Wondering about a great new energy-saving device
you found on the Internet? Then CLICK HERE!
Sorry. Jeff no longer answers questions online.
This will remain as a searchable
resource for all BHM website visitors.
Archive for the ‘Fuel’ Category
Friday, May 22nd, 2009
Do you have any experience with propane refrigerators? If so, what model small refrigerator do you recommend for a small cabin that will be used year-round?
Thanks so much,
We have included propane refrigerators and freezers on many solar off-grid homes, but since most are based on heating a gas to cause the cooling cycle, I would not use them in an application where the home is not occupied for many parts of the year like a typical weekend cabin. After the first few years there are some maintenance issues that you need to take care of to keep them operating properly, and they do use a lot of propane.
We have switched to the 12/24 VDC small 50 liter refrigerator or the larger 8 cu.ft. top load freezer by SunDanzer that operate from solar charged battery. They require very little solar power to operate due to their very heavy wall insulation, and do not use a flame like the propane units. I think if properly installed they are a much safer and offer a longer life solution, although they are more expensive.
Thank you for your quick reply
If you do not mind another question, I am wondering what brand of 50 liter refrigerator would you recommend? And, pardon my ignorance, but what does the “V” in VDC mean? Does it mean voltage?
You can see I am at the beginning of the learning curve relative to using solar energy/alternative energy sources to achieve energy independence for a small cabin.
SunFrost and SunDanzer both make really great super-efficient DC refrigerators and freezers. All SunFrost models are stand-up designs, and all SunDanzer models are top load. You may like the stand up version better, but they are pricey.
I have worked with both for almost 15 years and each has their advantages. Up until this year, the SunDanzer units were in the 8 cu.ft. range which is fairly large. This spring they came out with a 50 liter unit which I found to be perfect for a week-end cabin type application due to the small size and very small battery usage. However, it’s a top load and must be ordered either as a freezer or a refrigerator, but not both.
When we say “VDC” we mean “volts DC”.
Click Here for ome other useful solar terms
Hope that helps.
Thursday, May 14th, 2009
I am looking at replacing a traditional fireplace with a wood stove insert that can be used in a hydronic floor system.
I looked over your article on the fireplace you installed in your home and have spoke to and web searched for wood stoves that circulate water for heated floors and find only the “long burners” for outside or commercial “furnaces”, nothing that would be appropriate for a great room/ranch application. Can you point me toward manufacturers that have this type of product?
Mark J. Bechtel
As I mentioned in answers to similar questions to this web site, most of these manufacturers have gone out of business due to not being able to meet new regulations and codes related to wood-fired boilers. There are several web sites that describe how to build your own, but installers are switching to the outdoor models for safety.
I feel our hydronic fireplace system is very safe, but I have included both a temperature and a separate pressure relief valve, and a way to keep the pump working if there is a power outage. Many of these early systems were well made but the piping systems were poorly designed and installed.
Hope this helps,
Wednesday, March 25th, 2009
I have a situation not completely unlike Blake McKinney’s cabin (issue 83) in that I am planning an off grid cabin that will only be used once in awhile — in northern Wisconsin! Was considering solar hot water (closed glycol system) that might be able to be integrated into a radiant infloor (also with glycol) system to keep the house/plumbing from freezing when no one there. Do you think this is reasonable? Electric to run the pump would be from PV modules/battery bank. Would you still recommend a propane wall heater as backup?
We would use a high efficiency wood stove to heat home when occupied.
Our solar exposure is considerably better than the McKinney place.
Also, do you know of any remote monitoring system for house temperature, etc that could use cell phone signal to communicate info back to us at our main residence 90 miles away? :)
Finally, is it generally recommended to NOT let your propane generator automatically switch on to recharge the batteries when no one is around?
Thanks a bunch,
That’s a lot of questions!
I would not recommend trying to heat a home with an active solar system for long periods of the winter when nobody is home. There are too many little things that can turn into big things when nobody is there to correct. For example, a big snow can cover the solar array for days if nobody is there to clear them off. A pump could fail, or the system could leak. Even a small leak of a sealed antifreeze system will cause makeup water to enter and could cause the now antifreeze in the loop to freeze.
I would deal with this in one of two ways. Either design a passive solar home that has enough thermal mass to keep from freezing at night, or design all the plumbing to slope to 2 or 3 low points where you can completely drain all the piping before you leave. Blankets and sheets on beds and clothing in closets will become “musty” under these conditions so I would strip the beds and remove anything that could be damaged from the cold and/or dampness.
I would not leave a generator on automatic start if I was going to be gone longer than a weekend as a simple control glitch or battery problem could cause the generator to run until it ran the tank dry.
There are now all kinds of remote Internet and wireless phone based controls to allow monitoring of remote homes and businesses. We have inverters that will send an email to the installer if there is a problem, and there are Internet based cameras that will send you live video of inside your home if the alarm is activated or there is a water leak.
