R-pod Owners Forum Homepage

This site is free to use.
Donations benefit a non-profit Girls Softball organization

Forum Home Forum Home > R-pod Discussion Forums > Miscellaneous / Off-topic
  New Posts New Posts RSS Feed: Renewable propane
  FAQ FAQ  Forum Search   Calendar   Register Register  Login Login

Renewable propane
 Post Reply Post Reply Page  123 4>
Author
Message Reverse Sort Order
  Share Topic Share Topic  Topic Search Topic Search  Topic Options Topic Options
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290 		Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Topic: Renewable propane
    Posted: 01 Nov 2022 at 2:51pm
Yep, probably the European biomass furnaces have been modified from what were once coal furnaces to burn biomass solid fuels. Coal is strongly frowned upon in most of Europe these days, although it still provides about 10% of European energy requirements. I'm sure they wish it was more since the Russian natural gas cutoff. 
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
Back to Top
StephenH View Drop Down
podders Helping podders - pHp
podders Helping podders - pHp
Avatar

Joined: 29 Nov 2015
Location: Wake Forest, NC
Online Status: Offline
Posts: 6289 		Post Options Post Options   Quote StephenH Quote  Post ReplyReply Direct Link To This Post Posted: 01 Nov 2022 at 1:08pm
Kind of like a coal stove, but using various wood products instead.
StephenH
Happy is the man that findeth wisdom,...

ouR escaPOD mods
Former RPod 179
Current Cherokee Grey Wolf 24 JS
Back to Top
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290 		Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Posted: 01 Nov 2022 at 6:41am
A lot of folks around my area have outdoor wood furnaces and love them. They are quite sophisticated nowadays, they had to be reengineered to meet the stringent new EPA standards. That also makes them pretty expensive. The new ones have microprocessor controlled dampers and use some water based  thermal storage to levelize output  so can generate heat as demanded by the home HVAC system. And they have large fireboxes so you can load them infrequently and with large pieces of firewood (less cutting and splitting to do). All the wood, smoke  and soot mess, creosote and chimney fire risk stays outside the house which is nice.

The downsides are that the cost and effort to install these isn't trivial. Besides the boiler itself you need to install either a water to air heat exchanger in your air handler, or hydronic radiators, or radiant floor heating, the first option being the easiest if you have existing ductwork. And you need to run a set of insulated pipes with a circulating pump from the boiler to the heat exchanger(s). The other downside is that you don't get to enjoy looking at the fire in your living room. Also you need to either run the boiler  all the time when it's cold out or use antifreeze in the water loop. An indoor pellet stove has many of the same cleanliness and ease of use  advantages and is much less expensive but then you have to buy the pellets. 

So overall if you have a free or  inexpensive source of wood and plan on heating full time with it these can be a  good choice in a rural area.  You can still keep your indoor wood stove or fireplace for fire viewing. Not sure I'd install one in a suburban location even if allowed because of risk of it getting banned down the road due to particulate pollution. 

In my case I don't think I'm going to want to hear with wood exclusively as I get older. And I picked up a glass door water stove inexpensively  which I can install and connect to a heat exchanger in my air handler and possibly some thermal storage. With a high efficiency heat pump as my base heating that will give me wood heating as much as I want and still let me view the fire. 

Just my observations, everyone's needs are different. One alternative they have in northern Europe is residential multi fuel (wood pellets, wood chips, even switchgrass (which is an interesting biomass fuel) burners combined with bulk solid fuel  delivery. The furnaces are similar to a pellet stove but instead of storing and handling bags of pellets  you have a wood pellet or chip storage bin in your basement which a supplier comes and fills as required.  There is an automated auger system to deliver the pellets/chips and stoke the boiler. Pretty interesting alternative but we don't have it here. 
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
Back to Top
StephenH View Drop Down
podders Helping podders - pHp
podders Helping podders - pHp
Avatar

Joined: 29 Nov 2015
Location: Wake Forest, NC
Online Status: Offline
Posts: 6289 		Post Options Post Options   Quote StephenH Quote  Post ReplyReply Direct Link To This Post Posted: 31 Oct 2022 at 7:30pm
A lot depends on one's situation. I might lean more toward a heat pump if I had oil or propane as the fuel source. The experience with the heat pump was in a rental where the landlord was certainly not concerned with how efficient the system was.

The place my parents used to live (Forest Lake Estates in Zephyrhills, FL) used a pond as a source for heating the swimming pool, so I am familiar with that. They said it saved the park a lot of money.

What did you think of the Classic Edge Titanium HDX outdoor furnace I linked?
StephenH
Happy is the man that findeth wisdom,...

ouR escaPOD mods
Former RPod 179
Current Cherokee Grey Wolf 24 JS
Back to Top
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290 		Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Posted: 31 Oct 2022 at 10:04am
I too have experienced the limitations of the older style heat pumps. In fact, I still have one right now, and my electric usage spikes in mid winter  even though I also have a wood stove as well.  I'm getting rid of it next year.

