Combined Heat & Biochar (CHAB) Markets

CHAB markets

[Part II of a recent presentation I gave at the NE Biomass conference.

Given the emergent nature of markets for biochar at this point in time, my personal opinion is that in the short term it might be best to focus on closed loop scenarios where feedstock, heat and biochar are all provided and used within the same environment. As with my previous post on Biochar Markets, this graphic is not meant to be exhaustive but rather indicative of possible uses for heat, types of available biomass and potential CHAB markets.

Agriculture is one of the largest sources for underutilized biomass whether it is from perennial or annual crops or from livestock. Most of this biomass can be converted into biochar, although some is easier and cheaper to process than others and some biomass makes much better biochar than other feedstock. To take one example, albeit not a local one, coffee generates massive amounts of waste, most of which isn’t usable for many other purposes given high tanins and other content. Converting coffee pulp or tree prunings into biochar and using the heat to dry coffee cherries could allow farmers to sell their harvest as a higher value commodity. They could then use the char on-farm to improve soil resiliency and crop yield which reducing fertilizer costs.

For an example closer to home, maple sugar producers could use a customized CHAB unit as an evaporator for converting sap to syrup and then use the char around the trees to help them manage drought better and to counter-balance acidic soils, something which I’ve heard is a bit of a problem in parts of this region.

Poultry farms are another great closed loop example. While poultry litter does make a great natural fertilizer, often times there is an excessive amount and no nearby markets, especially during winter months when spreading is difficult or not allowed. Poultry litter can make an excellent feedstock for biochar as it has a relatively high nutrient content compared to other feedstocks. Heat can be used in hen houses and biochar can be used as part of the litter or used in wall structures to reduce odors related to ammonia.

At the municipal level, many towns and cities are desperately looking for ways to reduce the amount of organics sent to landfills. Yard waste and the like could be chipped for CHAB systems and the heat used at recycling centers while the biochar could be used by Parks & Recreation departments or provided to taxpayers. An example of this model will soon be found in Stockholm, Sweden as the project won funding from the 2014 Mayors Challenge. Mobile CHAB units which could be shared within a region would be very helpful in handling storm debris and providing heat which could be used for melting snow or used in emergency shelters if needed.

There are countless examples where CHAB technology makes a lot of sense in the commercial realm. Many golf courses tend to have a lot of tree debris and could definitely use the biochar to reduce compaction and improve water management especially out west. Or they could use the char to reduce nutrient leaching into surrounding water bodies. The heat could be used, at least in the cooler months, to heat club houses. Systems that can convert heat to electricity would be especially useful for golf courses.

Another example is related to milling operations. To take coffee again as an example, often this waste is either dumped or burned at the mill level. Converting this into heat and biochar would provide heat for additional drying processes and char which could be used to filter waste water, used in the fermentation process, or used in cement mixes to create drying pavements or storage warehouses or sold as an additional revenue stream.

Sugar cane mills also provide another closed loop possibility. In one operation down in Costa Rica the fibrous leftovers, called bagasse, are converted into biochar while the heat is used to make steam which is used for the boiling process. The biochar is used on sugar cane fields and also sold to plant nurseries.

These are but a few examples where combined heat & biochar technologies could be used. Once a market for biochar is more established, there are likely to be even more potential customers for CHAB technologies. However since selling biochar is unlikely to be part of the core business for some of these customers, they are likely to be more interested if off-take agreements can be established for any biochar produced.

Dr. James Hansen & Biochar

Dr Hansen

This week I attended a presentation that Dr. James Hansen gave to a packed house at a local community college. As with most things I’ve heard or read from the likes of Dr. Hansen or Al Gore or Bill McGibben, I have mixed emotions. Yes, I am happy they are all issuing the clarion call for action on climate change. Without a doubt this type of thing is sorely needed and I am thankful that high profile people like this are willing to dedicate so much of their energy to education and outreach.

