solar power

[vojacek]

anyone have onfo on converting to solar power? we're in texas and electric prices are becoming outrageous!!! in 2000 we were paying .07/kwh, now .13/kwh. besides that, i'm just fed up with the electric company.  

[Bart_Cubbins]

Homepower magazine is a good place to start...

http://www.homepower.com/

They put out six issues a year and you can always download the current issue for free (registration required, but they don't bug you). Besides the current issue, they also have a bunch of articles from past issues available.

Any questions, these are the newsgroups to hit... the first one is actually named for/inspired by the magazine...

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&group=alt.energy.homepower
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&group=alt.solar.photovoltaic
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&group=alt.energy.renewable

Lots of cross-posting between them, and lots of posters with big egos, but also lots of knowledgable people willing to answer questions.

Bart

[Shelley]

Hey Bart, I'd be interested in your opinion as well as John's and Glenn's if they have the inclination.

We've been exploring what's new in the last 30 yrs.  Had an active HW heat thing with a heat exchanger dealie when we had an all ele house in Durango a long time ago.  We've concluded that there isn't much new.  PV has dropped in price somewhat.  Payback will be about 40 yrs.  Useful life on the PV cells is 25.  Hmmm.

New place will use propane and are trying to reduce it's usage.  Plenty of solar mfgs and resellers here.  Been visiting and talking to them.

Here's what they say.  On the grid?  Keep it simple unless you're rich, stupid or both.  PV doesn't pay back, wind turbines won't pay back.  This is from guys who make their living making and selling this stuff.

What do they suggest?  A simple HW pre-heat thing such as John designed for his house....and the simple air collector with a small blower motor and a convection loop.

Since you've obviously been checking this out, I'd be interested to know your conclusions on this subject.  We have no tax credits here and it's about .08/KH

The 40x60 metal shop thing will be the test bed for whatever we choose.  If it works, we'll transfer it to the house.

[glenn kangiser]

Gosh, Bart, let me humble myself for a minute or two here.

Here's my 2 cents.  

If you want to live like you are now there's not much sense in changing to wind and/or solar.

If you hate the electric company, have some extra money, like to play with interesting things, and want to be self sufficient no matter what it takes then maybe it is for you.  Generator backup is a necessity unless you overbuild your system a major amount, as there are times when there is no wind or solar to speak of or just always a bit short.  Too short for too long without doing something about it and you ruin your batteries.

Forget running a swimming pool, electric dryer, electric heat, electric water heater etc.  unless you want to make the system way bigger- these things can be done better with propane anyway.  If propane gets too expensive - build a wood gas generator or methane digester but be prepared to spend quite a bit of time fooling with them.  Good if you have time and want to prove a point.

Cost -
4000 watt sine wave inverter -$4000 (only about 35 amps - most of you currently want 100 to 200 amps)

All lights -change to compact fluorescent-or fluorescent - LED's are bright but fairly narrow focus.

Panels -appx $4.00 per watt - I have good sun - 1320 watts solar - would like more

Wind generator if you have wind - 1000 watt = $2000 plus tower at about $2000 plus install $4000?
I built my own 85' tower and installed it myself.

Batteries - $150 each for L16's -need 8 or more to start.  2/0 cables - made my own with wire and smashed, drilled, soldered copper pipe ends for terminals.

This is enough to run a water pump part time, (gen assist in winter), CF lights, 2 computers, DSL modem and wireless, printer, energy efficient freezer and refrigerator, microwave, occasional use of table saw, compressor, small wire feed welder and misc. hand tools as necessary.  All are used conservatively and most turned off when not in use.  We will increase solar panels this year.  Excess energy is dumped to the water pump to pump to the storage tank rather than burn it off so batteries don't overcharge.  At times we have excess power even as is but not always when we want it.  I used automotive relays wired in series to do 24v switching for the pump.  The wind generator circuit is wired for a dump load if overcharging. I used the relays to switch the power to the pump and control a 220v transformer. ($400)

By doing it this way we use normal 110v electric supplies.  Kitchen stove, water heater, clothes drier (not  yet), extra refrigerator, all propane.

I figure payback is around $2400 per year but part of that is because we don't use what we would if we had it to waste.  Batteries last around 5 years avg.  I could do more with solar, compost water heater, hook up wife to bicycle powered clothes washer and battery charger, etc.  if I get the energy.
 :-/

[Bart_Cubbins]

Hi Shelley, I can't offer much advice on payback 'cause my property is completely off-grid and my cabin is still hypothetical anyway. For me, payback will mean being able to cook in my microwave and take a warm shower versus not.

But just some random thoughts to add to or reinforce some of the points Glenn made...

- Water pre-heating gives you the biggest bang for the buck and will pay for itself. Hydroelectric will generally pay for itself but not many people are lucky enough to have a suitable stream running through their property.

- The next biggest bang for the buck comes from conservation. It doesn't make financial sense to start spending on PV, batteries, inverters, etc. until you first do everything you can to minimize your electrical usage. Replace inefficient appliances, use fluorescents for general lighting and maybe LEDs for task and reading lights, get in the habit of turning off lights, put TV/DVD/VCR/microwave on switched outlets to eliminate the 'phantom' loads caused by clocks and instant-on power draws, replace CRTs with LCDs.