But times change, and technology progresses, so what was true 20 or ever 10 or even 5 years ago may be incorrect now. We all have to step up to the challenge to keep up to date. Heat pumps are one of those tech areas. Solar is another.

As for cooling, that is of course simply running a heat pump in reverse, extracting heat from the inside air and dumping it into outside air. So either way, the heat pump efficiency follows the same thermodynamic formula. (It also turns out to be the same formula as in a heat engine, but inverted). For a heat pump theoretical efficiency is Thot/(Thot-Tcold) and for air conditioning it is Tcold/(Thot-Tcold) where T is absolute temperature. Since Thot-Tcold (also known as delta T) is a much smaller number than the absolute hot or cold temperature itself we can get phenomenally good efficiencies out of heat pumps and air conditioners. 

The numbers get better the smaller that temp differential is. And, the differential is much smaller for summer cooling than it is for winter heating. If say it's 100 degrees out and you have your tstat set at  say 80 that's only 20 degrees delta T. Compare that to a typical winter heating scenario where it's 20 degrees out and your tstat is set at 70, a 50 degree spread. 

You see where this is heading? The point is that the benefit in reducing the temp you're pumping heat to is much less  in summer than the benefit in raising it is in winter, because the summer delta T is not very large to begin with. So, if it doesn't pay to install geothermal for winter heating it won't pay to install it for summer cooling either. 

For me personally living in the mountains  the summer cooling requirement is negligible. Propane is expensive, I have no access to natural gas  and don't want to be spending money on or burning fossil fuel anyway.  I would still personally consider installing a "geothermal" water source heat pump for winter if I had a nearby pond that was big enough to act as a heat source/sink for the system. Then it's just a matter of tossing a big coil of plastic pipe in the pond to act as a heat exchanger. Although water source heat pumps are more expensive than air source ones at least you don't have all the expense of burying the ground source loop, and the loop is much shorter because the heat exchange between it and water is much better than with soil. But lacking a large pond I'm going with a hybrid solar powered mini split/wood heat solution . Mini splits look fine to me. I don't have to heat or cool rooms I'm not using. What I don't like are noisy air handlers and compressors in centrdl systems.  Both the inside and outside mini split units are very quiet. 
 
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
Back to Top
jato View Drop Down
Senior Member
Senior Member
Avatar

Joined: 23 Feb 2012
Location: Kewadin, MI
Online Status: Offline
Posts: 3227 		Post Options Post Options   Quote jato Quote  Post ReplyReply Direct Link To This Post Posted: 30 Oct 2022 at 6:18pm
Originally posted by mjlrpod

I use a pellet stove. I cant say enough good things about it. Mine is a Harmon fireplace insert. I never use the boiler in the house, unless I choose too. I burn nothing but douglass fir pellets and can go 2 weeks or more in the absolute dead of winter without emptying ash ashpan. Really good system, except you need to buy pellets. I don't have any neighbors saying " hey a pallet of pellets fell in my yard, wanna come get it?" 


The Harmon is a great stove.  We purchased our Harmon TL 200 in October 2002 and it still runs like a champ.  We love the glass window in front as well as the outside air used for combustion.  We use about 4 cords during the winter here in northern Michigan.  Usually start wood burning mid-November to about mid-April.  The only thing we replace on a somewhat regular basis, about every 5 years is the ceramic fiber afterburner which runs about $ 250.
God's pod
'11 model 177
'17 Ford F-150 4WD 3.5 Ecoboost
Jim and Diane by beautiful Torch Lake
"...and you will know the Truth and the Truth will set you free."
Back to Top
StephenH View Drop Down
podders Helping podders - pHp
podders Helping podders - pHp
Avatar

Joined: 29 Nov 2015
Location: Wake Forest, NC
Online Status: Offline
Posts: 6289 		Post Options Post Options   Quote StephenH Quote  Post ReplyReply Direct Link To This Post Posted: 30 Oct 2022 at 5:45pm
Yes, I keep referencing the old technology. It is what I experienced. I  did say this, "I would say that if the situation is such that air source would work, then go for it. If not, then ground source is a great option. It is also good for those scorcher days when the air temperature is hot since the heat pump would have a much cooler place to dump the heat from the house. That is the other half of the heating/cooling problem which has not been addressed so far in this topic."

