Can I use a Wood Boiler instead of solar to charge batteries?

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mosshollowe

New Member
Jan 30, 2011
5
Upstate SC
I am new here and SO GLAD to find such a brain trust! Because for over 4 years, I've been trying to become my own "expert" on energy independence, and I've gotten nowhere fast, except maybe broke. After living in Wash. DC w/o power 2 weeks when the grid shut down, we saw how quickly things can get ugly. Then, we moved here to the mts. of SC, and ice storm knocked out our power for a week, and we discovered quickly that no power = no water (well pump). S-o-o-o-o-o...

We retrofitted radiant heat floor in crawlspace of our 3200 s.f. 1-story house, to supplement the existing heat pump. The radiant floor and DHW is heated with a standard electric water heater that has auxiliary solar hw attached, along with on demand Noritz propane tankless. This system is proving more expensive to run than promised, and only going to get worse. We have reasonable insulation (will be beefing up), and good pella windows.

We also installed backup batteries charged by the grid, and a propane generator that charges them when power goes out. This was mainly so we'd always have water in case of power outage. More than a day or so w/o power drains the batteries, and the propane generator is a propane hog. Obviously, batteries only help us in a short-term outage, but they run the well pump and a few circuits for fridge and lights. We have livestock so water is a must.

The plan was to someday add solar panels to charge the batteries to be independent of propane and grid, but they are just astronomical in price. Long story short, I ended up in this forum, simply because I started out thinking maybe we should add a fp insert to our living room fp, just in case things got really bad and we need some heat when propane and grid aren't available or too expensive (we're retiring and the way things are looking)... But, after finding this forum, I'm thinking a wood-fired boiler would be smart for all our heating needs... AND WOW, what if I could back up batteries, to boot???

But, I have not proven to be a very good self-proclaimed expert, and think I have made some expensive mistakes along the way. I don't mind spending some money in the short-term for a long-term gain, but at some point, I just want to GET THERE! Stop re-thinking all this and spend my limited energy and imagination on something else!

If anyone has any info, experience, or could point me somewhere where I can find such a person... PLEASE help me! Is there a wood fired boiler that would provide the main source of heat for my radiant floors and DHW, at least during the coldest months, still use my tankless for DHW during warm months, and also charge my batteries when the grid goes down? Is this too much to ask?

Even if I can't do it all with a wood burning boiler, I think I'd still like to add one to my current system, just to get off propane or electric for heat. At least as a back up or supplement. Any recommendations for that purpose would also be appreciated! I don't know if indoor or outdoor is better, but we have a small cellar where the batteries and water system are stored (advice in this regard is also appreciated).

Thanks!! I know I'm asking a lot, but any hints are appreciated!

Lynn of Moss Hollowe
The Dark Corner, SC
 
and also charge my batteries when the grid goes down

That is the problem, everything else is doable.

I have come across some people experimenting with this, a Stirling engine?, but it is very much a geek type thing, whether it will ever be commercially viable is another issue.

Grid Tied Solar PV is usually only economic if you can get massive subsidies. Presumably you can not? Things may change.

Then there is wind and water, both are very much location dependent.

First thing you will find out is that spending the money on insulation has the best payback, your heating load goes down along with the cost of a boiler and the expense on feeding it.

So you need to work out what your heating load will be after your improvements. Presumably you can use your current bills to work out your current spend.

I looked at a propane generator, but unless our supply becomes really unreliable the cost benefit just was not there. I also looked at PV. Only so much money and much higher priorities.
 
No time to get long winded here but do a search on Thermoelectric generators on this site and google. I don't know if this is practical as much as it is fanatical.
 
The whole back-up electricity game can be summarized easily.

If you want convenience, it costs more.

If you're talking about getting through an occasional power outage with minimal comfort. just get a good quality gasoline generator and learn to switch circuit breakers off and on as needed. Go out and choke and start it and go back in the house. They're not cheap and gas is expensive, yes, but for an occasional event it's cheapest.

If you want to push a button in the house and have the generator start (or have it come on automatically) then you're talking propane generator (no choke needed on a cold night). They don't cost much more than an equivalent gasoline model but the propane is more expensive to operate.

Solar electric and batteries are very very expensive if you want to run normal American residential loads.

If you want to prepare for armageddon....well, start learning to live without stuff. It will be a lot easier.
 
Google MCHP. Micro Combined Heat & Power. There are units out there not sure if there is a wood fired one, worth some www. time though.
 
