This is interesting. I've been playing in the fireplace for the past day or so. I've had some fascinating results. Coal is cool stuff. The bag of nut coal I bought from Tractor Supply was water logged. I figured I'd just work with what I had, instead of drying it out first. What I ended up with was a 1 gallon pail's worth burn for 8 hours, and after I went to bed the stuff finally went out. When I got up this morning, the pile had only lost about 1/2 it's volume. I piled another gallon or so on, and it got it re-lit. With a bellows, I probably could have gotten the leftovers going again. It was still warm. Here's the really interesting thing: if you put anything on top of the pile, it burns much hotter. I put a couple of 2X6 scraps on top, and immediately got a major hotspot. It would seem the coal requires something on top to concentrate the heat. I suppose a bigger pile would work, but I did not want to push it. This is an open fireplace, so there would be no way to control it if it really got going. Overall, I can see why folks don't use coal in their fireplaces. This was a $6 sack and it produced a long lasting fire, but no visible flame and really minimal heat for all the effort. This was nut coal-- pieces were less than 2 inches across. It was waterlogged, but that seemed to not be a huge problem. It was on a raised grate with good airflow underneath. If I was going to use it in a fireplace, I'd do a few things: 1) Find a V-shaped grate that concentrated the pile better. 2) Find a way to shake the pile and get the ash off 3) Find a way to control airflow and thereby control the burn. . . . in short, that's what a coal stove or furnace does. I can see this being duplicated in a fireplace, but that is not going to happen this weekend.
yikes.. that seems spendy, I get 50Kg premium delivered for about £16 which means most pieces are at least 4-6" with quite a few 8-10" chunks. Last me about a week this time of year & thats burning 24/7 as we don't have any other heating for our house. I dont think it being wet is that much of an issue as it dosent really soak in like with peat or wood.. so if you get a lil more of a starter fire (or a few more firelighters) it burns off the water quick enough. & If you have a coal fire going, adding wet coal on top just slows down the burn time for a bit
Tractor Supply's $6/bag coal was just a matter of convenience. I'm certain I can get a good rate buying bulk locally. In fact, I just got confirmation that there's a place selling retail that I pass every day going to work. BTW: I just threw another gallon or so on top of what was there. It had been burning since before 0700, and it was starting to wane. This was a bigger pile than yesterday's. Geothermal? I have not thought much about it yet. I'll have a pond close by , but I figure I'll probably get a company in to dig . I'm open to ideas.
Lots of articles about burying plastic pipe( several hundred feet) several feet underground to take advantage of the constant temps at depth. Warms during the winter and cools in the summer. I will look around and see if I can find those for you.
Cool. Many thanks. I've got the land, so burying pipe in the back yard is. . . well, there's 200 acres there. I'm sure I can find the space. I had not thought of this as a DIY project, but now that you mention it, maybe I could give it a whirl. Update on the coal. It's fascinating stuff. I know what I'm experiencing is not what my grandpa had. The pile is just slowly smouldering-- lasts a long time, but very little heat coming out. This may be the difference between the nut that I'm using and the big chunks I remember grandpa using. The current pile has been going all afternoon.
Perhaps a bit picky, but that is not true geothermal, that is "earth sourced". Not too common so far as I know, but those few systems I had some knowledge of in the past did work well as a more or less constant temp feed to a reversible heat pump arrangement. If there is a restriction on area, the same approach can be taken with vertical installations in wells.
I got up this morning and looked at what was left. Overnight, the pile had turned to white clunkers in the middle and left the edges of the pile black. It was still warm, and I probably gotten it fired up again if I'd worked at it. The deficiencies I'm seeing are pretty significant. 1) Low heat-- this stuff never did fill the room with heat. At its hottest, it was cooler than a wood fire left to go to coals. 2) Hard to light. 3) A lot of waste. I daresay I'm done to a 1/4 of the original mass, but the clunkers are piling up.
That dosent sound like true coal... The stuff we use can get freaking hot. especially if you open the fire up for a few minutes to get it going.. & we dont get that much ash from it, less than wood & Much less than peat. As for chunks left, piling them together if there still burning & opening up the fire a few minutes or adding more coal & opening up to get going, usually results in most leftover chunks burning up
That's one of the issues with coal. Different parts of the same coal seam can yield entirely different burn properties...YMMV widely.
I'll admit, these results were not what I expected, and not what I remember. I remember a robust fire that burned ridiculously hot. Gramps only made these fires for two reasons: 1) When it was super cold outside. He'd use this as a supplement for heating the living room that was one floor above. 2) When the whole family used to go downstairs to party in the winter. He would light one of these coal fires to knock off the chill and dampness in a hurry. What I had going in the firebasket this weekend was rather anemic.
