 

[Jags]

steam engine turning a generator. Electric and hot water all in one.

Good luck on your quest. I would like to do this at a later time in my life as well.

 

[Badfish740]

steam engine turning a generator. Electric and hot water all in one.

Good luck on your quest. I would like to do this at a later time in my life as well.

Hehe...good one. I'll stick with a Lister diesel like the one in the above link. My Powerstroke runs exceedingly well on vegetable oil and Listers do too, the best part being that they are very tolerant of dirty, wet fuel. Not that I would intentionally burn dirty or wet vegetable oil in it, but its good to know that I could if needed.

 

[Marty]

Get one of these:

http://www.youtube.com/watch?v=xEdQRVQtffw&feature=related

:D

 

[Badfish740]

Get one of these:

http://www.youtube.com/watch?v=xEdQRVQtffw&feature=related

Ha! I actually know Mike fairly well, but alas his stuff is out of my price range

 

[Marty]

Get one of these:

http://www.youtube.com/watch?v=xEdQRVQtffw&feature=related

Ha! I actually know Mike fairly well, but alas his stuff is out of my price range

I noticed he was in your state.

You've got to have money to burn to be that thrifty alright.

 

[kobudo]

Our vacation home is in a remote location so we need to provide our power off grid by necessity.

We had 6 solar (pv) panels installed along with a "tracker". In addition, we have 4 large sealed 12V batteries that are expected to last +/- 10 years. Some items run directly off the batteries (lights, ceiling fans) some items are plugged in and the power goes from the batteries through the inverter. In additon, we have a generator for use as a backup/supplement to the solar power. The generator runs on propane as does the fridge, stove, instant on demand water heater, and 4 small direct vent propane heaters that we run when we are not there. (we heat with wood when we are there).

The solar panel/battery situation has provided all the power we need. We do run the generator montly just to make sure it is in order. In order to to limit our power consumption we light primarily with LEDs along with some florsnts. Since this is a vacation home we do not have a dishwasher, washer or dryer. We do have toaster, microwave and other small appliances. We do use a vacuum, shop vac etc. The biggest power draws come from the well pump, septic pump(mound system) and heat tape on water lines in the winter.

We consume about 1000 propane per year. I would say 90% of this is for the heaters that we run when we are not there. (It gets very cold in the winter)

If you use a lot more power it would make sense to increase your battery bank from 4 to maybe 8 or 12. You could also increase your solar panels to 8.

This is not a cheap solution and it is much cheaper to use power off the grid. But if you choose to do it out of necessity or to get off the grid it is certainly something that can be accomplished.

 

[kenny chaos]

An old lister for me please.
They're based on the original "Diesel"
design and will run on any oil, even, used.
I read about one that ran 24/7 for 125 years
without stopping.
For some strange reason, the government
recently outlawed the import of any new ones.

 

[jebatty]

We plan on building a milled log home, which, when properly sealed provides excellent insulating properties,

Milled logs look great, but am I correct in understanding the R-value is about 1 per inch? If so, not really that good. Also, maintenance cost is high on logs of any kind, cracks, sealing, insects, weathering, staining (unless you don't mind gray), and more.

Energy self-sufficiency is a worthy goal. To make it work, IMO, a person or family really has to reduce power consumption way below what we all are used to. And while doing that, an equally worthy goal is simply to reduce all consumption to necessities -- greatly simplifies life.

 

[Hakusan]

You should look into a hybrid power system--solar/wind. It is much more efficient than either by themselves. Hydro is great if you have the head and flow. You can be grid intertied and still have a backup battery system--it is not an either/or choice. You may also want to do research on masonry heaters. They can be one of the most efficient heating systems.

 

[Badfish740]

Milled logs look great, but am I correct in understanding the R-value is about 1 per inch? If so, not really that good. Also, maintenance cost is high on logs of any kind, cracks, sealing, insects, weathering, staining (unless you don't mind gray), and more.

I guess excellent was a strong word. I had read that the R-value of dry logs was actually 1.5 per inch-I researched this and found claims of anywhere from 1 to 1.5 depending on moisture content, species, etc... I didn't realize that the R-value of a 6" thick fiberglass insulated stick framed wall was much higher. In any event, logs do provide thermal mass which should help with heating and cooling. I grew up in a milled log cabin and can attest to the thermal mass part. My dad finally finished the crack sealing about 2 years after the house was finished-he applied a sealer (not sure what kind) once the crack sealing was finished and the logs are just starting to look as though they need sealing again-that was 22 years ago. I could deal with having to re-seal every quarter century or so Insects were never a problem, but there could be a whole host of reasons for that from species of wood to the region where the home was built. I will admit that the choice of logs is more for looks than energy efficiency anyway.

Energy self-sufficiency is a worthy goal. To make it work, IMO, a person or family really has to reduce power consumption way below what we all are used to. And while doing that, an equally worthy goal is simply to reduce all consumption to necessities -- greatly simplifies life.

This is something we'll have to work on. Right now it's just the two of us and we work a lot, so our energy usage is not all that much, but by the time we get to the point of building our homestead there will be a little one or two. This is where "do as I do" will come in. I am already a "light Nazi," so the kids should get the point about energy usage from their old man. Does anyone know a place on the web where you can get rough ideas of how to calculate the electrical load of a house?

You should look into a hybrid power system--solar/wind. It is much more efficient than either by themselves. Hydro is great if you have the head and flow. You can be grid intertied and still have a backup battery system--it is not an either/or choice. You may also want to do research on masonry heaters. They can be one of the most efficient heating systems.

