Carbon Neutral Maple Syrup

[TapTapTap]

The generation of power on your property is an offset only against the scope 2 emissions of your electric utility. Basically, you would use the net of Kwh generated vs consumed from the grid and prorate the result (ie. net divided by external source kwh) against the power used by pumps and RO / filters in your maple syrup operation. If you generate more than you use from external sources, you have zero scope 2 emissons.

I'm a little confused by your explanation. I think I understand you to mean that I can use my excess generation to offset the scope 2 emissions only for the percent of unconsumed power applied to the maple production consumption:

For 2020:
Generation: 21,562 kwh
Consumed From Grid: 16,736 (house and maple operation)
Unconsumed: 4,826 and not sold to off-taker

% = 4826/16736 = 28.84

Maple Production Consumption: 1686

1686 x 0.2884 = 486 kwh at zero scope 2 emissions
1686 x (1-.2884) = 1200 kwh at scope 2 emissions from my power company.

Am I understanding this properly?

ken

[PaulRenaud]

I'm a little confused by your explanation. I think I understand you to mean that I can use my excess generation to offset the scope 2 emissions only for the percent of unconsumed power applied to the maple production consumption:

For 2020:
Generation: 21,562 kwh
Consumed From Grid: 16,736 (house and maple operation)
Unconsumed: 4,826 and not sold to off-taker

% = 4826/16736 = 28.84

Maple Production Consumption: 1686

1686 x 0.2884 = 486 kwh at zero scope 2 emissions
1686 x (1-.2884) = 1200 kwh at scope 2 emissions from my power company.

Am I understanding this properly?

Yes. Apologies for being so obtuse in my hurried explanation.

If your maple syrup consumption of power is 1686 kwh, these are normally your scope 2 emissions. Since you have a surplus of power, it is fair to apply them to your scope 2 emissions by the proportion of consumption related to your maple syrup operation to the total consumption. If you did not have a surplus of power, your carbon-free generation is in theory already accounted for in your state's electricity emission calculations.

My calculation for the surplus gets to the same place via a different route:

Proportion of power consumed from grid due to maple syrup 1686 / 16736 = 10%
Hence 10% of the surplus power is available to reduce your scope 2, i.e. 4826 x 10% = 482.6
Net Scope 2 is 1686 - 482.6 = 1203 kwh

I double checked the GHG Protocol on co-generation. Note that the downstream CO2 emissions arising from the transmission of the amount of offtake is also a scope 3 emission (prorated by the applicability to your maple syrup operation at 10%). I would suggest using the same scope 2 emissions rate for Vermont electricity to calculate this since you are using the same grid for both generation and consumption. This is a bit unfair as it embeds the CO2 for fossil fuels in the transmission costs, so if you can find out the break-out of just the transmission overhead you could use that instead.

It is worth observing that if you used a transfer switch to battery bank to service your maple syrup operation's electrical needs from your onsite generation, you could eliminate your scope 2 emissions entirely and not have to count the remaining excess as scope 3 because you could draw the accounting scope boundary at the maple syrup business. The only reason why the scope 3 co-generation transmission gets counted is because you need to incorporate the surplus generation against your scope 2.

[Michael Greer]

A fascinating thread that got really big, really fast. Thank you for all your hard work. The accounting gets over my head pretty quickly, so it's good that somebody (else) is doing the work.
My own little operation (500 taps) uses only sawmill scrap as fuel. My supplier typically burned his scrap piles once or twice a year, just to get rid of it. If seems to me that I'm taking that (wasted) carbon and making it produce something tangible and useful. My operation also packs only in glass, thereby reducing the creation of, and disposal of all those plastics. My glass goes out into the mostly local community, and much of it comes back to me for re-use. I'm pretty frugal with equipment, and take care to wring every bit of use out of gear before sending it to the scrap yard to be recycled.
Lately I've had what could be called existential thoughts about my sugaring operation. I burn fuel to make a product...but is that product necessary at all. Wouldn't we all be healthier if we got rid of the sugar in our diets altogether? It's a troubling thought.

[PaulRenaud]

Lets not lose sight of the fact that maple syrup is the healthiest sweetener available. It was traditionally used by the First Nations of North America to rebuild their bodies after a long winter and is the richest natural source of anti-oxidants. Nature's own energy drink!

While you only mentioned this as an aside to bolster your argument, it is kind of a pet peeve of mine. You need to keep in mind that you're getting a whopping dose of sugar along with those antioxidants, vitamins and minerals. Blueberries, cranberries and other plant-based foods contain far more antioxidants than maple syrup, with WAY less sugar.

While it's true that indigenous peoples of North America consumed a good bit of maple sugar in the spring, it was mainly for subsistence. Maple is what was available at that time of year, not to "rebuild their bodies." Maple sugar, like all other sugars, are mostly empty calories. You'd need to consume over a quart of syrup DAILY to get the needed dose of many minerals (zinc, iron, potassium, calcium, etc.) that maple is fairly high in.