I suggest that you keep it simple. If the pipes are dry and you remove anything that can be damaged from the cold, why spend all that money to heat someplace you will not be for months at a time.
Sunday, March 22nd, 2009
I purchased a Central model 2300 wood boiler with propane backup.
I am located in Butte, Montana and the normal wood of choice is Pine.
The wood burning part seems to work sort of adequate, although the fire frequently goes out. The main problem is the creosote that collects on everything inside the fire box. The propane gas nozzle has an electrode on the end of the gas nozzle which sticks inside the firebox. However, due to the creosote collecting on the end of the gas nozzle, it normally does not work after a week or so after I clean it.
In other words, it is pretty iffy, if the gas backup is going to fire or not. The creosote is so thick is makes a black sticky mass that covers the entire end of the gas nozzle.
Central has worked with me to correct the problem. They had me install a larger combustion fan that they felt wood keep the coals alive which should keep the creosote down plus they sent a new gas burner nozzle with electrode. All of these are nice but it fails to permanently fix the problem. It is hard to work with Central Boiler directly as they want you to work through the distributor that I bought it from.
I paid a little over 13,000 for the unit and I cannot count on the gas to backup the wood.
I have only had it in operation since November 2008 and have worked on it and worked on it. It has been a disaster.
I would like to get my money back and buy just a normal boiler but not sure how to approach that subject. If it would work, I would love to keep it, but this is almost ridiculous. I have asked my distributor for names of others that may have similar problems so that I could contact and possibly find solutions, but they have not and will not provide that info.
I do not want to get into the middle of any problems you are having with your wood fired boiler. However, I will be glad to review several choices that you might consider.
1. There is still the chance you may be able to at least turn the boiler back in for some type of partial credit, especially if you made it clear that you were going to be burning only pine and the dealer indicated this was not going to be a problem. A written letter to the manufacturer works far better than an email or phone call. I would make them aware of the problems you are having and include some photos, and explain you are not receiving any assistance from their local rep. At a minimum I would insist on the dealer coming out and checking all the controls and combustion chamber for proper operation.
2. I have a feeling that the written literature on the boiler advised that these were mainly intended for hardwood like oak, which do not have anywhere the problems with creosote buildup that you are experiencing. If this was the case, you might want to offer it for sale on the Internet in like new condition to someone located where hardwood is easier to find.
3. You could install a standard high efficiency propane boiler for “normal” home heating, and leave the wood boiler for when you can get a better mix of wood to burn, or use only for emergencies like when you run out of propane.
Hope this helps,
Monday, March 9th, 2009
I’ve read all the hydronic related postings I could find on your site but I didn’t find anything specific to my needs.
I live off the grid in Alaska and am fortunate to live in an area where I have access to all the bituminous coal I need for free. I’m wanting to use a hand stoked coal boiler in my garage to heat the garage and the rest of the house (approx 2200 sq ft everything included). I understand the concept behind a closed loop system and its components but I am curious if you think there is any merit to an open loop system.
My thought is a coal boiler with a large capacity (50-100 gal or larger tank) that is vented to atmosphere. The idea being that in the event of my electrical system going down and the circ pump not running or zone valves opening, the boiler (having a burn time of 12-18 hours) would simply relieve excessive heat and pressure by venting to atmosphere (outside) and in effect slowly boiling off the water or antifreeze but not so much that it goes dry and results in a catestrophic meltdown. I would still include a PRV just incase something obstructs the open air vent. Ultimately I just don’t want to rely on the pumps and cold water make up to save me from a meltdown.
Am I on to something or is this crazy and I just don’t know it?
Thank you for your time, you do a great job with your column!
You’re not crazy and there are many out there heating with coal. I worked for many years in West Virginia and Kentucky, and in the more rural mountain areas you could find coal almost anywhere. Kids could pick up all their parents needed to heat a house just by walking along the railroad tracks as the hundreds of over-flowing coal cars that passed by each day lost those pieces piled too high. People tend to heat with the fuel that is the most plentiful in their immediate area.
There is no question that a closed loop hot water boiler system under pressure will require more safety devices to prevent a high pressure blow-out, but there are thousands and thousands of these systems all over the world that have worked perfectly for many years using many different fuels. If loss of power is a concern, it would be easy to add a battery backup supply since the circulating pump and any motorized zone valves will require very little power to keep running. Some system manufacturers offer an optional DC pump that is piped right next to the AC pump, and can be quickly valved over if the AC pump fails or looses power.
All pressurized hydronic heating loops and boilers have more than one pressure relief device and in most cases a power failure during a roaring fire just means the boiler will start converting some of the water in the boiler to steam which gets vented out one of the relief valves. As soon as this starts, the auto-fill valve will sense the loss of water and let in more makeup water which will cool down the process for a few minutes. This cycle will repeat several times until you can bank the fire down or the power comes back on.
