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Hazell B
19th December 2006, 20:30
..... and warm :mark:

Now we've gone over to just a log burner to heat the house, I've had to get out my calculator and work out how much wood we need to burn each winter to stay warm. It's shocking reading.

To use the burner to heat a small house takes about 400 YEARS of wood growth each winter - and that's a very conservative estimate.

That's forty, ten year old trees or twenty, twenty year old ones. One four hundred year old tree wouldn't do the job, but as even I don't expect to live long enough to grow one, it doesn't matter :p :

To be carbon neutral for just my heating, I need approx 160 square yards of land each year, for ten years, just to produce the wood. I also need extra trees to cover the carbon from trips to the land to collect the wood, room to store it a year before it's dry enough to burn, yet more trees planted to cover emissions from cutting tools being made and/or used and fertilizer production.

In short, by my pen and paper calculations, to make a carbon neutral heating system in the UK each house will need a minimum of two acres of woodland, planted a the person's birth and maintained thoughout their life.

I think we're going to need a bigger country if government targets are to be met :mark:

Eki
19th December 2006, 22:23
Just buy a thicker sweater.

Dave B
20th December 2006, 00:06
There's a wood near Brands Hatch which grows quite quickly... ;)

CarlMetro
20th December 2006, 00:41
I'm left wondering if she included the paper she used whilst doing the calculations in the calculations :p :

Hazell B
21st December 2006, 19:59
There's a wood near Brands Hatch which grows quite quickly... ;)

Yes, it's warmer darf sarf. And of course the stupid are more easily fooled down there, too :laugh:

Thanks for pointing that out Carl. I'll have to plant another ruddy rowan, now :(

jim mcglinchey
21st December 2006, 20:07
Ms B, I think you're confusing being green with saving yourself money. OK you might be able to get the wood free, but burning it isnt very green. Were in our house 13 years and this year for the first time, Ive lit a log fire because oil is so bloody dear.

Hazell B
21st December 2006, 20:21
Burning is carbon neutral. No other normal heating is. Can't get much greener ;)

The tree's growth and it's death each take in/give off exactly the same chemicals (well, important ones like carbon anyway) and burning in a tree's early years allows faster turnover of carbon (they grow slower as they age).

Oil, coal, etc took more wood to make than they appear, so to heat with them uses far more years of growth, plus they've already given off the majority their carbon as they decay and alter. At least, that's what I'm told, but I'm no oil and coal-ologist :p :

And the nasty part is it isn't saving me money at all. Farm land isn't exactly free you know. I hear they stopped making it some time back :p :

bowler
22nd December 2006, 04:40
and I thought this was about Kermit the Frog's song

"it's not easy being green"

which makes more sense than carbon credits.........

cosmicpanda
22nd December 2006, 05:47
Burning is carbon neutral. No other normal heating is. Can't get much greener ;)

well, there's the sun.

Daniel
22nd December 2006, 10:16
Burning is carbon neutral. No other normal heating is. Can't get much greener

The tree's growth and it's death each take in/give off exactly the same chemicals (well, important ones like carbon anyway) and burning in a tree's early years allows faster turnover of carbon (they grow slower as they age).

Oil, coal, etc took more wood to make than they appear, so to heat with them uses far more years of growth, plus they've already given off the majority their carbon as they decay and alter. At least, that's what I'm told, but I'm no oil and coal-ologist :p :

And the nasty part is it isn't saving me money at all. Farm land isn't exactly free you know. I hear they stopped making it some time back :p :

I don't get how burning is carbon neutral :confused:

Ok there you've got carbon just standing around in tree form so you cut it down and burn it up and release the carbon that was in the form of a tree. Net result + carbon to the atmosphere. Now if you've planted the tree yourself and then cut it down it is but to say it's carbon neutral is a bit misleading because everything is carbon neutral till you burn it ;)

Plus oil, coal and gas if they do give off carbon in the process of being formed do it regardless of whether you use them or not so counting any carbon given off while they're forming is unfair.

BTW is your fire one of the slow combustion ones? They give out a lot less smoke and are a lot more efficient than fast burning ones.

I love this little gem.

http://www.sniffpetrol.com/latenews0611_01.jpg

Hazell B
22nd December 2006, 20:01
well, there's the sun.