Sigh... I was afraid it was too much to ask (I usually do ask for too much, just ask my husband)! I thank you all for the info on MCHP and Stirling Engines (which seem to be working together as a combined technology). I'd never heard of it. ...I have tried contacting Freewatts, which seems to be doing some stuff here in the US with residential applications, for info on their generators. Sounds interesting! But their "contact-us" link doesn't seem to be working on the website, so I'm already having doubts. I'll keep trying, tho. The price, from what little is available, seems about in line with PV panels, but seems like you would end up with more for your $, since it's providing heat also. Downside is in warm months, I guess...

Meanwhile, yep, we went for convenient, Dave, since our ultimate goal is to get as "off-grid" as possible. Not sure we can ever quite get there, but in any event, we want to be able to flip some switches in the comfort of indoors, rather than fumbling around outside in an ice storm at 2:00 a.m. when we're 80 years old! lol. But, it's a balancing act. Besides, we already had propane cooking so it seemed smart at the time!

SO, since I'm still thinking that a wood boiler is better for our needs than a fireplace insert in order to get some "off-grid" heat, a couple more questions:

Can the boiler be attached to BOTH the existing forced air system AND the radiant floor/DHW? Or, would I need to choose one or the other? I'm guessing I would need to choose (in which case, I would certainly choose the water), but just wondering, since I don't know how these things work or how they "attach" to the existing systems. Do I sound dumb, or what?

Also, what is the overall consensus on Outdoor boiler vs. Indoor? We are still flexible at this point, since we have a cellar it could go into, or, it go out just adjacent and outside that cellar, which is where our outdoor propane generator sits. It's also under a deck that needs to be demolished and rebuilt, and we could plan that in to the project somehow if outdoor is better.

Thanks again!

Lynn of Moss Hollowe
The Dark Corner, SC
 
I retired in 1989 and built here in 1990. The best money I ever spent was on the envelope of the house. It is relatively air tight and well insulated. I have been saving money for twenty years without having to turn a switch, operate a machine, or clean and maintain any device. The sealed cracks, openings and heavy insulation remain unnoticed doing their job year after year, summer and winter. It should continue long after I am gone.

If you have not already, get actual numbers on your house air changes and insulation. Money spent on the envelope should payback quite well. Or some other investment may be better for you.

Put all your energy consumption and expenditures on a spreadsheet for as many years as you have the data. You may be able to go to the utilities and get a history run on your property. They do that for free here. Get the detailed weather history for your location. Put that on the spreadsheet. Decide how many weeks you want to be viable in case of a power outage. Then life cycle cost every expenditure in light of what you currently spend and how it will contribute to your survival without power.

See if you can find a friend that is knowledgeable in building technology and life cycle costing. Perhaps you can barter with someone for the services or pay someone to teach you how to use the many tools available on the net to evaluate energy related investments. A good resource for me is the old farmers that live around here. They have generations of knowledge of how to do things in our area. Pick their brains while they are still around. Of many sad experiences, I am reminded of ten years ago when a friend called and asked me a question. I didn't know, but told I him would call him right back. Then I rang up my dad because I knew his cattle had done the same thing. When my mom answered, I remembered my dad had passed recently.

In this process you will find what works best for you. It may be different than what works best for others. And, to a large extent, you will reach a point where you are finally done with your preparations.
 
You could possibly put a steam coil in the burn chamber of a gassifier. You wouldn't have trouble producing steam there & running a small turbine to drive a generator. Obviously you would need to do a bunch of R&D, Randy
 
Google wood gas generators or gassifiers, this is another thing I am intrigued by, there are people out there generating electricity by burning wood, or should I say wood gas, also running cars and trucks on wood. Sounds strange, the Germans did it back in world war 1 they ran alot of there tanks and vehicles on wood, nothing new. Just like the gassification boiler not new, been around for decades just not here in the USA.

Steve
 
my next project might be a "brezzy" wind mill "grid connected" soon to be stand alone - might break even in twenty years - wasted lots of money on other stupid things. Cool home built unit!
 
Lynn,
Like Steve I respect history (necessity is the mother of invention), cheap energy prices have caused us to forget a lot of really good and practical ideas. Being from the Northeast where God stores our solar energy in wood, I too dream of making a CHP gasifier, a Cogeneration heat and power unit. Woodgas is doable for power http://wiki.gekgasifier.com/w/page/26543192/Operate-the-Power-Pallet. What keeps me awake at night is figuring how to hook my seton boiler up to my propane genset.
 
Wow, you guys, I was just going to post links to the GEK and victory gasifiers, but you beat me to it! Totally fascinating stuff!