But I would hazard a guess that these messages are rarely heard by the eco-non-literati and most of the eco-literati that I know already understand the basic facts underlying of the impending crisis. Hearing more of the nitty gritty from climate scientists about how bleak our future is likely to be, can get a tad depressing which is hardly the best motivator for most humans.  Hearing more about existing, viable ways to decarbonize at the individual, community, national and global scale would seem like a much better use of airtime. Several of the questions asked during the Q&A part of the program support this notion as  they were focused on ‘what can we do or what gives you hope’.

Knowing that Dr. Hanson has spoken positively about biochar in the past, I was curious to see if he was going to bring it up, but as he was concluding his presentation, nary a mention (frustrated sigh). But then when answering the very first question, he brought up how he and his eldest granddaughter have been experimenting with biochar on his small farm in Pennsylvania. Hallelujah! But then the brakes seemed to come out. There seemed to be some hesitancy around his conclusions about the role biochar could play in climate change mitigation. He seemed to conclude that it’ll be very difficult to get significant amounts of biochar into the ground. While I definitely don’t disagree with that conclusion,  every other decarbonization pathway that I have ever heard of will also be very, very difficult. And expensive. And in some cases dangerous.

Most scientists are understandably cautious and like to have a deep understanding of something before they recommend it. Their scientific integrity depends on this type of deep understanding. Interestingly though, more and more climate change scientists are venturing outside of their comfort zone to urge action on climate change – often this action is of the political variety or via protesting certain actions which are obviously going to exacerbate climate change. However, to misquote one of my favorite Wendall Berry quotes “Protesting is necessary, but not enough”. Perhaps it is also time to start giving people more information and tools on the best options available now for rebalancing carbon, one of which is surely biochar.  Or perhaps, as my colleague HPS recommended, its time to get Dr. Hansen a Kon-Tiki kiln so he can see that making 1 ton of biochar a day doesn’t really need to be that hard or that expensive!

Markets for Biochar

Biochar Markets

Yesterday I had the pleasure of presenting at the NE Biomass Conference in Portland, ME – which is simply a gorgeous place. [A major hat tip to all the good folks at ClearStak that are really helping to bring biochar to the attention of those within this industry!] My talk had two components: markets for biochar and markets for combined heat & biochar (CHAB) technology. Below is a modified version of the part where I discussed biochar markets.

The Biochar Markets graphic outlines current & potential biochar markets using 3 different attributes for each market segment:

  1. Volume of char that could be sold
  2. Value or potential price point that biochar could be sold within these markets
  3. Market Readiness – is it a current or future market for biochar

Agriculture has to-date garnered by far the most attention in terms of research and market focus. In part this is due to the multiple benefits associated with biochar such as improved plant yield and reduced fertilizer needs. But it is also partly due to the sheer volume of char that this market could represent. That said though, it is not without its challenges. Different soils and different crops respond differently to biochar making site specific recommendations for use and application techniques difficult. Low value crops that generate less than $1K per acre in revenues such as corn or soybean are unlikely candidates for biochar right now as the price point for char is simply too expensive for it to make economic sense. The best ag markets for biochar at the moment seem to be high value specialty crops (e.g. marijuana is a big one!) or in geographies that are suffering from droughts where biochar can improve water management.

I suspect another key ag market to keep an eye on might be crops grown in soils contaminated from a build-up of metals commonly found in pesticides or livestock manure or other sources. Crops such as rice or apples have been found to have significant issues with arsenic and cocoa beans have been found to have high amounts of lead and cadmium in some regions. Certain biochars can render these metals to be plant unavailable. So in these situations using biochar could mean the difference between being able to harvest and sell crops sown in tainted soils or having to let the land go fallow.

