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Nexterra's gasification process will turn waste wood such as tree trimmings into a combustible fuel called syngas. (CBC)

New biomass generating technology will be installed at the University of British Columbia to convert tree trimmings from Vancouver residents into heat and electricity.

A biomass system built by Vancouver-based Nexterra Systems Corp. will begin operating at the university's Vancouver campus in late 2011, the company announced Tuesday after finalizing the agreement with the school.

The system is the first in North America to turn biomass into a combustible gas fed into an internal combustion engine. The process has higher efficiency and lower water consumption than conventional biomass generation based on a steam cycle, said company spokesman Darcy Quinn in an email.

According to Harvie Campbell, chair of the Clean Power Association of BC, the system is 50 per cent more fuel efficient than conventional biomass power plants.

Quinn said the process makes biomass power more feasible on a small scale, allowing for plants that produce 10 megawatts of electricity or less. 

Nexterra's technology converts wood waste into a combustible fuel called syngas, which is typically a mixture of carbon monoxide and hydrogen, with some ash left behind. That fuel will be used in a gas engine made by General Electric to produce two megawatts of electricity. The waste heat will generate steam that is expected to offset about 15 per cent of the natural gas currently used for heating at UBC.

Emissions to be cut 4,000 tonnes a year

The university's greenhouse gas emissions are expected to be reduced by 4,000 tonnes per year.

Nexterra's website said the system's main advantage is that the syngas produced is "exceptionally" clean, with very low emissions of particulates like soot. That means pollution control equipment may not need to be installed with the system.

The City of Vancouver and local companies will provide the tree trimmings and other wood waste to fuel the system.

Jonathan Rhone, CEO of Nexterra, said the deal was a big milestone for the company.

"And the agreement clearly signals UBC's intention to become a leading centre for commercialization of clean energy technologies," he added.

Nexterra's system is what is known as a fixed-bed, updraft gasifier. Fuel is fed into a dome-shaped container at a controlled rate. A carefully portioned mixture of air, steam and/or oxygen enters at the base of the fuel pile and the temperature of the system is carefully managed to control the gas production.