ElectraTherm technology generates power from wood waste

ElectraTherm, a leader in distributed, waste heat to power
generation, commissioned its second Green Machine at an integrated wood
products mill in Wallowa, Oregon. Together, the two machines operate off
the waste heat of a biomass boiler to generate emission-free
electricity.

Integrated Biomass Resources processes small-diameter timber into
various wood products, such as firewood and fence posts. Wallowa
Resources Community Solutions Inc. purchased and installed the first
Green Machine at the Wallowa mill in December 2012. The site uses
residuals from its wood products to fuel a Uniconfort dual stage
gasification boiler, creating hot water for process heat used for
drying. The excess heat in the form of hot water is used to fuel the two
Green Machines for onsite power generation. Since the commissioning of
the second machine in July, both Green Machines now operate in tandem
with the biomass boiler. The boiler sends hot water to the Green
Machines at 205°F, which generates a combined output of more than 65 kWe
net for the site. The added electrical generation capacity allows IBR
to offset a greater portion of the electrical demand at the mill, which
displaces the retail cost of power for significant savings. Future plans
to increase efficiency include recovering the heat not utilized by the
Green Machines for additional drying use.

“The Green Machine was easy to incorporate into our system and the
installation and commissioning process went smoothly,” said Matt King,
renewable energy program coordinator, WRCSI. “ElectraTherm provided
strong support during the commissioning process and initial start-up
phase.”

Each Green Machine 4400, ElectraTherm’s standard Organic Rankine
Cycle generator with electrical output up to 65kWe per machine, feeds
off the hot water from the boiler to generate green energy from heat
that would otherwise go to waste. Hot water enters the Green Machines at
up 240 degrees Fahrenhight, where it heats a working fluid into
pressurized vapor. As the vapor expands, it drives ElectraTherm’s
patented twin screw power block, which spins an electric generator and
produces power.

ElectraTherm’s Green Machine generates fuel-free, emission-free power
from low temperature waste heat, on applications such as internal
combustion engines, biomass, geothermal/co-produced fluids and solar
thermal. ElectraTherm’s Green Machine fleet of 42 global installations
has accrued more than 250,000 hours (28 years) of runtime to date. A
list of reference sites is currently available on the website.