The gardener market has been one that many initial biochar producers seemed to target probably because char can be sold for much higher prices. Prices of $30 – $50 per 5 gallon, or $1 per pound are still common for this category although the market is getting much more competitive as biochar production capacity increases. The challenges in the market are at least twofold: low market awareness and a low potential for repeat sales. The latter is due to the fact that biochar tends to be a once and done kind of product. This obviously has a huge impact on customer acquisition costs.

The remediation market seems to be slowly gaining traction and I think could be a very interesting market. Where there is money for brownfield remediation biochar could be a lower cost alternative than some other options. In some demonstration plots biochar was left in situ and found to promote plant growth which leads to less erosion and less groundwater contamination. I’ve heard some murmurings about using biochar on fracking sites but I don’t have any specifics on that.

These three categories are all effectively single use markets – which is great for the consumer, but not so great for biochar producers. Most of the rest of the markets I will cover tend to be repeat markets, which is obviously critically important for sustained biochar production.

Filtration could be another very interesting market for biochar on many different levels. Activated carbon is often used for filtration and biochar can be designed to perform nearly as well as activated carbon and generally will cost a lot less. In addition biochar has a much lower carbon footprint than AC. Low cost filtration in the developing world is another big opportunity for biochar in everything from food processing to sewage treatment.

The use of biochar in livestock feed is one market that has been attracting a lot of interest especially over in Europe where a large percentage of the biochar being sold is for this purpose. Biochar acts as a binding agent in feed and has been shown to have multiple benefits to animal health as well as improved weight gain. Many large scale poultry and livestock operations use antibiotics and/or arsenic to stave off health issues but this has proven to be a public health issue and sustainable alternatives such as biochar are likely to be much more attractive moving forward. Reduced odors related to manure have also been documented. Initial research has also indicated that it could help reduce methane emissions related to cattle but this still needs more research to be fully validated. I recently heard that the first US biochar producer has received approval to market their biochar as a feed additive and I think we will see a lot more of this moving forward.

Biochar building materials has the potential to be a huge market within the next 5 – 10 years. Initial demonstrations of using biochar plaster in a wine cellar in Switzerland proved the concept had merit as it helped to significantly control humidity. Based on the positive results, the Ithaka headquarters was retrofitted with biochar plaster showing further benefits which included improved insulation, sound and odor reduction. Further testing has been going on to determine the best types of chars and the best recipes for mixing biochar with cement, lime and other additives to optimize different cement or plaster properties.

Biochar use in packaging materials is at the very beginning of development but could also prove to be a strong recurring market. Based on a small prototype of biochar made from coffee chaff and pulp we created what we’ve dubbed as ‘chardboard’. Chardboard may have an advantage over biodegradable packaging which is quickly gaining market share, in that it is actually ‘bioUPgradable’ meaning that even if sent to a landfill it can have positive impacts such as sorbing toxins and sequestering carbon as opposed to biodegrading and off-gassing methane.

The world of 3D printing materials is changing by the day. Filament materials are no longer limited to just plastics or metals, 3D printing materials include ceramics, paper, sugar, even seaweed! We’re (by this I mean the Ithaka Institute) convinced that biochar will be not only a viable material for 3D printers, but a very versatile and sustainable one moving forward.

Another fascinating area of research for biochar use is in microbial fuel cell technology. MFC is a renewable form of energy that leverages microorganisms to generate electricity while they degrade organic matter. The use of biochar has shown promise in this arena due to its chemical stability and good electrical conductivity. We are definitely a few years or more away from seeing this kind of thing commercialized but this could be an excellent recurring market for biochar.

For some carbon offsets represent the holy grail of biochar markets. However this is really a big unknown at this stage as markets for offsets are still tenuous, prices for offsets fluctuate like penny stocks and biochar has yet to gain approval as an offset product. But this could all change in the not too distant future as there are many folks working on getting biochar on the radar of various carbon markets.