Not being at all mechanical, I would of course need the GEK totally complete system (the "20kw GEK Power Pallet," found here: http://www.gekgasifier.com/), and with the price tag, I may as well go with PV panels. However, the appeal of the GEK to be able to generate electricity, heat, hot water AND charge my batteries...all with wood! It's stunning. Too bad it's not farther along (more people around who know what they're doing), since I'd definitely need someone who knows something about it to install and tweak, etc.

I wouldn't mind being a guinea pig, but I just don't have that someone available who could do the work! Heck, we spent TWO YEARS with the guy who installed our back up batteries and radiant floors, just to get that whole system to run correctly--and he had 20 years experience with his solar company and as a consultant to the gas company! What would my chances be of getting this "new" technology to work right.

Another possible minus (for me) is that it looks like it wouldn't burn logs, but chips or pellets... Ideally, I'd like to use the wood from our land, and chipping seems like it would be adding an extra step = more work and time.

...But still... pretty cool
 
The wood boiler can definitely do both radiant and hot air, as well as domestic hot water easily, and cooling and/or electricity if you want to get really complicated.

I'm not sure why a propane generator would be more expensive to run than gas. More $$$ to purchase and install, but propane is about equal to gasoline in $/btu here now, much cheaper in summer.

Jimbo is right on, any money you spend on Insulating and Weatherizing (look up the book by that title by Taunton Press) will keep paying back as long as the house is in use. Any money you spend on equipment will depreciate and have to be maintained. Given your climate and closeness to retirement it's hard to see how a wood boiler would make a lot of sense, unless it's a hobby you think you would enjoy.

With the radiant system that's costing more than expected, is the electric water heater hooked up or is it using the propane water heater? How many and what kind of panels do you have hooked to the solar tank? I'm assuming you have a glycol/antifreeze solar loop that heats the electric water tank that circulates the potable water though the radiant tubes, in which case you have a heat exchanger and then probably staple up radiant, which means that the solar has to heat the water pretty hot to get any heat through all those steps.

When you start talking about power in end times scenarios it gets pretty hard to predict what will be most convienient. I'd certainly want PV if I needed electrical power, but only if I could find them without the mark of the beast.
 
The wood boiler can definitely do both radiant and hot air, as well as domestic hot water easily, and cooling and/or electricity if you want to get really complicated.
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WOW! Redundant to do both heats, but I'm so intrigued by cooling and electricity! I don't mind complicated--if it just works! Wonder where I could find someone in this area, just to pick his brain and explore feasibility...

I’m not sure why a propane generator would be more expensive to run than gas.
Click to expand...

Well, I don't know if it's more expensive--it's just that we're not realizing any significant efficiency/savings over what we had before. We had Great Expectations. I think we're losing from the floors into the crawlspace, but 2 insulation companies told us it's fine. They agree we should beef up the attic, but wasting money in the crawlspace. I'm still not convinced, but....? I want to spend $$ wisely, and they're the experts. I will say that the back up system, once all the bugs worked out, is working like a dream, so that's a plus. But realistically, it's a short-term convenience.

Given your climate and closeness to retirement it’s hard to see how a wood boiler would make a lot of sense, unless it’s a hobby you think you would enjoy.
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Are wood boilers that difficult to use and maintain--would you mind expanding on why it doesn't make sense? Want to know everything I'm getting into. If there's a better way, that's what I seek! Are you thinking fp insert is wiser? Or something else? Our radiant floors struggle to keep the house at 62F when it's in the tens and teens outside, esp. if the wind is howling. We usually use the heat pump to take up the slack to be comfortable. A tank of propane lasts us half a year+/-. If we go without power more than a day, and the generator has to run several hours, we'd burn through that tank in no time.

I agree it's probably an extra chore we don't need, but oil prices aren't near the highs we're going to see. If US is no longer the largest consumer of energy, we'll no longer get best price. The middle east, the devalued dollar, failing stock market, bankrupt social security, but, whatever--economy recovers or not--dollars are going down and oil is going up. We are spending too much NOW on heating, so the future? Yikes. I don't like to be cold, and we have plenty of free wood. And, if we're going to do something, now is the time to do it, while we can still afford it. Might as well make it efficient and/or self sustainable if possible.

With the radiant system that’s costing more than expected, is the electric water heater hooked up or is it using the propane water heater? How many and what kind of panels do you have hooked to the solar tank? I’m assuming you have a glycol/antifreeze solar loop that heats the electric water tank that circulates the potable water though the radiant tubes, in which case you have a heat exchanger and then probably staple up radiant, which means that the solar has to heat the water pretty hot to get any heat through all those steps.
Click to expand...