Don't get me wrong...I prefer maple syrup to many other types of sugar, but I always cringe a little when people talk about health effects of maple. It is mostly advertising "spin" in my way of thinking. Yes, in some ways maple syrup is marginally better than other sugars, but it is still MOSTLY sugar. The only reason it is better is that it is far less refined, so the small amount of "good" stuff has not been stripped out. The argument is sort of like would you rather get hit by a car driving 60 mph or a truck driving 80 mph. Neither are particularly healthy except in comparison.

[TapTapTap]

At the risk of being repetitive, once again, using fuel from a renewable or recycled source, including wood scrap that would otherwise emit CO2 as it rotted, is insufficient because it is based on a renewable CO2 cycle measured over the lifetime of trees (over 100 yrs). Let alone the "leakage" that is presumed to occur in the eventual update of that carbon due to loss of forest and ocean capacity to absorb it.

So Paul, I guess you need to continue to be repetitive because I don't understand your point and I assume others don't either. Can you explain, in simple terms, the logic that using scrap is not carbon neutral. It seems that whoever has done the harvesting should take the burden of the consumption, not the user of the scrap. Can you also explain how you would credit, or assign carbon, to firewood harvested from dead, down, diseased trees?

Even my forestry management plan requires me to cull out the less healthy/desirable trees. For example, poplar and white pine. I know first hand that these trees can be very destructive to their neighbor trees since they grow so fast and taller that they inevitably die earlier and often crash down on the desirable trees. Another example is with ash trees for the concern for the emerald ash borer.

Thanks
Ken

[PaulRenaud]

So Paul, I guess you need to continue to be repetitive because I don't understand your point and I assume others don't either. Can you explain, in simple terms, the logic that using scrap is not carbon neutral. It seems that whoever has done the harvesting should take the burden of the consumption, not the user of the scrap. Can you also explain how you would credit, or assign carbon, to firewood harvested from dead, down, diseased trees?

OK, let me try to break it down into more detail:

1. When you burn any fuel via combustion the process emits CO2. For example, if you burn a full cord of wood on an evaporator that is 20% efficient (as most wood evaporators are), you will emit over 2500 Kg of CO2 (over a metric ton) regardless of how climate friendly fuel source. The more you burn, the more CO2 you emit. To be carbon neutral, you need to ensure that all this carbon is sequestered.

2. The argument for using a climate friendly fuel source, such as wood pellets made from sawmill scrap, harvesting wood from only dead or downed trees, using scrap lumber, recycled veggie oil, etc. is based on the premise that this emission would have occurred naturally anyway, so that these emissions are non-additive, and that natural sequestration would have eventually absorbed them. But what about the timing of this quantity of emissions?

3. This non-additivity is only "true" if you look over the 100-200 year cycle of the lifetime of a tree and if you assume no leakage due to loss of sequestration capacity in the forest (due to disease, invasive species, biological transition caused by climate change, etc.). Left alone in the forest that tree would grow, die, fall down, decompose over its lifetime. And during the end of that life-cycle, the roots would continue to sequester carbon, as wood some of the leaf litter that decomposes into the humus of the soil (typically the underlayer of litter and debris), so roughly 75% of the carbon of the tree would eventually be released to be taken up by the living trees in the forest.

4. But not all at once! In all scenarios where we use a renewable fuel, we are accelerating the rate of CO2 emission that would have otherwise naturally occurred as well as impacting (to some degree) the forest's eventual natural sequestration uptake of it. The rate of release of CO2 during that last part of the cycle is based on the half-life of the decay rate in the forest, which depends on conditions as well as the cause of the natural death of the tree (insects, disease, old age, etc.) but can be expected to take at least 7 years. So by harvesting that tree and burning it, we are accelerating the CO2 release by at least 7 years.

4(a) Use of wood harvested from living trees. Depending on its age at the time of being cut, that tree's lifecycle of CO2 sequestration is cut short (bad pun). It could have grown more (how much depends on the tree marking methodology, e.g. not much more if only diseased trees are cut, a lot more if healthy trees were cut) and therefore sequestered more. The stored carbon will be released far faster - an acceleration of possibly several decades or more, and there is less remaining sequestration capacity in the forest to take up carbon from the other fallen trees.

4(b) Use of wood harvested from dead and downed trees. In this scenario we are not cutting short the tree's lifetime CO2 sequestration period, but we are still accelerating the decomposition period. By removing the tree from the forest, we are impacting the debris that would otherwise be used as fertilizer by the remaining live trees.

4(c) Use of wood harvested from scrap lumber. In this scenario the impact of 4(a) loss of sequestration was caused by others, but we are still releasing the stored carbon in that fuel faster than it might have decomposed on its own in a landfill. The fact that the loss was caused by others is cold-comfort.

5. So in effect, when we attempt to make the argument that climate friendly fuel is non-additive, it only works if you ignore the timing of emissions and you assume that the forest capacity to sequester is not impacted. We could quibble about the degree of impact on the residual forest's ability to sequester and a counter-argument might hold more water if the world were already carbon neutral, but it isn't and global forest sequestration capacity is being seriously degraded by increased number of wildfires, invasive species, etc. caused by climate change with accelerating impacts. Timing matters. We only have until 2030 to get a grip on the irreversibility of climate change and that is less than a decade away.

