[Peleg]

link
Nice presentation on dimming. The time rate of effect of GHGe's is longer than aerosols for the most part. What this could mean (a little food for the doomers here) is that a hard peak oil scenario produces a deep depression which drastically cuts pollution inputs for a few years allowing the aerosol satefy net to waken and severe climate change to raise it's ugly head.

On the other hand, power de-evolution mpobing back to coal and such could create lower quality air but actually mitigate climate change on a longer time frame. The problem is that eventually the very potent effects of GHGe's has to overrun the safety net. Some future generation will feel the pain of any attempt we make to deal with climate other thatn cutting back on emissions. Yet another wrinkle in the connected world in which we live.

[TheDude]

Global warming exaggerated, insufficient oil , natural gas and coal from ASPO President Kjell Aleklett. Global Dimming throws a real wrench in the works. I started a thread on Global dimming and the airlines as well.

You can see the NOVA program on Google Video, too.

[Battle_Scarred_Galactico]

Coal use will go up drastically no doubt about that. Also oil shale will happily sit in the ground until the political landscape changes and nations with it will get to burning it directly.

[Tanada]

People in tropical and even sub-tropical areas should have no need for heated living spaces. How many people does that constitute? I believe newer woodstoves and pellet stoves are very efficient. This will be the only way to heat up here in the northwoods after natural gas peaks or prices spike. Maybe we'll become a nation of migratory humans. Spending summers in the north growing crops and winters in Mexico and South Texas tending the winter crops.

I think a return to coal, either directly or through the use of electric heat pumps and baseboard heat is far more likely than people migrating a thousand miles in a world with liquid fossile fuel shortages

[Quinny]

Efficiency helps. Rocket stoves burn most of the harmful emissions.

[MarkJ]

Wood Burning on a very large scale would be a nightmare.

This chart describes the relative emissions of fine particles (PM 2.5) from various fuels burned in fireplaces, wood stoves, and furnaces:
Fireplace: 28 pounds per million Btu heat output
Uncertified Wood Stove: 4.6 pounds per million Btu heat output
EPA Certified Wood Stove: 1.4 pounds per million Btu heat output
Pellet Stove: 0.49 pounds per million Btu heat output
Oil Furnace: 0.013 pounds per million Btu heat output
Gas Furnace: 0.0083 pounds per million Btu heat output
Fireplaces and woodstoves, and even special equipment such as wood pellet combustors and EPA Phase II Certified woodstoves, produce orders of magnitude more particulate matter than well-tuned oil or gas devices producing equivalent heat. Moreover, woodstoves routinely produce several times more air pollutants than original design values simply because of improper operation (including their misuse as incinerators for residential refuse), maintenance, and normal equipment degradation with use.

Besides burning much cleaner, my oil and gas fired boilers only fire for very short periods of time to satisfy space heating and domestic hot water demand.

Many of our customers with wood stoves, wood boilers, fireplaces and outdoor wood boilers burn all sorts of garbage in them. (plastic, styrofoam, papers, oil soaked rags, cardboard and construction debris including pressure treated lumber, boards coated with lead paint, sealants, adhesives

Wood and pellets are very inconsistent in quality, moisture content, BTU Value, so it's difficult to maintain consistent combustion. When we tune propane, natural gas and oil fired equipment with electronic combustion test equipment, it generally stays in tune.

We service and tune the majority of our customer's oil fired equipment on an annual basis, so it's running at peak efficiency. Most of the local fire related emergency response calls are from wood stove related fires. Most of the CO related calls are from gas fired equipment since people generally don't have it inspected, or tuned annually.

Much of the installed base of wood burning equipment was self-installed and/or installed by non professionals.

[vision-master]

Around here you gotta run a class "A" chimmey all the way down to the stove and I think 4' extended over the roof peak. Also, some of the new wood stoves burn pretty efficent if'n ya know how to fire em. AND twice a year chimmey cleaning is in order at minimum.

[MarkJ]

The areas with the most wood burning equipment (areas without natural gas - villages, outer suburbs, rural areas, exburbs) have the least amount of additional local venting regulations and/or little enforcement of venting regulations. These areas also have the highest amount of older low efficiency wood burning equipment.

