POWER May 2015 - 43

GENERATION TRANSITIONS
1. From lab to plant. These U.S. Water Services research and development scientists are
testing water. The company offers customized water services to power producers that integrate
equipment and chemistry components. Courtesy: U.S. Water Services Inc.
" Until the 1930s, " noted Rudeck, " the company's
generation was 100% hydro, " as the
company is located in an area rich with water
resources.
In those early days, " red ore, " or hematite,
was the chief mineral product of the utility's
iron ore customers. After World War II, hematite
reserves began to dwindle. The iron
industry turned to taconite ore (rich in magnetite),
where coal-fired generation was able
to provide the larger amounts of baseload
electricity required for taconite mining, pelletizing,
and shipping.
The utility's website says, " Minnesota
Power prospered during the years before
and after World War II with the expansion
of iron ore mining, forestry/paper
industries, grain exports and shipbuilding
on Lake Superior. Power plants, including
Laskin Energy Center, Taconite Harbor Energy
Center and Boswell, were built during
the 1950s through the 1970s to help accommodate
an increasing industrial load. "
All were coal-fired plants.
By 2006, said Minnesota Power's Rudeck,
cash out its profitable investment in the fastgrowing
company. " ALLETE was ideal for
us, " U.S. Water's LaMarr Barnes, vice president
for marketing and strategy, told POWER.
" It is a related industry, and believes strongly
in the energy and water nexus. " In addition,
he said, ALLETE has access to relatively
low-cost capital to fuel the water company's
projected growth.
U.S. Water's business strength is an integrated
approach to water management,
said Kent Herbst, vice president for equipment
and engineering services. Herbst said
the major approach of the company is offering
a complete solution for the needs of
the customer (Figure 1). Traditionally, he
noted, " Firms in the water business offered
off-the-shelf approaches, some chemical,
some equipment-based, " that might not work
together. U.S. Water offers tailored solutions
" combined under the same roof. "
Since its founding in 1997, when it initially
focused on ethanol producers, U.S. Water
has seen extraordinary growth, both through
acquisitions and in its basic business. The
company has experienced up to 30% annual
growth since its founding, and has never seen
a year with less than 20% growth, the company
said. Now it is transitioning to a new
business environment, owned by a company
with a diverse, although mostly energy-related,
line of businesses. Barnes said, " We expect
to continue on a similar growth path, "
focusing on markets including oil and gas
mid-stream businesses, food and beverage
firms, power generation (see sidebar), biofuels
(primarily ethanol), and commercial and
institutional customers.
May 2015 | POWER
Fuels Transition
Then there is ALLETE's power generation
transition. Al Rudeck, Minnesota Power's
vice president for power strategy and planning,
said in a POWER interview that power
generation transition is a major element in the
company's history and its future. The utility
began at the beginning of the 20th century as
Duluth Edison Electric Co., in a heavily forested
territory that was rich in minerals.
At the end of World War I, the company
acquired several neighboring utilities and
emerged as Minnesota Power and Light.
" We were 97% coal. " At that point, assessing
the evolving economic and policy environment
and the need to meet the state's requirements
for renewable energy, the company
began a strategic move to diversify its generating
mix.
The latest generation transition moves
away from coal and toward gas and renewables,
primarily wind. While still relying on
the muscular 1,000 MW from its four-unit
Boswell coal-fired station, Minnesota Power
has scaled back its take from the Milton
Young plant, owned by Square Butte CoopManaging
Cooling Tower Phosphorus Discharge
One of the water quality challenges facing
steam-electric generating plants is phosphorus
discharge from closed-cycle cooling
towers. Phosphorous is a biological
nutrient that can cause severe impacts,
such as algal blooms in rivers, lakes, and
estuaries. According to U.S. Water Service's
LaMarr Barnes, states are ratcheting down
on phosphorus discharges. Wisconsin, in
particular, is adopting rules limiting discharges
to " very close to the minimum
detectable levels. "
This is a problem for power plants with
closed-cycle cooling towers. " Everybody
has phosphorus in their water chemistry "
for cooling towers, Barnes said. Power
plant operators widely use phosphorus
chemistry to prevent mineral scale buildup
in the cooling towers and corrosion.
www.powermag.com
Scale decreases the efficiency of the cooling
tower, and corrosion eats into the life
of the equipment. What to do?
U.S. Water has developed what it claims
is a cost-effective alternative to phosphorus
chemistry for protecting power plant
cooling systems, called " Phos Zero. " In
an interview with POWER Associate Editor
Aaron Larson (see http://bit.ly/1xfAXNu),
Barnes said his company's new cooling
water chemistry " has no phosphorus in
it, and it provides equivalent and better
protection compared to a stabilized phosophate
cooling water program or an allorganic
phosphate program. "
U.S. Water is working with a major coalfired
plant in Springfield, Ill., to demonstrate
the commercialization of its Phos
Zero technology.
43

http://www.bit.ly/1xfAXNu http://www.powermag.com

POWER May 2015

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