Carbon dioxide is the most commonly produced greenhouse gas. Carbon Sequestration is the process of capturing and storing atmospheric carbon dioxide. It is one method of reducing the amount of carbon dioxide in the atmosphere with the goal of reducing global climate change. The USGS is conducting assessments on two major types of carbon sequestration: geologic and biologic. …The U.S. Geological Survey
The Hamakua Group is a 501(c)(3) public charity as determined by the IRS. Donor’s contributions, bequests, transfers or gifts to The Hamakua Group are tax-deductible for federal income tax purposes. At The Hamakua Group your donations go only toward the accomplishment of our Projects.
The Hamakua Group
150 Hamakua Drive, #729
Kailua, HI 96734
(808) 492-9839
Questions and replies both occur in the original comment.
The following questions were submitted to The Hamakua Group by Eden Perez, Cyrus Kuhr, Dante Murry and Zalea Douglas, all students in the SCII Course at Hawaii Community College.
1. According to your website, the three primary greenhouse gases released into the atmosphere are methane, nitrous oxide, and carbon dioxide. It is also noted that your biochar program contributes to the sequestration of carbon dioxide. Could you please clarify whether methane, nitrous oxide, or any other harmful gases are also sequestered through the application of your biochar?
To be more precise it’s not the act of biochar field application which results in CO2 sequestration. Carbon dioxide is drawn out of the atmosphere by the providential action of photosynthesis. The decisive issue is what we choose to do with that carbon now incorporated as part of the molecular structure of the plants which absorbed the CO2. Here’s an example, consider a single corn stalk in a 100 acre farm field in Iowa. The corn kernels will likely be processed into food for human or livestock consumption. Our concern is what we do with the remainder of the stalk/husks and more specifically the photosynthetic carbon which they now contain. If we incinerate it or let it decompose in nature that carbon will be converted back into CO2 and returned to the atmosphere, ie., the opposite of sequestration. Alternatively, if we use pyrolysis (heat & no O2) to convert the leftover stalk and husks into biochar that same carbon is now sequestered in the biochar which is ~90% stable carbon.
By extension modern pyrolysis equipment is capable of applying this same process to a vast array of waste, well beyond farm residues.
Regarding methane and nitrous oxide, using biochar in conjunction with common farm practices of decomposition and/or in conjunction with composting can reduce the emissions of these two greenhouse gases which these processes would otherwise produce. This is due to biochar’s ability to adsorb these two gases prior to their release into the atmosphere.
2. Additionally, a diagram on your website indicates that your program is capable of capturing carbon dioxide effluents. Could you elaborate on how this process functions?
The phase “More efficient local food production with captured carbon residue“ refers to: employing a pyrolytic conversion (recapture) of municipal and farm waste carbon (biomass) into biochar to nourish soils and improve farm productivity, rather than allowing such waste to be incinerated or decomposed allowing its carbon to reenter the atmosphere as CO2,
3. We are also interested in the operational aspects of your pyrolysis furnaces. What is the approximate cost of operating these furnaces, and what is the scale of your current operations?
These are useful questions to ask but first the context within which the operation will be developed needs to be understood. The Hamakua Group is a nonprofit, not a retail business structured to make money. It was initially conceived to be a smaller entity working within Oahu’s farming communities with a “cooperative” organization. Farms would donate their waste to the “Coop” to earn “credits” to be subsequently used as tokens to receive biochar back from the Coop which it had meanwhile created from various collected waste biomass sources. That sort of arrangement.
But now, as various pyrolysis systems are maturing with significantly expanded lists of acceptable biomass feedstocks (well beyond farm waste), that original coop system seems merely quaint. The massively expanded variety of material considered as potential biomass so increases the volume of available biomass that such a system could compete with the legitimacy of our current H-Power system of incineration. That should be the scale of our planning, which likely means City & County and/or State involvement, and the sourcing of funds. It changes the operation from private to a public one that emphasizes co-benefits to our community as well as serving its more general responsibility of climate mitigation.