Most boilers and furnaces are installed, maintained and serviced by licensed or qualified professionals, but many biomass burning stoves, all-fuel chimneys, all-fuel liners, side-wall vents are installed, maintained and repaired by homeowners, friends, relatives, neighbors, handymen etc without permits, inspections and insurance since free-standing stoves are so simple to install.

We see a lot of sidewall terminations under or too close to windows, doors, vents, air intakes, under decks, lower than snow lines etc. Many homeowners also install wood stove vent pipes in existing chimneys used by existing furnaces, boilers or water heaters. Many roof terminations are too short and/or in bad locations as well. Many of the plumbing vent terminations are too low for the snow depth as well, especially on low pitch roofs.

Traditional unlined chimneys cause problems with some modern high efficiency oil fired boilers as well. Ultra Low stack temperatures and short run cycles can cause major condensation and draft issues. Some units have a wicked chimney roar in unlined chimneys as well.

Many chimneys worked well with always-on wood fires or inefficient furnaces, boilers and water heaters with higher stack temperatures.

[dohboi]

"Many of our customers with wood stoves, wood boilers, fireplaces and outdoor wood boilers burn all sorts of garbage in them. (plastic, styrofoam, papers, oil soaked rags, cardboard and construction debris including pressure treated lumber, boards coated with lead paint, sealants, adhesives"

Good point, but contamination is also a problem with many larger, industrial wood burners. The market controls what they burn, and however virtuous they say they are going to be at the outset about just burning clean wood, when prices get too high they inevitably turn to various scrap of the sorts you mentioned.

I do wonder about high efficiency stoves if operated properly and fueled with clean wood. Even with these, would the particulates become too hazardous if they are widely adopted. In Minneapolis and other northern cities, this will soon become a life-and-death issue.

Of course, insulation and conservation (not heating rooms you aren't in, not heating hotter than you need, high occupancy small houses...) must be the central priorities. I see a roll for wood, but it has many real and potential problems both on the supply side and on the pollution side.

[Revi]

I don't think we'll be able to heat a lot of the northern US with wood, and we are in a well wooded place. It only grows about a half a cord per acre per year. That means every family needs at least 2 acres just to keep a tiny area warm. There's no way that there is 2 acres per household even here in New England.

It's getting hard to find good hardwood even now.

There's no way we'll be able to switch to wood as heat.

[aflatoxin]

I've done EPA emissions tests on gas, oil, coal, and wood fired boilers and furnaces. Wood, hands down, is the dirtiest fuel.

There are a lot of metals and other bad stuff in wood that comes out of the stack. Scrubbers do help, though. Most of the ones I've seen don't work very well.

[Frank]

How do metals get into wood? Which metals? Are you talking industrial boilers which might be burning old pressure treated wood (arsenic)?

Inefficient stoves/boilers (non-gassifying) or burning lousy wood can certainly increase particulates and be very dirty. Maine has just tightened up regulations on outdoor wood boilers, most of which are just fireboxes surrounded by water. Premium pellets are <1% ash and pretty consistent. There's a shortage of solid-fuels licenses here in Maine. There's other considerations with switching to wood too quickly ex. impacting the paper industry. See http://maine.gov/doc/initiatives/wood_t ... force.html for info on Maine's program.

[dohboi]

"There's other considerations with switching to wood too quickly ex. impacting the paper industry."

uh oh...Peak Toilet Paper!!??

[FoolYap]

I don't think we'll be able to heat a lot of the northern US with wood, and we are in a well wooded place. It only grows about a half a cord per acre per year. That means every family needs at least 2 acres just to keep a tiny area warm. There's no way that there is 2 acres per household even here in New England.

It's getting hard to find good hardwood even now.

There's no way we'll be able to switch to wood as heat.

All true, but I think there's still a lot of houses around here that burn wood, but that have very inefficient means of doing so (old woodstoves, or even traditional fireplaces), and that have really poor (or no) insulation in the attic and walls, old drafty windows, etc. So we could probably reduce the amount of wood that would otherwise be burned per household.

OTOH, making older houses tighter means burning wood (or anything creating CO and CO2) is more dangerous without active (powered) ventilation.

Tradeoffs I guess.

--Steve

[aflatoxin]

How do metals get into wood? Which metals? Are you talking industrial boilers which might be burning old pressure treated wood (arsenic)?