- After you do all that, you can start to think about whether investing in your own electricity generation is worthwhile. But determining payback is difficult because you can only guess at what energy costs will be in the future. Vojacek's electrical costs almost doubled in only five years. If you went with a grid-tie system, then payback also depends on what kind of net-metering program your utility has (i.e. can you build up credits during summer months and use them in winter?).

- Even if you can't justify it based on payback, there are other reasons you might want to go ahead anyway... the comfort of knowing that you are immune from power outages, that warm fuzzy green feeling, for the fun of it (hobby), or just because like Vojacek you're fed up with the electric company.

- For people who don't already own their property, one way to get payback is to buy off-grid land. The savings on the land will often pay for the home power systems.

Bart

[Shelley]

Thank you gentlemen.  Dovetails with what we thought.

[Amanda_931]

Agree with y'all.  (although I'm gathering that "useful life" on PV panels may well be quite a bit longer than stated, although the output is not as good as it was.)

Solar hot water is really wonderful.  Depending on how you do it.  And how good at scrounging you are.

I was almost hoping that the cost of putting mains electricity in up the hill would be prohibitive.  It's not.  But it might be a good idea to put a small, separate system-- full time for some of the lights, conceivably the refrigerator or freezer--for when ice storms or tornadoes disrupt the power.

There are people in this area who have mini-hydro.  Not on this property.  We're not in a good area for wind, AFIK.  Although it would be nice to try if the tower and installation didn't cost so much.

[melwynnd]

Hi,

We are already on grid, but are working toward more independence.  One of the major issues my husband and I have wrangled with is the fact that all of these systems(pv, wind, methane digester, etc.) require an investment of your time.  His stand is he doesn't want to mess with it.  Mine is that I'd rather spend my time working for myself than working for someone else to make money to pay for these things.  I also have the uncomfortable feeling some of these things won't be readily available in the future.  Does anyone else have this problem?

[John Raabe]

A very interesting thread with lots of good practical experience being shared.

My take is to do the simple inexpensive stuff first and then you can work up to the expensive, labor intensive things if the economics change (either on the fuel or production side of the equation).

What does that mean?
—1. Heat and water are primary. Have some control over these yourself. Have a wood stove if you have wood. Have a rainwater collection system. Have a generator or other means of powering a pump if you have your own well.
— 2. Have the house itself do as much natural heating and ventilation as possible to moderate your climate. Usually this will mean simple sun tempering, a little passive solar and good cross ventilation. These things are built into the building at little or no cost. Most of this is covered in the Sunkit http://www.countryplans.com/solarkit.htm.
— 3. If you have a place where you can keep water tanks from freezing, then an inline batch solar water heater will reduce the need for purchased fuel in most of the U.S. http://www.countryplans.com/Downloads/solar_wood_water.PDF.
— 4. From here on folks like Glenn and others have better advice... What might be best for you depends on lots of local conditions. The big ones, of course, are the cost of getting a grid hookup, heating fuel supply availability, your own tolerance for dependency on others, etc.

[glenn kangiser]

For one thing it does not cost as much if you are not in a hurry.  While the sine wave 4KW inverter cost $4000 new, I found a used one for $1800.  Some things run OK on a modified sine wave inverter  which costs around 1/2 as much but the problems with things that won't work or will burn out or work at low efficiency  on it aren't worth the trouble.

Since you can use normal appliances with it it would be possible to set up a small system separate to play with.  Grid tie inverters usually cost more.  I CA I am told that individuals can net meter- store what they use then pull it out later- but if they make extra it is given to the utility.  If you want to get CA rebates, you must tie into the grid, which means you must get permits because the power company won't look at your place until you return from the permit office.

As Amanda said, I think I have read that in 25 years, solar panels are usually still working although maybe at a bit less efficiency.

Next thing is - I know some of this stuff but get lazy and don't get after it - why don't I have my solar water preheater etc-- gotta make a plan and get it done.  Maybe I'll do that later.  Someday.  After I get caught up with my other stuff. :-/

[Larry]

We are off grid at our cabin and have been using a combination of solar and generator for the construction.  In my case it made sense because we don't have electric available.  We have been able to run a small concrete mixer, table saw, and all the normal construction stuff without much trouble.  Our goal at this point is to continue increasing our solar generation and reducing the generator usage.  As the folks above have said, it can be done, but it's not cheap.

[glenn kangiser]

Sounds like a good plan, Larry.  Even with the negative aspect of currently higher cost, to me it's worth it to be able to thumb my nose at the power company and not be dependent on them.  Too many years of being a victim.

[glenn kangiser]

Wind is another component of solar.  I just finished bringing home the last trailer load of windmill parts, pump and sucker rod for my 53' high 8' diameter Aermotor windmill - going for some of the old technology but -hey it works--  SOoooo-- who's the sucker now.

[Shelley]

Article in last Sunday paper here.  About a West Texas father/son who install and service Aeromotors.

Got all the business they can handle.  Ranchers are reviving their discarded ones.