Patently Ridiculous

Patently ridiculous

At the last North American Biochar Symposium I gave an Ignite presentation called ‘Balancing the Hope & Hype of Biochar’. One of the subjects within the presentation was the influence of patents on the biochar markets. Quoting myself, I said: “Patents may lead to pay-dirt for a fortunate few, but they often create more hype than hope. And they can constrain more collaborative, creative solutioneering!” I stand by this statement more than ever especially given some of the shenanigans happening in the biochar world of late!

While I am not a complete detractor nor an expert in the realm of patents, I do believe the original intent of patents (i.e. allow individuals or companies to recoup funds invested in developing a product by providing a period of time in which others cannot pinch your technology) has morphed into a beast which often does more harm than good. There is a notion, or perhaps even an industry, known as ‘patent sitting’ or ‘patent trolls’ where someone or some company patents something so vague yet has no intention of ever taking the concept beyond the idea stage. Then these folks run around and claim anyone in the space must pay them a licensing fee. This is certainly not unique to biochar and has hurt companies large and small. Luckily President Obama is on the case. He was quoted as saying this about patent trolls “they don’t actually produce anything themselves, they’re just trying to essentially leverage and hijack somebody else’s idea and see if they can extort some money out of them.”

Patent sitting is happening in the biochar world, at least in the US. There is at least one patent that is so broad and vague that it seems to claim that the patent owners have the sole ownership of  the very notion of biochar itself as well as any biochar producing technology. This is patently ridiculous. That is akin to trying to patent charcoal (kissing cousin of biochar). IF anyone should have the rights to that sort of patent it would be all the indigenous people around the world that have used charcoal/biochar/Terra Preta in soils for millennia.

Rumor has it that various biochar companies have been sent legal letters stating that they must pay up even when the production technologies and conditions, the feedstocks and the resulting biochars are wildly different. Redirecting the already scarce funds being spent on developing biochar markets and education to pay for lawyer’s fees or even licensing fees without merit is exactly the wrong direction for the biochar industry.

Extortion. The president’s words, not mine. But it’s hard to argue with that conclusion.

Will indigenous people using biochar be the next to be sued?

Disaster Recovery & Biochar Part II

Kiln&Kaboodle

Possible items for a Biochar Based Bounce Back kit

The recent devastation in Vanuatu and the availability of low cost biochar producing kilns has spawned some more serious and targeted conversations amongst some of my favorite biochar people in the land down under. Many organizations play critical roles in disaster recovery. One that is especially adept, from what I have recently learned, is Rotary International.  They have partnered with Shelterbox to provide temporary housing and other emergency supplies to victims of disaster. Building on the concept of a readymade kit for disaster scenarios, my down under biochar buddy Frank and I pondered what kind of biochar kit would best help victims to convert downed biomass into biochar to be used in different ways. [I’ve previously blogged about this Disaster Recovery and biochar and biochar should be a prepper’s best friend]. Here are some initial thoughts for suitable items.

The core of the kit is a kiln to convert biomass into biochar. While there are many different technologies that could be used to convert downed biomass, I am a big fan of the Kon-Tiki Kiln for several reasons. [Full disclosure, although the development has been open source, it was driven by the Ithaka Institute of which I am a part.] The kiln is low cost (various sizes available but all under <$4K), has low emissions, can handle relatively high moisture feedstock and produces very good biochar as per testing done in Europe. The ability for heat recovery is being tested and will soon be available as well.

Although the kiln doesn’t require biomass to be chipped, trees and limbs do need to fit into the kiln so hatchets and pruning shears are a necessary part of the ‘kaboodle’. Thermoelectric conversion technologies such as the Power Pot X could enable victims and disaster relief workers to not only boil water for both sanitary and cooking purposes but they can also charge phones and other USB accessories. A solar pump will help get the quench water from the tote to the kiln. If the biochar is going to be used as a soil amendment, human urine could be used instead of water so having a few 5 gallon buckets with ‘luggable loo’ tops to divert this ‘waste’ for use as a quenching liquid would be ideal. Another use for the buckets, which could be filled with other emergency supplies to optimize shipping space, is for water filtration. Biochar could make an excellent, locally producible filtration media for emergency relief locations. Cooking accessories such as grills or spit roasts would also make a nice addition to the kit.