Two solar panels, and yes, loop and heat exchanger. We've tried keeping the hw heater off, and we've tried it with it on. In the winter, I can hear that tankless coming on all the time when the hw is off. We're not sure what the max efficiency combination is, I just know we've spent a lot and little or no better off efficiency wise, while still dependent on grid and propane. I wouldn't mind so much, if we were at least self sufficient, but we're none of the above. But maybe we're closer than I think, with the addition of a wood boiler? Then the propane would be solely for battery charging and cooking, lasting much longer. At least, we could always be warm. Just wish it could also solve our well pump issue (which is why we got the batteries in the first place).

When you start talking about power in end times scenarios it gets pretty hard to predict what will be most convienient. I’d certainly want PV if I needed electrical power, but only if I could find them without the mark of the beast.
Click to expand...

lol, which ones have the mark and which ones don't?! I've always been a self-sufficiency type and off-grid wannabe, even before this economic mess. Besides (by my standards), I'm still fairly young (51), and my husband is 63. We're planning ahead (maybe not planning well, but planning nonetheless)... But, you're right, no one can predict what a desperate government will do in desperate times. It has been illegal to cut and burn your own wood or even to own gold. Forced rotating blackouts, to save on energy demands.

After seeing first hand what happens during a SHORT blackout (when a tree in OH (TN?) knocked out power to the entire seaboard, some were out 4-6 weeks), grocery stores sell out within a few days--if they can even open--gas stations can't pump, trucks can't deliver new supplies (no propane if I needed it)--EVERYTHING just STOPS. We were in an all-electric house at the time, with no backup. Water was a problem--you were told to boil it, since the treatment plant was shut down. How was I supposed to boil it? Buy it? Good luck! The news reported that our entire power grid is so vulnerable and archaic that it was surprising it didn't happen more often. The News--not the wingnuts. I don't think many improvements have been made since.

On 9/11, we could see the smoke from the Pentagon 4 miles away. We also had 2 mos. of ducking and diving every time you filled up the gas tank (we felt silly doing it--but everyone did! lol) when John Muhammad the DC sniper was shooting people at gas stations. Hurricane Isabel flooded the Potomac River and shut down everything for over a week. Enough.

I don't know about Armageddon, and our experiences were small-potatoes, local-scale stuff, but that's when I seriously started playing the game, "what would we do if...?" So, my first concern was water. Now, after posing the question, "what if a serious black out occurred and I needed heat/propane?" which led to fp. insert, which led me to this forum, which led to wood boiler... Could it be as simple as that (hopefully)?

Out of curiosity, if you could have anything you wanted, you would choose PV over wood-boiler for electricity? Seems like if I could add only one system to do both, it would be better. Maybe that's just too much demand from one system?
 
I was at a friends house yesterday, 5,200 sq ft off grid. Now we do have sunshine, but the high tomorrow will be 0 or thereabouts.

He has PV for electric, wood stoves for heating, 4 of them but rairly uses more than one and gets through 8 cords a year. He does have propane as a back up and you need something for when you are not there.

If I was looking long term etc and starting from scratch it is quite possible to build nowadays a house with very limited heating requirements, a small stove and solar pv/ solar hw would do it.

I doubt if they use half the house they have, even if you want lots of space 2,000ft would more than do it, I lived in 830sq ft for 15 years.

Cooking would be the tricky bit, I like gas, electric is too much for PV systems, a wood cook stove would be the best option.

Now if you could economically turn wood into syn gas and then store it like Propane, that would be interesting.
 
I'm a long way away and I don't do this full time, so it's easy to give an opinion because there's no way there's any consequence for me. You asked about certain possibilities and you'll get lots of answers, I'll give one opinion of what is practical and what isn't. Wood powered electricity and cooling are not feasible for anyone who is not an engineer or obsessive tinkerer. I like the idea of combined heat and electrical power, maybe someday I'll build the turbocharged boiler that will do it, just haven't found the time yet.

Yes, you can generate electricity from a wood boiler in at least a couple of ways, none of which are "off the shelf". You could also distill methanol out of the gas and drive your car with it, if you want to do that sort of thing. PV on the other hand is something that has developed to the point that it is a reliable system that you can get "off the shelf" (or mail order these days), or find an installer that will install a system that works the first time.

