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Biochar venture a modern take on an ancient idea

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copyright the Chronicle January 31, 2018


BARTON — A local trio hopes they’ve found a way to fight climate change, clean up Vermont’s water, and create a business at the same time.

Richard and Donna Pion, and longtime friend Luke Persons, have teamed up to turn wood chips into a special type of charcoal called biochar. Their new company is called Green State Biochar.

Biochar is made by heating plant and animal wastes in a kiln with little or no oxygen, a process called pyrolysis.

As the materials heat, they blacken and crystallize, destroying most contaminants, and sealing the others, like heavy metals, into an inert form.

It’s being touted as a major tool for fighting climate change. Because biochar effectively locks carbon away, biochar producers can potentially sell carbon offsets or trade on the carbon market.

Trees and plants pull carbon out of the air and lock it away in their tissues. And because animals eat plants, their bodies and their manure are also rich in carbon.

When plants and animals die, the carbon is released back into the air as they decompose.

The cycle is neutral, because carbon is taken up by a new generation of plants as they grow.

But getting rid of the extra carbon put into the air by burning fossil fuels is challenging. Biochar actually subtracts carbon from the total on the earth’s balance sheet by locking it away in an inert form.

The finished biochar makes a fabulous soil conditioner. People in the Amazon basin made biochar in covered trenches and dug it into the earth for centuries to turn barren shallow rainforest soils into a deep rich loam called terra preta, or beautiful earth. Some of the terra preta is more than 500 years old.

In South America, entrepreneurs are digging up centuries-old terra preta and selling it to farmers and city dwellers for their gardens. In this country boxed or bagged modern biochar sells for as much as $20 a gallon online.

There’s also a lot of research to show that adding biochar to methane digesters, like the ones used in Vermont to turn dairy waste into electricity, greatly increases their efficiency.

And like other kinds of charcoal, biochar can be used to filter water.

That’s what the trio of Barton entrepreneurs hopes to do.

“A couple of years ago, Roger and I were sitting around trying to come up with an idea for a new business,” Ms. Pion said.

“We’re passionate about lakes and streams, and we came up with an idea that would both fight climate change and help clean up our state’s waterways.”

Behind her, as she sits at the desk in her home office, is a view across Crystal Lake.

The couple’s house is right on the water, showing a blank garage wall to Route 5, and stretching back to the shore.

Oversized glass windows frame a sweeping view of the frozen lake and the black icy cliffs on the other side.

Green State Biochar designs and sells systems that use biochar to filter anything from detergent-laden wash water used to clean milking equipment, to the runoff from manure pits.

“I’m passionate about clean water,” Ms. Pion says.

Since a lot of farmers can’t afford the cost of the filters, she spends her weekends writing grants that will help with the costs.

And she’s been meeting with state officials to talk about using biochar filters to filter toxic blue-green algae out of lake water — or keep nutrients out of lakes in the first place.

“Biochar is still new to the people from the Agency of Agriculture,” she said.

And that’s on top of her day job with Vermont Natural Coatings.

Since Act 64, Vermont’s clean water act, was passed, there’s been a lot of interest in figuring out new ways to keep pollution out of the state’s water.

And biochar offers a lot of possibilities.

For example, a trench can be dug along the edge of a field and filled with biochar, filtering runoff water even before it gets to the now-required riparian buffer zone.

Or town road departments can add layers of biochar to roadside ditches or catch basins to catch the pollutants in road runoff.

“When it’s collected all it can hold, they can just dig it up with machinery they already own, and put down new biochar,” Ms. Pion said.

“And we send the old stuff back through the pyrolizer.”

The trapped manure or algae becomes part of the next batch of biochar, while the heat of the kiln destroys contaminants like chemicals, hormones, and drugs.

If chemicals aren’t a concern, biochar laced with manure or other organic material can just be buried underground, deep enough that it won’t be disturbed, but within reach of plant roots.

Elsewhere, it’s being mixed with food waste and chicken litter to create a rich organic base for growing plant crops.

But a small new business needs to pick a single focus, and the Pions and their partner, Mr. Persons, have chosen to work on keeping runoff out of lakes and streams.

Pyrolysis, the process that turns plant and animal materials into biochar, isn’t quite the same as burning. Because it happens without oxygen, it’s closer to decomposition than combustion.

It’s the same process used in wood gasification plants, which release the gases in wood and burn them at high temperatures to produce electricity. Burlington gets its power from a wood chip gasification plant.

And in Tennessee, there’s a project that uses pyrolysis to generate power from landfill waste. It powers 400 homes, while reducing 20 tons of trash into a compact single ton of charcoal.

Locally, the Craftsbury Outdoor Center relies on two wood gasification boilers to heat its central buildings. They’re about four times more efficient than ordinary wood stoves or furnaces.

Pyrolysis can neutralize hormones, drugs, and organic compounds — even toxic ones, like the polychlorinated biphenyls (PCBs) that nearly destroyed a Michigan dairy community 30 years ago after fire retardant was accidentally mixed into cattle feed.

Even heavy metals can be sealed for centuries inside the charcoal.

The Pions’ homemade kiln doesn’t make electricity like commercial models.

“That’s our goal with our next kiln,” Ms. Pion said.

But the company already uses the extra heat the kiln produces to dry the chips before they get to the pyrolizer.

The pyrolizer itself takes almost no energy to run. Once the fire gets going, it feeds on itself.

The homemade kiln, located on a property in Greensboro, is about half the size of her home office, Ms. Pion said, perhaps ten by twelve feet.

It’s the product of a lot of experimentation by Mr. Persons using salvaged materials, and a combination of advice from places like Cornell and Texas A&M that are developing biochar projects, and do-it-yourself knowhow gleaned off the internet.

“Luke can fix or build anything,” Ms. Pion said.

The result is a workable pyrolizer that can kick out about 300 pounds of biochar a day.

“We could put on a second shift and make 600 pounds a day,” Ms. Pion said.

She compares that to state of the art pyrolizers that can produce as much as a ton of biochar per hour and cost a $1-million or more.

“They can spread out over several acres,” she said.

Green State Biochar isn’t quite that ambitious.

But a new pyrolizer is definitely in the works.

“We’re right on the cusp of expanding,” Ms. Pion said. “We have investors, we’re just waiting for the right time.”

She has visions of opening a stump and scrap lumber dump at the new site. Contractors and other businesses would pay to get rid of the very materials that would be turned into biochar.

“One of our goals is to create good-paying jobs for people in the area,” she said. “So we have to figure out innovative ways to increase the revenue stream.”

The company will also be buying sustainably harvested local wood that isn’t suited for lumber.

Worldwide, there’s a huge amount of interest in biochar, Ms. Pion said.

“It’s huge,” she said. “How could I not have heard of this?”

But the tide is turning.

“I really believe that in five or six years, nobody will be asking what’s biochar,” she said.

contact Elizabeth Trail at

[email protected]

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