Big Grower November 2020 - 4

COVER STORY
In the late 1990s, the federal regulations were eliminated so Oxbow
Power no longer needed to have a thermal host for the excess steam. The
utility company eventually lost interest in continuing to maintain the
greenhouse. During this time an increasing amount of vine crop vegetables
were being shipped into the United States from Canada and Mexico.
" The regulations for U.S. power plants went away in the late 1990s so they
no longer needed to have these thermal hosts to operate, " Elfstrum says.
" Oxbow Power eventually shuttered the greenhouses in 2012. Because of
the economics of commodity tomatoes and cucumbers, the power company
could not compete with the imported vegetables coming in from Canada
and Mexico. "
INCREASING OPERATIONAL EFFICIENCY
When Elfstrum and his partners acquired the facility in 2015 they
initially started with vine crops.
" We made an attempt at growing vine crops to compete in the world of
commodity greenhouse crops, " he says. " We had a deal with a local grocery
chain to grow eggplants, English cucumbers and beefsteak tomatoes. We
were trying to market our crops as the locally grown option. "
Because those crop categories are highly commoditized, he says it was
difficult to differentiate their products even though they were locally grown.
Although Elfstrum and his partners wanted to produce commercially
Wheatfield Gardens is producing multiple varieties of hydroponic lettuce,
herbs and auto-flowering hemp cultivars of Cannabis ruderalis.
profitable crops, more importantly they wanted to use the greenhouses as
a proving ground for their own controlled environment technology.
" Some of my partners came from the on-site power industry, specifically
designing microgrids and cogeneration systems is our area of expertise, "
he explains. " We used the greenhouses as an opportunity to demonstrate
our novel patented technology that optimizes the integration of on-site
power production with controlled environment agriculture. Most CEA
farms are very energy intensive. We decided to invest in the power
infrastructure of the facility to make it very efficient.
" We took an aggressive approach at improving our resource efficiency
by using cogeneration and the benefits that come with it, including
generating our own heat and electricity. We have consistent power all the
time because we run the facility with cogeneration. We can also capture
carbon dioxide and deliver it to the plants to increase yields. "
GROWING MORE EFFICIENTLY
While Wheatfield Gardens continues to look for ways to operate more
efficiently, the decision was made to transition away from vine crops to
focus on higher value crops. Lettuce and herbs were added in 2016 and
industrial hemp for cannabidiol (CBD) production began in 2017.
Elfstrum worked with researchers at Cornell University and fellow
industry colleagues from the Greenhouse Lighting and Systems
Engineering (GLASE) consortium to look at alternative crops. Butterhead
lettuce produced in floating rafts became the company's benchmark crop.
The company is also producing multiple varieties of hydroponic lettuce,
herbs and auto-flowering hemp cultivars of Cannabis ruderalis.
" Lettuce travels so far to get to East Coast markets with 90% coming from
the West Coast, " Elfstrum says. " That travel time doesn't make sense. They
are basically trucking water across the U.S. The flavor also suffers during
the long distance transport. "
During the summer Wheatfield Gardens can grow a 300-gram head of
lettuce in 30 days. In winter, the crop time increases to 36 days.
In 2018 Wheatfield Gardens installed Fluence dimmable LEDs that
offered light spectrum control.
" The LEDs allowed us to compete with other lettuce growers and enabled
us to be a consistent supplier to our customers year round, " Elfstrum shares.
" The LEDs were more efficient than high pressure sodium as well as being
dimmable and controllable. That's what we wanted because we are trying
to be as efficient as possible without sacrificing quality. "
The company also recently upgraded its 500-kilowatt transformer from
500 kilovolt-amperes (kVA) to 2,500 kVa so that more LED lights could
be installed.
" We make our own power and carbon dioxide through thermal energy, "
Paal Elfstrum, CEO at Wheatfield Gardens, and his partners want to produce
profitable crops, but also want to use their greenhouses as a proving ground
for their own controlled environment technology.
Elfstrum says. " This is a perfect site to do different research with GLASE,
including lighting, lighting control and supplemental carbon dioxide.
We don't have to worry about power failures because of the grid going
down affecting the studies. Our cogeneration system is backed up with a
400-kilowatt diesel generator. "
4 NOVEMBER 2020
Big Grower November 2020

Table of Contents for the Digital Edition of Big Grower November 2020
