TY - BOOK
T1 - Visions for future energy efficient district energy systems
AU - Paiho, Satu
AU - Heimonen, Ismo
AU - Grahn, Elina
AU - Abdurafikov, Rinat
AU - Kannari, Lotta
AU - Mikkola, Markku
AU - Ryynänen, Tapani
AU - Laukkanen, Timo
AU - Ypyä, Joel
AU - Kaukonen, Sampo
PY - 2016
Y1 - 2016
N2 - This report gives the vision of the future district
energy systems and describes the state-ofthe art of
district heating related energy systems in Finland. The
challenges and future needs of the energy business and
services are described. The approach for scenario
analyses is presented using the district heating system
of Keski-Uusimaa as a case study. The scenarios of the
energy system selection and energy consumption for the
next 20 years (2015-2035) were presented for the case
study. The scenarios were based on the assumptions of
development scenario of the building stock and energy
efficiency of the buildings. Two different types of
scenario simulations were done. The first one, system
optimization, search for optimal system concept taking
into account the investment costs for the energy
production system including centralized and decentralized
systems. The second one, energy simulation, studied the
influence of the decentralized energy production on the
energy efficiency, emissions and energy costs. Both the
simulation cases had the time frame of 20 years.
The optimization model can be used to study the influence
of production unit costs and external conditions on the
optimal system typology. The energy system optimization
study was based on three main scenarios: the existing bio
CHP plant and gas boiler would be useable during
2015-2035, the CHP plant will be stopped in 2025 or there
are no existing units in the region. The optimization
takes into account costs of the equipment and energy,
external conditions (solar, wind) as well as heating and
power needs. The study of alternatives showed that it is
cost optimal to use the already existing CHP plant. The
heat pumps, gas boilers and wind and gas turbines will
support the energy system when the CHP is not used
anymore.
In the energy simulation study, a set of scenarios for
the development of the case area's district heating
system have been made. The purpose of the scenarios was
not to make a prediction of what the future heating
energy systems will be like, but rather to examine what
different possible development pathways there are and
compare them in terms of technical, environmental and
economic criteria. The conservative, extensive and
extreme scenarios assumed different amounts of solar
energy and ground source heat pumps to be implemented as
decentralized systems (1%, 10% or 50% of floor area
implemented decentralized RES). The industrial heat was
used or the consumer acted as an active prosumer selling
the excess solar heat back to network.
In the case of simulations, the extreme scenario with
ground source heat pumps and a solar thermal system
decreased the annual centralized heat production by 34%
and, in the case of industrial waste heat by 32% at the
end of the scenario timeframe compared to starting year.
The non-renewable heat consumption decreased 46% in case
of industrial waste. In the case where 20% of the
district heating was originating from the industrial
waste heat source, the CO2 emissions decreased by 50%.
The energy costs depend strongly on the scenario
assumptions. The yearly energy costs of reference case
decreased 22% compared to the starting year, and the
biggest reduction (34 %) was gained in the extreme
scenario. In the conservative, extensive and extreme
scenarios using heat pumps, the CO2 emissions increased
compared to the reference case, due to the increase in
electricity use by heat pumps. The case studies showed
that environmental performance depends strongly on the
source of emission factors for the primary energy, e.g.,
if the real factor based on local conditions or average
national values will be used. The energy-saving benefits
of the prosumer scenario were quite small (
AB - This report gives the vision of the future district
energy systems and describes the state-ofthe art of
district heating related energy systems in Finland. The
challenges and future needs of the energy business and
services are described. The approach for scenario
analyses is presented using the district heating system
of Keski-Uusimaa as a case study. The scenarios of the
energy system selection and energy consumption for the
next 20 years (2015-2035) were presented for the case
study. The scenarios were based on the assumptions of
development scenario of the building stock and energy
efficiency of the buildings. Two different types of
scenario simulations were done. The first one, system
optimization, search for optimal system concept taking
into account the investment costs for the energy
production system including centralized and decentralized
systems. The second one, energy simulation, studied the
influence of the decentralized energy production on the
energy efficiency, emissions and energy costs. Both the
simulation cases had the time frame of 20 years.
The optimization model can be used to study the influence
of production unit costs and external conditions on the
optimal system typology. The energy system optimization
study was based on three main scenarios: the existing bio
CHP plant and gas boiler would be useable during
2015-2035, the CHP plant will be stopped in 2025 or there
are no existing units in the region. The optimization
takes into account costs of the equipment and energy,
external conditions (solar, wind) as well as heating and
power needs. The study of alternatives showed that it is
cost optimal to use the already existing CHP plant. The
heat pumps, gas boilers and wind and gas turbines will
support the energy system when the CHP is not used
anymore.
In the energy simulation study, a set of scenarios for
the development of the case area's district heating
system have been made. The purpose of the scenarios was
not to make a prediction of what the future heating
energy systems will be like, but rather to examine what
different possible development pathways there are and
compare them in terms of technical, environmental and
economic criteria. The conservative, extensive and
extreme scenarios assumed different amounts of solar
energy and ground source heat pumps to be implemented as
decentralized systems (1%, 10% or 50% of floor area
implemented decentralized RES). The industrial heat was
used or the consumer acted as an active prosumer selling
the excess solar heat back to network.
In the case of simulations, the extreme scenario with
ground source heat pumps and a solar thermal system
decreased the annual centralized heat production by 34%
and, in the case of industrial waste heat by 32% at the
end of the scenario timeframe compared to starting year.
The non-renewable heat consumption decreased 46% in case
of industrial waste. In the case where 20% of the
district heating was originating from the industrial
waste heat source, the CO2 emissions decreased by 50%.
The energy costs depend strongly on the scenario
assumptions. The yearly energy costs of reference case
decreased 22% compared to the starting year, and the
biggest reduction (34 %) was gained in the extreme
scenario. In the conservative, extensive and extreme
scenarios using heat pumps, the CO2 emissions increased
compared to the reference case, due to the increase in
electricity use by heat pumps. The case studies showed
that environmental performance depends strongly on the
source of emission factors for the primary energy, e.g.,
if the real factor based on local conditions or average
national values will be used. The energy-saving benefits
of the prosumer scenario were quite small (
KW - district energy systems
KW - future
KW - energy efficiency
M3 - Report
T3 - VTT Technology
BT - Visions for future energy efficient district energy systems
PB - VTT Technical Research Centre of Finland
ER -