I would have to see the newer ones in action. Mini-split systems might really be better, but the units I have seen hanging on the wall are not the most attractive things. It is, after all, a matter of choice. I choose to avoid heat pumps if I have a viable, cost effective alternative such as the natural gas heat and air conditioning package unit that we have. It might not be the most efficient, but it has been reliable except when the power has gone out. That is, however, rare and we do have the RPod to use if there is a longer outage.
StephenH
Happy is the man that findeth wisdom,...

ouR escaPOD mods
Former RPod 179
Current Cherokee Grey Wolf 24 JS
Back to Top
mjlrpod View Drop Down
Senior Member
Senior Member
Avatar

Joined: 27 Sep 2016
Location: Massachusetts
Online Status: Offline
Posts: 1214 		Post Options Post Options   Quote mjlrpod Quote  Post ReplyReply Direct Link To This Post Posted: 30 Oct 2022 at 3:39pm
I use a pellet stove. I cant say enough good things about it. Mine is a Harmon fireplace insert. I never use the boiler in the house, unless I choose too. I burn nothing but douglass fir pellets and can go 2 weeks or more in the absolute dead of winter without emptying ash ashpan. Really good system, except you need to buy pellets. I don't have any neighbors saying " hey a pallet of pellets fell in my yard, wanna come get it?" 
2017.5 Rp-172
2020 R-pod 195
2015 Frontier sv 4.0L 6cyl
I'll be rpodding
Back to Top
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290 		Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Posted: 30 Oct 2022 at 12:15pm
Originally posted by offgrid

Originally posted by StephenH

Part of the problem is the frost level. I saw two types. One used a run that was bigger, buried so that the ground loop was wide and shallow. The other was deep and the loops were installed vertically. Those would likely work in the really cold climates. The need to dig deep for a horizontal loop would likely not be too much more than drilling for a vertical loop.

What makes the air source so much less attractive is that when the heat just isn't there to extract, pure resistance electric elements are used. This is why my heating bills were very high. I admit the newer, high efficiency ones would be better and not use resistance heat as much, but that is not to say that there are not situations where they would not be used. Also, the air source ones need to run a defrost cycle periodically to make sure the outside coil does not get an ice build-up. If one lives in an area where there is a lot of snow, then one would need to have a way to keep the outside unit sheltered from snow build-up so the snow does not block the airflow. Ground loops don't have those problems. 

In some areas, solar modules would work great. In others, subject to many days of overcast skies, solar might not provide much assistance. I grew up in western New York. We had plenty of cold, cloudy, snowy (lake effect snow belt) days where solar would not have contributed much. If these days were followed by sunny ones, then one would have had to go and clear the snow off the panels for them to do much good.

I would say that if the situation is such that air source would work, then go for it. If not, then ground source is a great option. It is also good for those scorcher days when the air temperature is hot since the heat pump would have a much cooler place to dump the heat from the house. That is the other half of the heating/cooling problem which has not been addressed so far in this topic.

Another option is a water-jacket wood burning furnace. It could be teamed with different backup sources for heating water to circulate in a hydronic heating system (radiators) or a water to air heat exchanger for a forced air system. I know people who have had such systems. Some use indoor water jacket wood burning stoves. Others have a system that is outdoors and so keeps the indoor air clean and free from smoke and the possibility of CO poisoning.


StephenH, you keep referring to the performance of the older air source technology. With all due respect,  please get an update. Look for example at the Fujitsu EXLTH mini splits. They operate efficiently down to around -15F. You and I will never ever see temps anywhere near that low. The ASHRAE 99% heating design temp where I live is 12F. That is the number HVAC professionals use to design heating system capacity. Yours is more like 20F.  There is always heat to extract, as long as the temp is above absolute zero, which cannot be reached anyhow ( 3rd law of thermodynamics). So the heat content of air at -15F is still 97% of air at 35F (if I did the math right). 

I just finished modelling the thermal performance of my house and an upgrade to my HVAC system, prompted by the tax benefits for new heat pumps, solar, energy storage, heat pump water heaters, and insulation in the IRA. Four little Fujitsus will heat my whole house. Compare that to the not so old Goodman central heat pump that was here when I bought the place 3 years ago, which craps out at around 35F, just as you say. 

There are modern efficient central heat pumps becoming available as well, but I think I'll go with mini splits personally. I like them because they are zoned, extremely quiet, and accommodate DIY installs. I've installed them before.  Outside North America residential central air is very unusual, everyone goes with mini splits. For good reason. 

I do plan to retain my central ductwork system and air handler though, so I can potentially install a wood based hydronic system as you are suggesting. You can no longer purchase a glass front wood stove with a water jacket (aka a water stove) in the US. These are very common in Europe. I found one on Craigslist a couple years ago and have it sitting in my barn. It combines the benefits of hydronic heating with fire  viewing (which we all seem to enjoy). I would like to connect it with a water thermal storage system and a water to air heat exchanger in my air handler. The storage system will allow on demand heating without needing to continuously fire the stove. Lots of technical and safety details to work out though  and insulated storage tanks aren't cheap...