Article mentioned something I didn't know.  Evidently only good for shallow water.  Said that they were only for 250' or less.  Love to have one anyway....just for the look.

[glenn kangiser]

Actually -if you want a big one- not common- and set it on short stroke- it is good for well over 1000' pumping depth.  Mine will be marginal but I think I can change a few things if necessary and get more depth and less water.  Here's specs.  Look for a used one- new ones will kill you in price.  Mine would work out to $8000 or so - got it for $800 and had to take it out-  parts will cost some and of course my labor is worth nothing.

http://www.aermotorwindmill.com/Sales/CommonQuestions.asp

[Amanda_931]

250' is a shallow well?

Around here the prospect would have us running screaming down to jump in the river, or something (people right next to the river often have a LOT of trouble finding water at all--although they may not be drilling past 250').

[glenn kangiser]

My well is a poor producer -solid rock with a couple fractures for water to come in. 1 gpm - I have my pump set at 320' and can pump it to that in about 45 minutes getting about a total of 300 - 400 gallons.  My well total depth is 675' and standing level is 169'  I will drop the electric pump on down to about 600' under the windmill which I will set about 280'.  The electric will pump through the windmill pipe-- hope I don't have to change it for a while. :-/

[Daddymem]

The term shallow well typically refers to a well that draws from the water table just below the ground but above the bedrock.  Some people call them shallow to bedrock wells since they go just about down to bedrock.  A bedrock well is drilled down into the bedrock where the water is supplied from the water found in the cracks throughout the bedrock.  Bedrock wells can get quite deep depending on the type of bedrock (how many cracks are in it) and where the water table sits.  

[glenn kangiser]

Making your own power may cost a bit more to get started but you really get satisfaction when things are going right.

Today we started up the hot tub- filtered the water a couple hours with the standard 220 1.5 hp pump -welded up the leg on the experimental solar trough water heater, continued heating the tub with the circulating pump and the wood fired 3000 lb cob bear water heater (masonry stove?), pumped a couple hundred gallons of water, and have our freezer and fridge running 24 hrs a day - all without starting the generator and without a payment to a power company.

We are currently running a Trace SW4024 - 4kw inverter, a 1000 watt wind generator (putting out like crazy today) and 1320 watts solar panels.

[glenn kangiser]

Solar cookers can be made in many shapes and forms.  Here my wife is cooking 2 steaks on our experimental parabolic trough hot tub heater.  It gets hot enough to set wood on fire.  It is 4' x 10' with a 30" focus.  These can be made as long as you like and have the ability to boil water if long enough.  This one is in series with the original cob bear hot tub heater and the newer wood boiler coil hot tub heater.  All will be routed to the cabin floor hydronic heating tubes next winter.

The steaks survived and actually were quite good.

.  

[blumergy(Guest)]

Hi, can you tell me what type of material you are using for the trough solar collector. Thank a bunch!

Solar cookers can be made in many shapes and forms.  Here my wife is cooking 2 steaks on our experimental parabolic trough hot tub heater.  It gets hot enough to set wood on fire.  It is 4' x 10' with a 30" focus.  These can be made as long as you like and have the ability to boil water if long enough.  This one is in series with the original cob bear hot tub heater and the newer wood boiler coil hot tub heater.  All will be routed to the cabin floor hydronic heating tubes next winter.

The steaks survived and actually were quite good.

.  

[glenn kangiser]

I used stainless mirror sheet for this one.  At the time a 4'x10' sheet was about $125.  This was experimental and to make one that would do a good job heating a hot tub you would need multiple sheets - .  Nice thing about these is that you can continue adding sections to 40' long or more if desired.  They usually run exactly east and west and must be adjusted north and south for sun angle change every few days or run a tracker.

A cheaper mirror can be made from something such as masonite with mirror chrome plastic glued to it.  I forget the name of the product.  It must be parabolic to focus all the heat in a narrow strip.  A half circle won't do.  There are programs for calculating the curve on the net - freeware.

[Texan lost in cali]

I think the payback is really about to begin. What happens if the peak oil guys are right? How much will propane cost you then, the delivery charge might be more than the propane. I have also been reading in the wall street journal that solar panels are becoming more scarce, not enough supply for the demand.

[Sassy]

We've had mostly clouds, rain & snow for the past month... we've only had to run the diesel generator a couple times during that period for 1-2 hrs.  When we don't have sun for our solar panels, we've had wind & our wind generator really kicks in.  With the wood stove added to that (we get our wood from fallen trees that friends, usually, want removed from their property) we've had all the power we've needed to run power tools, computers, microwave, lights etc & of course Glenn's speakers for his music at full blast   ...  (we have propane for our stove & tankless water heater - but use very little).  I made a quiche with eggs from our chickens, swiss chard, spinach, turnips, & cauliflower freshly picked from our rooftop garden--even with all the snow (had to buy the cheese - haven't gotten into making cheese yet - would like to learn when we are able to be here fulltime & have milk goats - don't grow our own wheat... ha) So, we're getting to the point where we are pretty self-sufficient & hopefully aren't affecting our surroundings too much...  

[Amanda_931]

Sounds lovely, Sassy.