Depending on the situation, additional items (e.g. trowels, mixing equipment, brick molds, etc.) could be included that enable different end uses for the biochar such as building materials.

Training on biochar production and various end uses would obviously be required, but once trained, local residents would have the tools to enable their communities and their soils to bounce back.

Perhaps, in honor of the ancient cultures who figured out how to convert their ‘waste’ into highly fertile soils called Terra Preta, we ought to dub the process of converting disaster debris into tools for healing soil and water  ‘Disaster Terra P’!

Aging Infrastructure = Carbon Sequestration Opportunity

 

infrastructure

John Oliver recently had the most brilliant riff on the sorry state of U.S. infrastructure. Dams, bridges, tunnels and roads are crumbling around us. The need for repair is undeniable. The cost for repair is astronomical. The funding mechanism for repair continues to be a political football. (why am I not surprised?)

Since we apparently have some time before repair begins, let’s set aside the economic cost for a the time being. Let’s consider the ecological cost of all of these needed repairs for a moment. What do all of these infrastructure projects have in common (besides job creation)? Concrete. Lots and lots of concrete. Concrete, or more specifically cement – the primary component thereof, is not just heavy, but carries a very hefty carbon footprint as well. The cement industry alone accounts for 5% of the world’s GHG emissions. The emissions are partly due to the fact that the production process pulls out CO2 from limestone to get to the good stuff – calcium oxide. A good chunk of the rest of the emissions comes from the energy needed to produce this reaction.

What if there was a way to repair infrastructure without incurring such a heavy footprint? What if, instead of incurring a net positive carbon impact, there was a way to actually sequester carbon amidst all of the newly repaired infrastructure? Here is how that might be possible.

One of the suggested solutions for mitigating cement’s emissions focuses on blended cements. Sadly they suggest coal fly ash and blast furnace slag as blending agents, both of which may contain toxins. Fortunately regulations may prevent those particular blends from becoming too popular. Blending with biochar could be the solution to the carbon woes of cement in more ways than one. Not only might it be feasible to use the heat from the biochar production process to induce calcination (separation of the ingredients in limestone), but the biochar produced could be the blending ingredient of choice. Research on the use of biochar in building materials is moving along with great promise and enthusiasm in Europe yet curiously on this side of the pond it is still very much in the grass roots stage.

It sure seems like a (dam) fine time to turn such a dire problem into an opportunity. Perhaps it is time cast off our tunnel vision and create the road less traveled with biochar blended concrete. As the saying goes in the world of deep change, this would surely be ‘Building the Bridge as you Walk on It’!

 

Could biochar perc up your leach field?

perc

Recently Justin, an uber green urban planner I know that is optimizing his new homes’ footprint, asked me about the possible benefits of using biochar to improve the longevity and efficiency of a septic system. Great question! I’m not actually aware of anyone that has dipped their biochar toe into this particular area but it definitely got me pondering possibilities. I’ve already blogged about biochar in French Drains but septic systems offer even more possible opportunities for biochar.

Nearly 30% of American households are reliant on residential septic tanks and surrounding leach fields to process their own wastewater. Before breaking ground to build a house in an area not connected to a municipal wastewater system, a percolation or ‘perc’ test needs to be done to see if soil drainage is sufficient or if a leach field needs to be installed. If you are planning to build on heavy clay soils, expect to fork out plenty of cash to improve drainage. If you need to head in that direction, adding biochar to a leach field could be a great way to filter water before it heads down into the groundwater zone or local water bodies. It could also provide quite a nice carbon sink opportunity if you are looking to build a net zero footprint home especially if the char was made on-sight using some of the trees or other biomass uprooted to make way for the leach field!