As for solar, you would be right if we are talking about an off grid PV system, but no one does that if they don't have to due to lack of grid access. Residential solar nearly everywhere except Hawaii is net metered with an annual true up,  meaning that you are credited for summer production in the winter. 100% credit. So no need to match solar production with heat load. Forget pushing snow off the array.... The small difference in electricity consumption between a geothermal heat pump and a high efficiency air source heat pump system can be met far more inexpensively with a few additional PV modules. Personally, if I was in the geothermal heat pump business I would be thinking about how to transition out and into  solar and mini split contracting. 
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
Back to Top
offgrid View Drop Down
Senior Member
Senior Member


Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290 		Post Options Post Options   Quote offgrid Quote  Post ReplyReply Direct Link To This Post Posted: 30 Oct 2022 at 12:09pm
Originally posted by StephenH

Part of the problem is the frost level. I saw two types. One used a run that was bigger, buried so that the ground loop was wide and shallow. The other was deep and the loops were installed vertically. Those would likely work in the really cold climates. The need to dig deep for a horizontal loop would likely not be too much more than drilling for a vertical loop.

What makes the air source so much less attractive is that when the heat just isn't there to extract, pure resistance electric elements are used. This is why my heating bills were very high. I admit the newer, high efficiency ones would be better and not use resistance heat as much, but that is not to say that there are not situations where they would not be used. Also, the air source ones need to run a defrost cycle periodically to make sure the outside coil does not get an ice build-up. If one lives in an area where there is a lot of snow, then one would need to have a way to keep the outside unit sheltered from snow build-up so the snow does not block the airflow. Ground loops don't have those problems. 

In some areas, solar modules would work great. In others, subject to many days of overcast skies, solar might not provide much assistance. I grew up in western New York. We had plenty of cold, cloudy, snowy (lake effect snow belt) days where solar would not have contributed much. If these days were followed by sunny ones, then one would have had to go and clear the snow off the panels for them to do much good.

I would say that if the situation is such that air source would work, then go for it. If not, then ground source is a great option. It is also good for those scorcher days when the air temperature is hot since the heat pump would have a much cooler place to dump the heat from the house. That is the other half of the heating/cooling problem which has not been addressed so far in this topic.

Another option is a water-jacket wood burning furnace. It could be teamed with different backup sources for heating water to circulate in a hydronic heating system (radiators) or a water to air heat exchanger for a forced air system. I know people who have had such systems. Some use indoor water jacket wood burning stoves. Others have a system that is outdoors and so keeps the indoor air clean and free from smoke and the possibility of CO poisoning.


StephenH, you keep referring to the performance of the older air source technology. With all due respect,  please get an update. Look for example at the Fujitsu EXLTH mini splits. They operate efficiently down to around -15F. You and I will never ever see temps anywhere near that low. The ASHRAE 99% heating design temp where I live is 12F. That is the number HVAC professionals use to design heating system capacity. Yours is more like 20F. 

I just finished modelling the thermal performance of my house and an upgrade to my HVAC system, prompted by the tax benefits for new heat pumps, solar, energy storage, heat pump water heaters, and insulation in the IRA. A couple of those Fujitsus will heat my whole house. Compare that to the not so old Goodman central heat pump that was here when I bought the place 3 years ago, which craps out at around 35F, just as you say. 

There are modern efficient central heat pumps becoming available as well, but I think I'll go with mini splits personally. I like them because they are zoned, extremely quiet, and accommodate DIY installs. I've installed them before.  Outside North America residential central air is very unusual, everyone goes with mini splits. For good reason. 

I do plan to retain my central ductwork system and air handler though, so I can potentially install a wood based hydronic system as you are suggesting. You can no longer purchase a glass front wood stove with a water jacket (aka a water stove) in the US. These are very common in Europe. I found one on Craigslist a couple years ago and have it sitting in my barn. It combines the benefits of hydronic heating with fire  viewing (which we all seem to enjoy). I would like to connect it with a water thermal storage system and a water to air heat exchanger in my air handler. The storage system will allow on demand heating without needing to continuously fire the stove. Lots of technical and safety details to work out though  and insulated storage tanks aren't cheap...

As for solar, you would be right if we are talking about an off grid PV system, but no one does that if they don't have to due to lack of grid access. Residential solar nearly everywhere except Hawaii is net metered with an annual true up,  meaning that you are credited for summer production in the winter. 100% credit. So no need to match solar production with heat load. Forget pushing snow off the array.... The small difference in electricity consumption between a geothermal heat pump and a high efficiency air source heat pump system can be met far more inexpensively with a few additional PV modules. Personally, if I was in the geothermal heat pump business I would be thinking about how to transition out and into  solar and mini split contracting. 
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
Back to Top
 Post Reply Post Reply Page  123 4>

Forum Jump Forum Permissions View Drop Down

Bulletin Board Software by Web Wiz Forums® version 9.64
Copyright ©2001-2009 Web Wiz