www.PowerEngineeringInt.com 29 Power Engineering International February 2018
Electric actuators in
biomass power plants
With the Paris Agreement
signed by 174 countries, there is
a growing focus on renewable
energy, including biomass.
Gerda Nölp looks at the
potentials and challenges for
electric actuators in biomass-
fired power plants
Biomass-fired power plants are becoming increasingly popular, especially in Scandinavian countries, but also in other
regions of the world that are striving to reduce
their carbon dioxide emissions.
A wide range of recent projects shows that
the technology to run these plants economically
is available today, making them a viable
alternative to fossil-fueled plants.
Biomass plants can use various kinds of
organic matter as fuel: usually waste or by-products that are available locally in large
quantities. Combinations of different types of
biomass, natural gas and biomass, or coal and
biomass are also possible.
European biomass power plants frequently
burn straw – a by-product of agriculture – or
wood in various forms such as wood chips,
pellets or other wood waste. In other regions,
other materials such as corn waste, sugar cane
bagasse or oil palm residues are often used.
The basic design and operation of a
biomass plant are almost identical to those of
a coal-fired plant. Converting an existing coal
power station to biomass is possible with
reasonable effort, as numerous examples
Apart from the fuel itself, the main differences
between biomass and fossil-fuel plants lie in
the way the fuel is transported, the grates and
ash handling systems, and the boiler design.
Because biomass is generally coarser than
pulverized coal, for example, biomass boilers
have to be comparatively tall to allow a longer
time for complete combustion.
Most biomass-fired power plants are
combined heat and power facilities that
produce heat for district heating as well as
electricity. Their total efficiency is typically much
higher than that of plants producing only
Valves and valve actuators are key
Denmark’s biomass-fired Skaerbaek CHP plant