Wood pellet fired boiler to heat new school

[SwampDonkey]

The city of Fredericton, NB needs a new school on the north side of the Saint John River. We call it Fredericton North for short. The new school will be heated by a wood pellet fired boiler. This is a pilot project for the NB government as it fullfills a campaign commitment to use bio-fuels to heat provincial buildings. The construction will be completed in September 2012. The project "will provide us the opportunity to gain experience with the highly efficient European wood burning technologies and equipment designs which will be applied on the project.", said Minister of Transportation and Infrastructure Claude Williams.

The boiler will supply 500 kilowatts of energy to heat the 80,000 square foot building. The wood pellet boilers are manufactured by KOB (Viessmann Group) or Binder. Pellets supplies,  boiler operations and maintenance will be tendered. It is expected to require 300 tonnes of New Brunswick manufactured wood pellets annually. The pellets will be delivered in bulk and stored in a steel silo. Automatic controls will engage natural gas boilers to top up the heating demand during extreme weather conditions.

[Atlantic Forestry Review, Sept 2011]

[beenthere]

Gee, I recall a similar "pilot" project to heat a school in northern MN and that has to be about 30 years ago. I visited the pellet processing plant and read about the huge project. Federal funding and state funding, all with intention that it would be a great business and so great for the schools.

And there have been many such projects since then. Wonder what part of the equation they are trying to re-invent?

[SwampDonkey]

You can bet it will be built, whether it's good sense will remain to be seen. But we have a lot of pellet plants here as well, so it's probably a boost for those businesses I suppose if nothing else. Actually, they already have a history in Fredericton of doing the same thing only with sawdust to heat the hospital and the two Universities. But it's (sawdust) a supplement to stove oil. Must be close to 30 years now. ;)

[RickF]

I have no doubt that it can be done. What I'm curious about is whether there will be any savings over traditional heating. I know gas or electric are the common ways to heat around here with coal burning furnaces beings the source before that. I would think that wood pellets would be much cheaper than gas or electric but I wonder if wood pellet furnaces became more popular, if the supply of wood pellets could meet the demand?

[beenthere]

RickF
Welcome to the forum.
Where is "around here" for you?

There are likely a lot of machines that make pellets. Pelletized products have been around for many years in animal feed stock and for a good 30 years making wood pellets. As I understand, the consistency of the wood grind, addatives such as mentioned, moisture content of the wood, species of the wood, bark content of the mix, and the variables go on and on. Once a producer figures out what works best to make the pellet (usually extruded through a die), then it becomes a well guarded secret so the competition (or wanna-be competition) doesn't copy the recipe. After that, the cost of maintaining a sharp die becomes significant. The dirt in the wood grind wears the sharp edges of the holes in the die to make lousy pellets. So a new expensive die is in order.

[SwampDonkey]

The pellets will be outsourced, so the school (government) only buys the end product. The pellet mills I know of are Groupe Savoie, H.J.Crabbe, YSC Marketing Board, one other that slips my mind. The thing is that oil and natural gas are way higher in this country than to the south, so beating the oil and gas drum is a lost cause. ;) Pellets are $240/ton bagged or as low as $180/ton in bulk. A 900 litre stove oil tank costs close to $1200 to fill. They said it will also be supplemented in extreme cold by natural gas. I think the decision to use natural gas is simply to add one more customer to a slowly evolving natural gas market in the Maritimes. That's just a guess. But there is still the notion about burning it to reduce a green house gas, even when it's deep under ground.

[John Mc]

Wondering why they would burn pellets instead of chips. A lot less embodied energy in chips.

[SwampDonkey]

Sawmill supply, many sawmills in the area closed. Planer chips go to pulp mills as do mills that chip slabs from debarked logs. Hog fuel is also used by mills and the Fredericton heating plant for the Hospital and two Universities. That supply can sometimes be tight when a local mill goes down. You don't see piles a waste around a modern mill. I suspect the province is also trying to help grow the pellet industry which uses low grade wood. No shortage of that, just ask the loggers trying to sell it. ;)

[thecfarm]

I thought a school did a pellet system too,this was in 2009.
http://www.keepmecurrent.com/lakes_region_weekly/news/article_719a95ac-efdc-11de-9f6c-001cc4c002e0.html

Pellets are easier I suppose to feed into a system. The school has a big hopper that a truck comes and fills up. All automatic,nobody has to do much with it. I suppose the chips would leave more ashes to dispose of. Storage is a factor too
Can get a lot of BTU in a much smaller space if they are pellets instead of chips.

[SwampDonkey]

Yes good points and also the uniformity factor and moister issues, and maybe clogging and feed rate.

[John Mc]

A number of schools, and a college in my area are heating with chips. It is important that the chips meet certain specifications. With good chips and good boiler and chip handling design, they are reliable. Unfortunately, there is at least one company around who apparently has no design expertise - they've used combustion chamber designs more suited to burning oil, resulting in poor efficiencies. Their chip handling leaves much to be desired as well.

One of he saw mills in the area has been saved by chips. They switched to a biomass chipping operation, and have contracts with some of the schools and other large users in the area.

[beenthere]

Our Gov't is pouring money into the pellet business's.

http://biomassmagazine.com/articles/5832/usda-announces-more-than-160-payments-to-biofuel-companies

More "stimulus".