I'm English. I have no idea who the sun is or where he lives :mark: :p :

Daniel, the tree's growth absorbs carbon, then as it either dies and rots naturally, or is burned, it releases the exact same carbon back. Human bodies, stubble in corn fields, a mown lawn, etc all do the same. I mislead nobody, it is fact ;)

The point of coal, oil and so on is that they've given off their natural carbon as they've decayed, but become something else in the mean time that again gives off carbon. I don't understand it either, but as the local coal fired energy plant has recently been awarded something like £10m be get more green and give off less carbon, it's fact. Kneeslider would explain it best.

It's either a slow or fast burner thanks to some air vent thingies all over it's front and back. God alone knows how they work - I just open the door when I want more heat :p :

jim mcglinchey
22nd December 2006, 23:41
Now Im no professor of organic chemistry either but surely you can lump wood in with hydrocarbon fuels such as coal and oil, peat briquettes etc which when burnt give off alot of their carbon content as CO2.

CarlMetro
23rd December 2006, 04:45
and I thought this was about Kermit the Frog's song

Which was what sprung to my mind when I read the title :D

Kneeslider
23rd December 2006, 11:46
The point of coal, oil and so on is that they've given off their natural carbon as they've decayed, but become something else in the mean time that again gives off carbon. I don't understand it either, but as the local coal fired energy plant has recently been awarded something like £10m be get more green and give off less carbon, it's fact. Kneeslider would explain it best.



Heehe, thanks Hazel! Looks like I can't get out of it now!

As you say, when a tree, or any other type of plant for that matter grows, it takes in CO2, and uses light and water through the process of Photosynthesis, and turns these building blocks into long chain hydrocarbons. When we burn the tree, we are just reversing the process, by adding oxygen we get heat out, plus CO2 and water (as water vapour, or steam) People argue that this process is carbon neutral, because we have the same quantity of carbon taken out of the air by the growth of the tree as is put back when it is burnt. Which is all fine and dandy.

Or is it?

Using that very same rationale, another tree, this time grew millions of years ago, it took CO2 out of the atmosphere, and then the tree died, decayed, and over several thousands of years became compressed and turned into coal. Some time later, this lump of coal is then burned, which releases the CO2 locked up in it. This process is exactly the same as the one above.

The crucial point is that in the atmosphere, we now have rising levels of CO2, because all of the carbon locked up in forests, and fossil fuels alike is being burned and released into the atmosphere, so the ammount of time that you can take CO2 out of the atmospheric system for is the critical thing. To be properly carbon neutral, you would need to work out the rate that you are producing CO2 (which according to current figures, is about 10 tonnes per household in the UK per year, CO2 has an relative atomic mass of 44, ie one mole of CO2 weighs 44 grammes, equating to 5,100 cubic metres of CO2) and work out how many trees you need to have per household to take in 5,100 cubic metres of CO2 every year. Now that is properly carbon neutral.

Might as well take this opportunity to talk about so called 'Green' electricity tarriffs too. Does anyone want to have a guess about how much 'green' electricity you actually get when you sign up to one of these tariffs? :p :

cosmicpanda
23rd December 2006, 12:12
I'm English. I have no idea who the sun is or where he lives :mark: :p :

can't you burn it? I hear it's not a well respected publication.

Daniel
23rd December 2006, 12:58
Heehe, thanks Hazel! Looks like I can't get out of it now!

As you say, when a tree, or any other type of plant for that matter grows, it takes in CO2, and uses light and water through the process of Photosynthesis, and turns these building blocks into long chain hydrocarbons. When we burn the tree, we are just reversing the process, by adding oxygen we get heat out, plus CO2 and water (as water vapour, or steam) People argue that this process is carbon neutral, because we have the same quantity of carbon taken out of the air by the growth of the tree as is put back when it is burnt. Which is all fine and dandy.

Or is it?

Using that very same rationale, another tree, this time grew millions of years ago, it took CO2 out of the atmosphere, and then the tree died, decayed, and over several thousands of years became compressed and turned into coal. Some time later, this lump of coal is then burned, which releases the CO2 locked up in it. This process is exactly the same as the one above.

The crucial point is that in the atmosphere, we now have rising levels of CO2, because all of the carbon locked up in forests, and fossil fuels alike is being burned and released into the atmosphere, so the ammount of time that you can take CO2 out of the atmospheric system for is the critical thing. To be properly carbon neutral, you would need to work out the rate that you are producing CO2 (which according to current figures, is about 10 tonnes per household in the UK per year, CO2 has an relative atomic mass of 44, ie one mole of CO2 weighs 44 grammes, equating to 5,100 cubic metres of CO2) and work out how many trees you need to have per household to take in 5,100 cubic metres of CO2 every year. Now that is properly carbon neutral.