Inefficient stoves/boilers (non-gassifying) or burning lousy wood can certainly increase particulates and be very dirty. Maine has just tightened up regulations on outdoor wood boilers, most of which are just fireboxes surrounded by water. Premium pellets are <1% ash and pretty consistent. There's a shortage of solid-fuels licenses here in Maine. There's other considerations with switching to wood too quickly ex. impacting the paper industry. See http://maine.gov/doc/initiatives/wood_t ... force.html for info on Maine's program.

The trees take up the metals in the soil that they are growing in. This includes Iron, Manganese, Copper, Zinc, and all of the others like Lead, Chromium, etc. I've been told that they tend to concentrate in the bark. I've seen Method 5 filters from testing at sawmill boilers come out shiny grey, looking like a lead brick, almost car bumper color. When they look like this, they always fail the test. The metals vaporize in the flame, and condense out as they go through the watertubes and the stack.

The gassifying stoves are better, but even then there are a lot of organics in wood smoke that form deposits in the stack, and condense out of the plume in the atmosphere. Wood, being a non-uniform material is hard to really thoroughly combust.

There are also other gasses like HCl that are in wood smoke, plus the usual Criteria Pollutants like NOx, SO2, CO, and Particulate Matter.

BTW, I heated my house exclusively with wood for about 15 years.

[rattleshirt]

It all comes back around to there being to many of us in the world. I don't remember whose line it was but I think it is about right, " Doom is good, Doom is wise, Bring on the die-off already." As for me I will survive as best I can and except death when it finds me.

[rattleshirt]

accept, I mean.

[Frank]

The trees take up the metals in the soil that they are growing in. This includes Iron, Manganese, Copper, Zinc, and all of the others like Lead, Chromium, etc. I've been told that they tend to concentrate in the bark. I've seen Method 5 filters from testing at sawmill boilers come out shiny grey, looking like a lead brick, almost car bumper color. When they look like this, they always fail the test. The metals vaporize in the flame, and condense out as they go through the watertubes and the stack.

Well, that is certainly something I didn't consider. I wonder if paper mills and biomass boilers use scrubbers with an acidic spray?

[aflatoxin]

Depending on the age of the unit, there are several types of scrubbers and filtering devices used. The newer stuff is certainly better than the old. None of these systems offer 100% control, but some hit four nines (99.99%)

The scrubber liquor that I've seen is usually water. Of course, after a period of use, everything scrubbed out is dissolved/in suspension. I'm not sure about the pH of this liquid, but if I had to guess, I'd say that they try to keep it neutral/basic for corrosion reasons, and the higher pH helps with the acidic gasses like SO2 that are expensive to emit.

[Ferretlover]

CNN World News last night: The world map showing the spreading path of this brown cloud showed it heading for California:

U.N. Reports Pollution Threat in Asia

BEIJING — A noxious cocktail of soot, smog and toxic chemicals is blotting out the sun, fouling the lungs of millions of people and altering weather patterns in large parts of Asia, according to a report released Thursday by the United Nations.
The byproduct of automobiles, slash-and-burn agriculture, cooking on dung or wood fires and coal-fired power plants, these plumes rise over southern Africa, the Amazon basin and North America. But they are most pronounced in Asia, where so-called atmospheric brown clouds are dramatically reducing sunlight in many Chinese cities and leading to decreased crop yields in swaths of rural India, say a team of more than a dozen scientists who have been studying the problem since 2002.
The brownish haze, sometimes in a layer more than a mile thick and clearly visible from airplanes, stretches from the Arabian Peninsula to the Yellow Sea. In the spring, it sweeps past North and South Korea and Japan. Sometimes the cloud drifts as far east as California. …

NYTimes

UN: Clouds of pollution threaten glaciers, health By TINI TRAN and JOHN HEILPRIN

A dirty brown haze sometimes more than a mile thick is darkening skies not only over vast areas of Asia, but also in the Middle East, southern Africa and the Amazon Basin, changing weather patterns around the world and threatening health and food supplies, the U.N. reported Thursday.
The huge smog-like plumes, caused mainly by the burning of fossil fuels and firewood, are known as "atmospheric brown clouds."
When mixed with emissions of carbon dioxide and other gases blamed for warming the earth's atmosphere like a greenhouse, they are the newest threat to the global environment, according to a report commissioned by the U.N. Environment Program. …

Associated Press