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Great wood waste management project

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Very interesting! All over the world and also here in Europe companies develop new processes to convert biomass into fuel. I know at least two companies with similar processes. The problem with their systems is that the equipment and machines are bloody expensive and very often not even available for an industrial size. Such processes go often along with high temperatures and pressures. And that is the challenge. But it does not matter. It is good to have the ideas now. Things will change in a couple of years.
 
There are many of these waste to energy projects.

Spending $15.7 M to save $500,000 is probably not an attractive proposition. It may be more attractive as a demonstration project. Industry would be looking for a project payback occuring within 2-3 years and would never go for something like this.

Since this project will be burning sawdust, there probably is a limited market for the technology. It is only feasible if you are located near a forest products manufacturer.

Not sure how this project will reduce greenhouse gases. The bound carbon materials in the biomass will be converted into carbon dioxide which is a major green house gas. This system will probably release more greenhouse gases than a comparable natural gas fired boiler. Maybe there is some trick with using a single boiler versus multiple boilers?

If the forest waste is not returned to the soil, you are in effect mining the soil of nutrients thereby reducing the future viability of the soil.

The project is good for demonstration, but not the greatest invention since sliced bread.
 
As far as i know the number of such projects is increasting steadily. But i don't believe that the whole concept has to do only with saving energy and money from your own consumprion.
Most of these plants are in fact base load decentralised power plants, so their operation results in the production of clean electricity and heat. In any case, 2-3 years payback period is quite low for any investment. Most of the renewable energy projects have 5-8 years payback.

Now the fact that sawdust and all that biomass produces carbon dioxide when is converted into power, doesn't mean that it ain't renewable energy.
Renewable energy has to do with the constant supply of a natural occuring source. Natural gas reserves are not infinite and sooner or later their amount will be eliminated. Not to mention where are those reserves found (i.e. Alaska, Russian tundras) and how environmentally risky is the drilling in these areas.
 
Just reading the link you posted:

"According to Nexterra, the UNBC project will convert locally-sourced forest waste into clean syngas, enabling UNBC generate economical heat. The system will displace up to 85% of the University's natural gas consumption, contributing to energy cost savings of approximately $500,000 per year. The company also claims that the system will also reduce greenhouse gas emissions by up to 3500 tonnes per year which is the equivalent of nearly 1000 cars off the road."

The project doesn't look to be economical, to be clean energy, nor does the project have the ability to reduce greenhouse gases.

Burning soil nutrients is not really sustainable either.

The lesson learned seems to be it is a method to obtain funding for a project, not to achieve an environmental goal.

 
It 'd be better if you were more specific on what you suggest.
In what way that project ain't achieving environmental goals, when:

- It uses waste wood (not virgin timber) to produce energy
- It replaces non renewable fossil fuels (natural gas)

I repeat that the point is not only to produce less GHG gases but to produce energy from non-expandable resources. Moreover, when the raw material absorbs dioxide during its growth then the total carbon mass balance minimizes, and is a matter of a Life Cycle Analysis to decide how you can make it almost zero.

Not to mention that for fossil fuels that Analysis has no meaning at all.


 
I am not suggesting anything as the issue is too complex for this forum. There are many tradeoffs to the use of biofuels.

You raised the question, is this project technically feasible.

The answer to that, probably not. Just look at the project payback timeframe.

Whether it is really a sustainable biofuel, nobody knows. There is research being done at the present time to answer this question.

Greenhouse gas emissions vary widely based on land use, conversion processes, and end use practices. Your project does not address all these factors. And analyses from many countries show that biofuels are currently a relatively expensive means of reducing greenhouse gas emissions relative to other mitigation measures.

Refer to the UN report on sustainable bioenergy:


The only point that I made was that the project is good for demonstration and prehaps research, but not the greatest invention since sliced bread.
 
The CO2 gets absorbed by new trees, so it is somewhat carbon neutral. Long term growth, 10 yrs? is better for soil nutrients than plowing every year for other crops. Wood waste would get burned anyway at wood products mill.
 
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