Septic tanks themselves might benefit from the introduction of biochar as well (heck maybe they could even be built using biochar concrete!). Septic tanks are anaerobic environments meant to hold solids while allowing most liquids to pass through into the leach field. A few studies (not nearly enough!) have shown that introducing char to an anaerobic environment can have beneficial impacts such as boosting methane generation. But since septic tanks aren’t built for methane capture (no doubt some enterprising engineer is hard at work to come up with a mini generator from septic tanks?), boosting methane isn’t a desired outcome for these systems. However getting rid of some of the grease and fats that clog up the system could potentially extend the period between getting tanks pumped out as well as the overall life of the septic system. By proving housing for beneficial microbes that feed on just such a diet, biochar may be just what the septic system doctor ordered.

There is though, the challenge of how to get the char into the tank. Not to worry, this is not as challenging as it might appear at first flush, er blush! There are at least three easy ways to do it:

  1. For those ingesting char for health purposes as I do on occasion to keep my tummy in good running order, char will go down the tubes (first yours, then the septic systems).
  2. For those using biochar in body care products (e.g. soap), char will swirl down the drain in the bath water
  3. For those with a garbage disposal, a handful of char tossed down the gullet will keep odors at bay while charging the septic tank.

If none of the above is relevant, you can always toss a handful of char into the toilet and watch it swirl away.

Biochar and snow

biochar & snow

How can biochar & snow removal complement each other?

Like nearly everyone in the northeast, I am just a tad tired of the white stuff at this stage of the winter. My sympathies go to Boston as they have been particularly hard hit this year having welcomed 77” of powder so far and looking likely to reach a new record. NPR recently ran an enlightening interview about a snow removal service in Boston which naturally got me thinking of all new uses for biochar.

Logically when you have that much snow, it’s got to go. Moving it left or right just isn’t sufficient when space is limited. Snow removal, it turns out, can be a very, very expensive line item. (Canada spends about $1B/year!) Methods for removal include pulling, casting, winging back or the most expensive: hauling/dumping. Not surprisingly many places are not too happy with having lots of urban snow dumped anywhere near them given the high levels of salt, motor oil, not to mention all that yellow snow!

What, I’m sure you are asking, does biochar have to do with any of this? I have an answer! Or perhaps a breakthrough vision is a better descriptor. (According to Peter Diamontes “The day before something is a breakthrough it’s a crazy idea.” so feel free to call it a crazy idea!)

Imagine this: snow is hauled to a location where tree limbs that have suffered from ice & snow damage are also dumped. Tree debris is chipped for use in a combined heat and biochar (CHAB) unit where the heat can be used to melt the snow. The biochar produced can be used to filter the water so that the water can be returned in a healthier state to the environment. (Note this char is not in a condition to be put in the soil, but there are emerging technologies to remove these impurities.)

Or imagine this: parking lots could have smaller CHAB units which can either run on biomass waste from the various retail or industrial establishments. Snow can be brought to the CHAB area which sits atop some permeable pavement that sits atop a whole lot of biochar so that the melting snow and its various impurities can be filtered before heading down to recharge aquifers.

Or imagine this: communities could have mobile mini CHAB units and locate them near storm drains during winter months. These could run on community green waste (which admittedly would probably need to be pelletized to maximize efficiency). Biochar socks (which Charchimedes and I have dubbed ‘Charsettes’ with a nod to the French word “chaussettes” which means socks) could surround the storm drains to filter out the nasties, leaving much cleaner water for the sewage systems to handle.

And there you have my black and white solutions for snow removal using biochar production!