The solar/radiant should have been the sort of thing that would work the first time, but I don't know any of the details so I'll hold off on saying the installer you had was incompetent. Your installer was wrong if he said that two panels would lower your winter heating costs in addition to heating your water. It sounds like a good hot water system, but there just isn't any heat left, except maybe in fall and spring, to do any heating, especially through that setup. Solar hot water is a particularly good complement to wood heat and hot water, as there should be no shortage of hot water through the summer to keep from burning wood in the summer for hot water.

If you're looking to save money, the obvious upgrades are the insulation/weatherizing: air sealing, insulating the crawlspace under the radiant, air sealing and adding insulation to the attic. Using the heat pump is probably cheaper than propane, especially if it's burned in an instantaneous water heater not a high efficiency furnace, you can find calculators online to give you a better idea of the costs.

The boiler will provide hot air, radiant and DHW "off the shelf" and could cost somewhere in the ballpark of $10-20,000 depending on how much work you want to do and how good of an installer you can locate. Then there is the ongoing work of feeding the beast, which could be minor for retirees as young as yourselves, when I was a kid we cut wood once or twice a year for a small new house. On the other hand if this is a "preparedness" move, then a boiler that relies on electricity and a wood gathering system that relies on equipment and oil is not going to do much good, you'll be better off with a wood cook stove to keep the kitchen warm and the rest of the house from freezing. A masonry heater might fill the heat needs, I'm not familiar with the issues they have in your climate.

You won't get any argument here on the shortsightedness of burning petroleum for heat, or the fragility of our economic system. But when I'm out on an all night zombie patrol, I'm not going to be worrying if the wife has hot water.
 
IMHO the first step (leap???) we need to to take to scale back is to consider living in a house of 1,000 sq. ft. or less. They've been doing it in Europe forever and I beleive most of us were probably raised in that amount of space along with 1.2 siblings plus 3 or 4 extras! Come up with a good efficient design, put your ego in check and throw out yer junk, you'll be happy you did!
 
Now if you could economically turn wood into syn gas and then store it like Propane, that would be interesting.

 Signature 
David

At one point in our history most sizable communities had a gasworks for "town gas" used for lights and cooking. They must have stored it.
 
shortline said:
Now if you could economically turn wood into syn gas and then store it like Propane, that would be interesting.

 Signature 
David

At one point in our history most sizable communities had a gasworks for "town gas" used for lights and cooking. They must have stored it.
Click to expand...

History? I remember them well, coal gas.

Sort of like an inverted cup on top of a cup, slid on each other.

And then came natural gas.
 
I wonder if you could run a generator off the wood gas in a gasser primary chamber? Forced draft might be some easier than induced, although the engine should pull the gas through regardless(I'm sure the mixture won't be perfect, might run though). All it would take is a pipe nipple in the door & a hose to the carb., Randy
 
Mosshollowe and Singend Eybrows (and all other interested parties),
FEMA has a free download for using a gasifier for running a motor and production of electricity. "Supposedly" it's not that dificult to build a gasifier if you have the correct plans. In Europe before the introdcution to petroleum products "production gas" was used to fuel city lights in some major cities in Europe. Likewise in WW2 many european autos and farm tractors were converted to gasification fuel because petroleum products were scarce to unavailable. Knowing the right size gasifier for production is the key. You totally eliminate the secondary combustion (turn off air or build a unit with no air to secondary. the fumes have to be cooled so they wont ignite when air is introduced) to use the gasses to run the engine. Downdraft gassers are best for this application because they supply a cleaner fuel source. Using a water cooled engine in this application can supply the hot water needed for heating the home. It can be quite an integrated system but coupled with solar and or wind it can lead to a possibly 100% off the grid experience. Probably find the FEMA link going to US.Gov/FEMA/gasifier or something close to that. A word of caution though is the gasses from a gasifier include carbonmonoxide and breathing it is deadly.
 
I've been casually looking for a wrecked Toyota Prius for a homestead powerplant.
Supposedly a fully charged hybrid battery will run an average home for
several days. It would take a sizeable inverter but I have seen others adapt
their everyday drivers for standby use Just a thought.. MM
 
Some other places to look into gasifier supplied electrical energy are google and ebay. A small 4 banger would probably work real well but I think some of the newer cars with computers will foil a gasification project so in this case I think older might be better. I have been rumminating the idea of building my own gasifier, one that would do double duty as a fuel source for a generator and as a source of heat. It could be a sizable investment if looked at short term but my electric bill is already near $100 monthly. MMx2.. Thx for the input mtnmizer.
 
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