Jerusalem artichokes and empress trees - new crops with potential

Monday, January 2, 2012

Though they are barely at the starting gate in Ontario, both show promise if market demand for biofuels continues to grow. But both also need processors to get them off the ground

by MIKE MULHERN

Larry Whetstone's business is selling inulin, a type of sugar derived from chicory crops in Europe, but he'd rather be selling inulin produced from Jerusalem artichoke crops in North America.

Whetstone, who lives in Duncan, B.C., is a big Jerusalem artichoke advocate. He says it would be a great crop for Ontario's sand plains. It would be better than corn for biofuel production and one planting would get you four to five years of stem yield before you have to harvest the tubers. And they could be used for biofuels with the pulp going to pig feed.

Robert Smale, who lives near Mossley, is a big fan of a sterile variety of empress trees cloned in the United States. He believes they have great potential as a carbon credit vehicle, but they are also prolific hardwood producers. A tree matures to a height of 16 feet and 16 inches in diameter in 10 or 12 years. The hardwood can be used for furniture or it can be ground up and pelleted for use as a fuel. Once the tree is cut down, a new tree springs from the stump and that happens up to seven times.

That's probably a good thing when you consider that Smale sells small trees for $37, going to $40 or $45 for larger ones. Having Smale come out and do a planting for you costs $50 a tree. A one-acre plantation, he says, would cost about $16,500.

What these two crops have in common is that they are new, at least in Ontario, and they both need market infrastructure, probably in the form of a processor, before they can be considered on any scale.

The empress tree is pretty straightforward. It's sterile, so it can't become invasive like its cousin the tomentosa/princess, which Smale describes as the black sheep of the Paulownia tree family.  The tomentosa is invasive in the United States and is not allowed into Canada.

For anyone planting the empress, the revenue stream could include international carbon credits or Canadian credits, if and when they are traded. Smale, who has been in the empress business three years, has 1,200 planted near Mossley and says there are about 8,000 more growing across the country.

Smale hopes the market will grow through demand for biofuels, possibly as a replacement for coal at Ontario's coal-fired generation stations. If that doesn't happen, there are world markets to consider. He points to a study by the Canadian arm of PricewaterhouseCoopers (PwC) which says global demand for wood fibre will outpace production in the next 10 years, even considering the drop in demand for newsprint.

Smale hopes some of that wood fibre demand will boost the market for his fast-growing trees.

The Jerusalem artichoke, which is actually a sunflower, has a few champions and there is research being done in Ontario which could lead to something more if all the stars align, including demand for food, feed or fuel industries. Fuel possibilities include ethanol, butanol and jet fuel.

Franco Berruti, a professor in the faculty of engineering in the department of chemical and biochemical engineering at the University of Western Ontario (UWO), is researching Jerusalem artichoke. The Institute for Chemicals and Fuels for Alternative Resources (ICFAR), created by a number of UWO professors, including Berruti, received a $150,000 grant this spring to investigate possible uses for the plant. The money came from the Sand Plains Community Development Fund, a federal program intended for projects to aid growth in rural Brant, Elgin, Middlesex, Norfolk and Oxford counties.

Berruti says tubers grown by the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) are being tested and plant and tuber growth from plots his group planted this spring is also being evaluated.

"The interesting part," Berruti says, "is that the tuber doesn't contain starch material as many other plants do but it does contain a sugar. We believe there is a big advantage there, because you don't need the enzymes to break the starch into sugars for making it accessible to the yeast or bacteria."

That makes it ideal for both ethanol and butanol production, but Berruti is concentrating on butanol.

"It (butanol) has a much higher caloric value and it's not corrosive. Ethanol is a really bad fuel," he says. "Butanol has almost the same caloric value as gasoline, so when you fill up the tank with butanol, you can go as far as you can go with a gasoline tank. With ethanol, you can go about half way." While butanol can be produced from Jerusalem artichoke, it can also be produced from corn and other forms of biomass.

Berruti says his research will also explore other chemicals derived from the Jerusalem artichoke. "It has uses as a food, some pharmaceutical properties, so we are looking at high-value chemicals that could be there or at high-value chemicals that could be derived from the sugars by going through some simple transformations."

People in the ethanol business are looking at butanol production, Berruti says, for a number of reasons, including the fact that butanol production utilizes more of the plant sugars than ethanol production.

You can make butanol from sugars that are used to make ethanol, Berruti says, "but also from sugars that cannot produce ethanol," meaning more of the plant can be used in the process.

"Basically, when you try to make ethanol, you are using only one-third of the plant, and when you make butanol, you are using two-thirds,"Berruti says. His research is due to be completed by March 2012.

Jim Todd, transition crop specialist with OMAFRA, says Jerusalem artichoke has been grown in trials at the Simcoe Research Station and he sees potential for the crop if what he calls "a broad market stream" can be created. 

OMAFRA trials show that upper shoot growth, which can be three metres tall, produces five to 10 tonnes per hectare which can be used as a biomass. Depending on harvest time, the upper growth contains inulin, too.

"Then," Todd says, "you can use the tuber, extract the inulin and use that as a dietary supplement or for making ethanol or bioplastics. And you can use leftover pulp to feed hogs and then use the hog manure to feed anaerobic digesters." BF