Might as well take this opportunity to talk about so called 'Green' electricity tarriffs too. Does anyone want to have a guess about how much 'green' electricity you actually get when you sign up to one of these tariffs? :p :
yes. I was going to reply in the same manner to Hazell regarding her "carbon neutral" wood burner :laugh: If you used that logic everything is carbon neutral. But it isn't. Carbon neutral is more to do as you say with releasing carbon into the atmosphere.

Hazell B
23rd December 2006, 18:25
Daniel, a few days ago you were posting about how we should try and be greener, now you're taking the pee out of somebody who's trying to be just that. Make your mind up, eh?

If I grow my own wood and burn it, I'm greener than if you buy coal, electricity or gas to heat your home. Fact. I'm absorbing as well as pushing out carbon. Unless you heat with solar (not very efficient yet - I know because I already use it) or wind, you're in no position to take the pee out of our method ;)

By the way, I grow more than I burn. Selling trees for a living sort of does that :laugh:

COD
23rd December 2006, 20:29
well, there's the sun.

They are in UK, they rarely se that phenomenon :D

If they could use rain somehow, it would be more realistic :laugh:

Daniel
23rd December 2006, 22:00
Daniel, a few days ago you were posting about how we should try and be greener, now you're taking the pee out of somebody who's trying to be just that. Make your mind up, eh?

Trying being the operative word.

My point was that your statement was misleading which it is. When a piece of coal is burnt it gives out the same amount of carbon as it took in when it was part of a tree so as pointed out by kneeslider it's also carbon neutral in your books. Same with oil, gas and any fossil fuels.

Being truly carbon neutral is releasing CO2 into the atmosphere and pulling it back in at the same rate. Not as you suggest getting a tree which pulled in CO2 and then burning it to release the CO2 which is the same process but in reverse.

Anyone in this country who tries to use solar power to heat their water is hopeful at best. Caroline and I went to the centre for alternative technology a few months ago and on a slightly sunny day the water was pitifully tepid at best

What you people need if you want to even start to think about heating water is one of these

http://happy.emu.id.au/neilp/solar/solhart2.jpg

Far better than a tiny little useless things they sell here.......

My parents have one on their roof in Perth and I'd say about 85% of their hot water is free. The panels are far bigger (about 1m x 2m for each individual panel and you usually have 2) and the tank is reflective so it reflects extra sunlight onto the panels and the heating system works thusly. http://www.solahart.com/default.asp?V_DOC_ID=748

Far better than the stuff I've seen for sale here so far.

Could go on but can't be bothered ;)

cosmicpanda
24th December 2006, 10:36
the tank is reflective so it reflects extra sunlight onto the panels


how does it manage that? it looks like it would reflect the light in all directions, so that only a little bit more light would hit the panels. And when the sun's at the wrong angle, wouldn't the tank shade the panels, as well?

jim mcglinchey
24th December 2006, 11:24
Shirley the tank should be matt blacked to absorb as much radiation as possible?

Daniel
24th December 2006, 12:21
how does it manage that? it looks like it would reflect the light in all directions, so that only a little bit more light would hit the panels. And when the sun's at the wrong angle, wouldn't the tank shade the panels, as well?

Well what you do is if you're in the Southern Hemisphere you put the panel on a north facing roof and the panels are NEVER shaded by the tank because the sun is never directly overhead unless you live in the tropics.


Shirley the tank should be matt blacked to absorb as much radiation as possible?

The panels are black ;) The glass merely insulates them so they don't give off all their heat back to the atmosphere.

Kneeslider
24th December 2006, 13:10
I think that in my previous post I might have given the impression that I am belittling the efforts of those who are trying to live a 'greener' lifestyle, far from it infact, I use a wood burner coupled into my central heating system to provide additional heat and hot water, and to reduce my fuel bills, the logs come from the garden anyway! When I had a diesel car, I used biodiesel to fill it up when I could. (incidentally, the fuel station at Snaith which used to provide biofuel has since closed down, it used to sell biodiesel at 10p/litre below the market value) Fossil fuels are a finite resource, and in an ideal world, should only be used when there isn't another practical alternative.

I was going to highlight the dubious delights of the green electricity tarriffs which are being touted around by suppliers, but I think that newsnight's eccellent Ethical Man series got there before me.

Try this link out, it's a little long winded, but worth it. I would advise that you think very carefully before contemplating using a green energy tarriff!

http://www.bbc.co.uk/blogs/newsnight/2006/12/i_am_not_a_transsexual_i_just_want_to_talk_green_e _1.html