It is also the scale on which PYREG operates. According to correspondence with them, their smaller unit, the PX500 model, has a minimum input capacity of 800 tons biomass /year with the expectation of 24/7 operation. The capital expense of this unit is ~ $1.15 million. A site for the pyrolyzer would also need to be developed, however there is already a possibility of using the current “Transfer Site” which is located just mauka of Kailua. It is already the initial drop-off point for waste collection for that section of windward Oahu. Sorting and processing could take place there as well. I’d guess another capital expense of $1-1.5 million for development and installation on such a site.
One of our next steps is to contract a local consulting environmental engineering firm to use PYREG’s assistance to do a plausibility study to confirm the savings and costs of integrating a modern carbonization waste management operation with our current waste system. And to present it to the appropriate government agencies.
For every ton of biomass waste run through a biochar pyrolyzer and not incinerated at H-Power that waste’s now stable carbon is sequestered in biochar and not emitted to the atmosphere. Modern pyrolyzers are self-sufficient. Their effluents meet environmental air quality standards. They largely burn their own waste products to fuel their own operation.
The Hamakua Group has not purchased nor facilitated the purchase of a biochar pyrolyzer. We do though seem to be at the fore-front of the biochar movement in Hawaii, which is several years behind the mainland. The information we present here and elsewhere is in the form of a proposal of an innovative and timely strategy to use our island waste to combat climate change. And to directly benefit local farms with co-benefits, as described on the website.
4. Your proposed action plan mentions that biochar will be deposited into acidic soils across Hawai‘i. Could you specify the locations of these soils and indicate the quantity of biochar intended for each area? Furthermore, does your organization operate across all of the Hawaiian Islands or only on select islands?
As we begin, there presumably will be a single pyrolyzer so only Oahu farms will be candidates for biochar field applications, at the discretion of their owner/operators. Those application rates and timing need to be based on a farm’s individual soil characteristics vs. available biochar’s content analysis. We’ll need participating professional agronomists to fine tune those applications and to track the subsequent productivity results.
The primary method of recruiting farms to participate will initially be promotion of the expected improvements in soil fertility and consequent productivity of biochar treated fields. I feel the biochar should be offered to farms free of charge as part of this program. As those positive expectations come to be supported by real time increased crop productivity values biochar will begin to promote itself within farming communities.
5. In terms of input materials, how much waste biomass does your organization receive from farms, property owners, or other similar sources? If supply is limited, do you ever need to harvest organic material independently?
Over the last few days I’ve added a quick calculator to The Hamakua Group website. I did this to emphasize how much biochar and by extension biomass we’ll need to service even a subset of Oahu farms, totaling 22,756 acres under cultivation in 2022 (USDA). Using the calculator you can see the need could be massive. That is why I’m so encouraged by PYREG’s published capability of processing such a wide variety of biomass feedstock categories.
Once biochar’s value is demonstrated by empirically improved productivity values the following few years will be characterized by the need for more and more biochar and its necessary feedstock. The bottleneck will not be the need for biochar, but its supply.
6. We also found the link to PYREG on your website quite compelling. Does your organization maintain any form of collaboration with PYREG?
We’ve shared a few emails so they know we exist. At this point nothing more formal than that.
7. Finally, how effective do you consider biochar to be as a climate mitigation strategy? In your view, does it have a significant role to play in the future of renewable energy?
This biochar system’s value is in CO2 extraction and sequestration. It’s a smaller role than that of limiting and hopeful reducing CO2 emissions, but “Don’t let the perfect be the enemy of the good.” All agree we need to advance on all fronts and frankly the progress in emissions reduction remains less than satisfactory.
The system helps to redirect Oahu’s waste stream away from polluting incineration and toward the production of useful biochar and other regenerative products. Forever chemicals are eliminated in biochar production and adsorbed in treated soils. Further, the co-benefits, as I’ve outlined on the website, can help our farmers increase their productivity and the State as a whole decrease its inordinately large dependency on imported food.
With these strategic boxes all checked I’d suggest we can’t afford not to implement such a program.
The pyrolysis system does produce renewable energy but that energy is employed to run the process itself, and/or used to dry biomass about to be consumed. The system is configured to produce biochar, not as a system to provide off-site power.
Bob Gratz
808.492.9839
TheHamakuaGroup.com