Paving the way to a more sustainable future

Pavement

The combination of biochar and permeable pavements may just provide a very viable, not to mention green, path to fighting & adapting to climate change. Permeable pavements provide a plethora of economic and environmental benefits over traditional fossil fuel based pavement options such as asphalt. They promote storm water management, erosion control, reduced flooding, water filtration, reduce heat island effect and lower maintenance costs over 20 years. Some such as Ecoraster, can even be snowplowed over which is obviously a big concern in my neck of the woods! These types of pavements can be used for everything from parking lots to paddocks, roads to rooftops, lawns to links and could probably replace things like astroturf with a much healthier alternative.

The love connection between biochar and pavers takes place underground, somewhere between the base and leveling layer (see pic). Base layers are generally filed with gravel, while small stones make up the substrate layer, and soil sits on top in the leveling layer. Depending on where the pavers are being used and if the traffic will be of the two or four legged or wheeled variety, the depth of each of these layers can vary significantly. Suffice to say though that the volume of char and related carbon that could potentially be sequestered under these pavers could be considerable. [If any of you susty engineers out there would like to do a back of the envelope calculation per square foot using biochar with a carbon content of 75%, I’d be very happy to update this post with your findings!]  Beyond the carbon sequestration benefit, there is the not insignificant filtration benefit that biochar brings.  More and more research is showing that biochar can be specifically tweaked to capture different metals or nutrients so depending on where pavements are laid, the char could be customized to deal with specific issues. This would result in groundwater and aquifers receiving fresh filtered water, something which places like California would welcome no doubt!

Buy why stop at merely using the char in the substrates? Right now these pavers are made from recycled plastic, which isn’t a bad thing. But in the not too distant future, it is highly likely that these could be fabricated with a 3D printer using biochar materials, making it even more earth friendly. The biochar-permeable pavement combination may sound like the road less traveled right now, but I predict that as the impacts of climate change descend ever more frequently and forcefully, humanity may well beat a well worn path to the door of permeable pavement and biochar!

Biochar as an Acoustics Insulator

acoustics

Joining random LinkedIn groups does wonders for creative thinking. In my inbox today was a LinkedIn discussion email about the Acoustic Insulation (AI) market, something I have given exactly zero previous thought to in my life. Apparently this market is set to boom (or someone is desperately trying to sell Market Reports) to the tune of $4B in the not too distant future. So of course this got me thinking (about biochar). And googling (about acoustic insulation materials). Could this be the next big avenue B?

Similar to insulation used for temperature control, AI (I confess this acronym bothers me a bit, but only fellow farm folk will probably understand why!) materials are used in walls and ceilings, but also in floors. Typical materials used for AI, include rockwool, fiberglass, cotton and cellulose. How might biochar stack up as a replacement for any of these materials? Well we already know it has been used quite successfully for temperature and humidity control so it’s not a stretch to think that it could work for acoustics as well.

Let’s dig a little deeper into the sustainability of the competition though, shall we? First up is rockwool, made of ‘natural materials’ (i.e. chalk and rock). Sounds all susty, right? Wrong. There is the issue of needing 3000F to turn said solid stuff into something like cotton candy. Embodied energy = 16.8 (energy MJ per kg). Next up is fiberglass made of glass, sand, soda ash, limestone, borax and binder coatings. While its usually one of the cheaper options, it also requires a high energy production process to convert it into fibers. Cotton is up next. Mostly made from recycled jeans, it’s a tad pricey but I’ve used this stuff and it’s great. Cellulose is similar, made from recycled paper but has the added benefit that it can be composted at the end of its life!

Biochar compares nicely from an embodied energy perspective – heck it could even be made on site while building or renovating from leftover construction materials or debris while providing remote energy so it is likely much lower (dare I suggest negative…) on the embodied energy scale. Like cellulose it can be composted at the end of its life.  But I think biochar could go one step further than some of the materials I’ve mentioned.  I suspect biochar insulation could fairly easily be molded into different shapes for optimal silencing or simply sprayed on like a plaster. And then there is that whole topic of carbon sequestration!

I do believe biochar as an acoustic insulation material could be a resounding success!  Who knows where all of this could LEED…