I agree that an open pressure hot water boiler might be easier to maintain and there are many now being made as a complete package. They look like a small outhouse, and all you need is a supply and return line from the unit to the hydronic heating system in your nearby house. Unfortunately, your problem will not be which type unit to buy – open or closed loop. Your problem is coal burns much hotter than wood and has more smoke issues than wood. Many wood fired boilers do not have cast iron grates or fire-box liners which are better at containing the hotter coal fire. Also, unlike wood smoke, coal contains different amounts of sulfur, depending on the seam of coal being mined, and if you have never caught a whiff of the smoke off a nearby coal fire you don’t know what I am talking about.
This means you will need to make sure the alternative fuel boiler you select is either designed to burn coal, or has optional equipment to allow it to burn coal. However, if you are in a very cold area and coal is free, then I believe it will be worth the effort for you to make this happen. Let us know how it worked out.
Tuesday, March 3rd, 2009
I have a lot of acreage we are clearing and hate just piling up the wood to be burnt as waste.
I have a large chipper and would like to instead chip the wood and store it for use in a wood gas setup to power a gas generator (25KW) to power the main home and out buildings. Everywhere I look there is a lot of information on wood gas but nothing much on using it with a gas generator. We really only need 8KW but with peak draws and lower output from the wood gas vs real gas I would prefer to be a little oversized.
Any info you can throw my way would be greatly appreciated.
The reason you are having problems finding information is this is a very complex process to setup and very costly to oeprate and maintain. Most successful systems are large scale with large gasifiers and generators.
Here are a few links to help you get started:
Hope this helps,
Tuesday, February 17th, 2009
Any truth to the claims of adding water injection systems to increase my mileage for my gas-guzzling SUV?
West Palm Beach, Fl
I am no expert on automobile engines, but I do know two things:
1. You can find 1000 different gadgets claiming increased mileage including wrapping magnets around the fuel line, injecting water, all kinds of fuel additives, coils to make a hotter spark, hotter spark plugs, and slicker lubricating oils.
2. If I manufactured low mileage cars in today’s high fuel cost environment causing many buyers to switch away from the “gas guzzlers”, I think I would be adding any gadget I could to make my design more efficient unless I had already tested and found all these gimmicks to either have little or no improvement, or their improvement caused long term engine damage.
You should read the opening paragraphs of an article I wrote last year.
Hope this helps,
Monday, February 9th, 2009
I’m considering buying a backup generator. I have street LNG to the house. I assume since it always has pressure, as long as suppliers don’t shut it off, I’d be ok. But if there were a period of extreme social disruption, suppliers may do just that, in which case the unit would be useless. I could go with a liquid fuel unit, but don’t really want to store fuel. What’s your opinion on the disruption problem? The 1st on-line sizing calculator I found says I need a 17.5 kW generator.
I was a boy-scout, so I always believe in their motto – “Be prepared”. Having said that, I do not know how big your house is, but a 17.5 kW generator is REALLY big for a home, unless it is all electric with 2 or more heat pumps. We have found a generator in the 8 kW range will handle everything in a typical home except air conditioning or electric heating. This size unit will easily power all lights, kitchen appliances, big screen TV and audio equipment, freezer, micro-wave oven, and well pump. It will also power your furnace fan if you have gas heat, but will be on the edge if you also try to power a heat pump or AC unit. Going up to a 12 kW generator will usually power all of the above, plus one fair sized heat pump or air conditioner.
I have many clients with homes having 4 or more heat pumps or AC units due to the large size of their home. I always tell them to decide what parts of the house they really need during an extended emergency and only heat or cool those spaces. This will not only reduce the size generator needed, but also the fuel since most generators use almost the same fuel at half loaded as full, so a over-sized generator only lightly loaded will usually use more fuel than a generator sized better to match the load.
As far as emergencies go, usually natural gas from the local utility is more reliable and available during storm related power outages, but there are times during line breaks or peak loads in the winter when line pressures drop. Any generator designed for natural gas can be easily converted over to run on propane. The Kohler line which I favor has a manifold block that has 2 pipe plugs, which are moved from one port to another to change over from propane to natural gas. It would be fairly easy to make a piping arrangement to allow a quick disconnect from the city line to a line from a underground propane tank, but I would make sure you are using a piping connection that must be first disconnected from one supply before connecting to the other or you could have a very dangerous situation if high pressure propane gas passed into the lower pressure city gas line.
If this is a real concern why not just keep the generator connected to a underground 500 or 1000 gal propane tank? Propane fuel does not go stale like gasoline, and you generator will always be ready as long as you run it every few weeks to keep it lubricated and battery charged.