6. Please don't get me wrong. I also use climate-friendly fuel sources exclusively. Climate-friendly vs fossil fuels makes a huge difference in the reduction of additivity of CO2 into the atmosphere over time compared to other fuels (and there is no avoiding the use of a fuel source to boil sap either directly via convection or indirectly via steam). It is definitely a good thing to use climate friendly fuel, just not good enough.

We need to think globally while acting locally, which is why our approach is to ensure that your annual emissions are balanced by the sequestration of the living maple trees that you harvest for sap. No acceleration, no additivity of any kind.

Hope this is helpful, paul

[PCFarms]

Further, while I understand that a single tree may exist over 100 years and in isolation does not make a significant contribution to carbon emission in a 1 year period and therefore cannot account to sustainability of an operation, over tens of thousands of trees in a forest, you can do this. There are thousands of trees rotting in my forest today, probably averaging many trees completely rotting everyday, releasing CO2. A forest can reliably supply firewood coming from 100 year old trees every year.

On one hand If you account for the growth of the trees to make the positive in your carbon equation, you certainly need to think about negative in the forest as well. The negative is made by decomposition and potentially burning of firewood. In this sense, burning firewood does not increase the amount of CO2 released, it just happens in a shorter timeframe. There would be a one time hit on the carbon equation when you start to use the dead wood as a fuel source, but once the 'life cycle' of a rotting tree is complete, this would become 0, and the carbon debt would be repaid when the maple operation ceases.

SO if you are an existing maple operation that has been using wood for at least a decade already, you have already emitted that 1-off carbon amount by accelerating the decay of wood, and you could argue, that looking forward from today, there is no net impact by continuing to burning wood.

[TapTapTap]

4. But not all at once! In all scenarios where we use a renewable fuel, we are accelerating the rate of CO2 emission that would have otherwise naturally occurred as well as impacting (to some degree) the forest's eventual natural sequestration uptake of it. The rate of release of CO2 during that last part of the cycle is based on the half-life of the decay rate in the forest, which depends on conditions as well as the cause of the natural death of the tree (insects, disease, old age, etc.) but can be expected to take at least 7 years. So by harvesting that tree and burning it, we are accelerating the CO2 release by at least 7 years.

So as I think I understand:

Downed and dead trees can be considered to have 7 years of carbon emission through their process of decaying. Therefore, it seems that if you account for the yearly emissions from burning the wood and credit back the carbon that would be emitted from the decay process you would be back to a carbon neutral accounting after 7 years of this practice.

year 1 = 100% emissions; year 2 = 100% - 100%/7 = 92.86%; year 3 = 100%- 100/7 - 100/7 = 85.7% ...... year 7 = 100% - 7 years of credit back = 0%

Am I understanding this correctly?

Ken

[PaulRenaud]

Further, while I understand that a single tree may exist over 100 years and in isolation does not make a significant contribution to carbon emission in a 1 year period and therefore cannot account to sustainability of an operation, over tens of thousands of trees in a forest, you can do this. There are thousands of trees rotting in my forest today, probably averaging many trees completely rotting everyday, releasing CO2. A forest can reliably supply firewood coming from 100 year old trees every year.

On one hand If you account for the growth of the trees to make the positive in your carbon equation, you certainly need to think about negative in the forest as well. The negative is made by decomposition and potentially burning of firewood. In this sense, burning firewood does not increase the amount of CO2 released, it just happens in a shorter timeframe. There would be a one time hit on the carbon equation when you start to use the dead wood as a fuel source, but once the 'life cycle' of a rotting tree is complete, this would become 0, and the carbon debt would be repaid when the maple operation ceases.

SO if you are an existing maple operation that has been using wood for at least a decade already, you have already emitted that 1-off carbon amount by accelerating the decay of wood, and you could argue, that looking forward from today, there is no net impact by continuing to burning wood.

This line of thinking overlooks the fact that the forest is already in a natural balance - absent the activities of humans. If the dead trees rotting in your forest were put there by Mother Nature, and not you, then all is good.

Climate change is caused by human activity according to the published and accepted science. So, in examining our carbon footprint, we need to look at the impact of our own action and ensure that they are mitigated by natural mechanisms.

Secondly, timing of carbon emissions matter. We do not have decades to pay back the deficit we are currently creating. We have less than 8 years and ducking human responsibility by blaming natural mechanisms (fires, volcanos, rotting trees in existing forests) is insufficient.

[PaulRenaud]

So as I think I understand:

Downed and dead trees can be considered to have 7 years of carbon emission through their process of decaying. Therefore, it seems that if you account for the yearly emissions from burning the wood and credit back the carbon that would be emitted from the decay process you would be back to a carbon neutral accounting after 7 years of this practice.

year 1 = 100% emissions; year 2 = 100% - 100%/7 = 92.86%; year 3 = 100%- 100/7 - 100/7 = 85.7% ...... year 7 = 100% - 7 years of credit back = 0%

Am I understanding this correctly?

I think you are overlooking the fact that each year you accelerate emissions by another 7 years. Your timeline shows the impact of only one year.