Hybrid is sort of what I'm going for in the sense that I'll be utilizing solar and a generator. I didn't realize that batteries were also utilized on grid tied systems though-I'll have to look into that more. Batteries seem like a hassle to me though-replacement, maintenance, etc...

 

[DBoon]

You should check out Home Power magazine - subscribe and buy a year or two of back issues. This will answer a lot of your questions.

In general, evacuated tube solar DHW collectors only make sense if you need smaller quantities of very hot water (~160-180 degrees) or live in a fairly cold and cloudy climate. NJ doesn't qualify, so standard flat plate solar collectors make the most sense. About a year ago, Home Power had a description and ratings of all available DHW collectors and an explanation of what all the ratings meant.

Any type and style of home can be made very energy efficient. If there is already a structure on site that you can or want to re-use, that is as green as it gets. Even if you strip it down to bare studs and add an addition, it's still better than building new. There are lots of very informative articles on green and efficient building including insulation systems in Fine Homebuilding magazine. The publisher, Taunton Press, also publishes many books on green and efficient building, and they are written so that a layperson can understand them. In general, outside walls in buildings should be double insulated with elimination of thermal breaks. Using a foam insulation (there are soy-based green types available) can provide R-5 per inch and if you have an effective 6" thick wall, then you are getting R-30 with no air infiltration (requiring auxiliary air heat exchangers). Also, thick about how windows can be chosen to optimize solar gain and thermal insulation.

I agree with Jebatty - think about how to conserve first. Conservation costs less per watt than alternative energy systems.

 

[JustWood]

Stick built bank home. Spray foam insulation.Metal roof and siding. Tight and energy efficient.
South facing windows and good exposure, solar shades, heat sink, etc.
500 gallon gravity feed water storage.
Rain water roof collected sistern for gardening purposes.
Natural gas genset and battery bank for power fed by gas well on property.
This is my goal.
I have a friend that is set up this way except on a diesel genset. He runs the gen for 3 hours every 3 days to charge up the bank. While the gen is running he and his wife do laundry, vaccum, wash dishes, pump holding tank full of water, etc . When powering off the bank they use minimal electric mostly for lights. Has a small wood fired hot water heater and also solar water heat.

 

[mainemac]

First of all good luck in your endeavor it sounds exciting.

Construction
I like all of the ideas thrown out in terms of energy efficiency.
HayBales have fantastic R values, my neighbor built a house with one in PA and it works great.

Heating Cooling
I am wondering why you or the other respondents did not mention geo-thermal.
My brother has had one for 20+ years and it cools his house in the summer and warms it in winter.
He has a wood stove for extra heat in Dec Jan Feb.
In NJ I would think it gets pretty hot in the summer so having the cooling option is great.
Good luck !

 

[d.n.f.]

Bales put on the long side of the bale is supposedly R70. On the normal wide side (most homes) it is r45.
I lived in a strawbale house for two years.
It was the quietest, coolest, warmest and most comfortable home I ever lived in.
When it was 100F outside it never got hotter than mid 70s on the inside (windows closed during day), with no air con.
Cheaper to build, cheaper to finish (no drywall). Everyone who walked in said that the house just felt cozy. Must be the stucco and the thick window wells.

I miss that house every day.

 

[Wet1]

I an't say I've ever seen a strawbale house before. Sounds interesting. Bugs, rot, and structure aren't an issue?

 

[d.n.f.]

Moisture is the problem. If it gets wet it gets mouldy.

Bugs don't seem to be a problem from what I have read.

They are also very fire resistant. The straw is packed so tight that it hardly burns. There have been straw structures in CA that have been untouched in fires. If the roof goes that is another matter.

There are straw homes on the prairies that are well over 120 years old.

http://www.greenhomebuilding.com/strawbale.htm

My old house is in the New Strawbale Home. I didn't build it though.

 

[mainemac]

I an't say I've ever seen a strawbale house before. Sounds interesting. Bugs, rot, and structure aren't an issue?

As DNF noted there is no oxygen in there ; no bugs no fire no worries
My friend relates that they would put up a pile of hay bales then screw them down very tight, then plaster over them. All the 02 is squeezed out.

Tom

 

[jebatty]

Green, energy conserving, homebuilding is way beyond foam insulation and steel skinned structures, both of which, while energy efficient, consume huge amounts of energy, petroleum and/or coal in their manufacture. Take a look at Greenhomebuilding for some great ideas on the many different types of home construction that might more honestly be called green. Some of these have been around ever since a human desired shelter.

 

[loggie]

I am in New Jersey also and built a log cabin,we went with a handcrafted full scribe 12 to 16" logs of spruce.They say a log wall is around r-1 per inch so if you are going milled I would get the thickest log you can get.My neibor has a 2300 sq foot 6" milled home with High ceilings and he has to burn 2 stoves in the winter to heat it so it does not seem to efficiant as my brother in law has a very simular house a little bigger stick framed 6" walls and heats it well with one stove.As for my house it is also hard to heat as it is a challenge to keep everything sealed up and tight with the setteling we have even after 9 years.
Log homes do better in spring and fall with the thermal mass but I think you give it back in the winter.The biggest problem is all the high ceilings and walls of glass many of us incorperate into our log homes.The tightest homes I have seen have been timber frames with sip panels,they have some high r values and low heat demand.I put a wood boiler in my basement with 1250 galons of water and added an extra coil in to connect solar panels which I have not installed yet but it will be tough to make a dent in heating that much water.As for wind power in our area it is marginal unless the site is ideal.