K.K. Pantovic (Serbia)
LCC, MILP, present value, energy savings, optimization
B - fossil-fuel/ electrical central heating boiler,
bj - life span of j equipment (year)
Bj - present value factor for j equipment costs (-)
C - cooker, constant
CADD - additional electricity tariff (€/kWh)
Cl - present value of l variable cost (€)
CH - central heating device
CPV - present value of cost (€)
HDW - individual boiler for domestic hot-water
HE - heat exchanger
HP - heat pump air/air
HS - building envelo
Mixed Integer Linear Programming (MILP) is used for
optimization of global energy system of two-family
residence, located in Kragujevac, Serbia and energy,
equipment and building element prices valid at Serbian
and German market in year 2000.
The mathematical model of global energy system in
residences includes energy demand for space
heating/cooling, cooking, and heating of domestic water,
lighting and running of appliances as well as various types
of energy and equipment to perform energy demands.
Introducing binary coefficients α all practical energy
systems in residences are represented in the mathematical
Mathematical model is linearized and optimized by using
MILP where the objective function is the Life Cycle Cost
(LCC). The scope of investigation includes model
analysis for different types of building elements while
energy and equipment prices are constant. Model is
analyzed for single, double or triple glazed windows,
pearlite, and mineral wool insulation.
At Serbian energy market, high equipment and building
element cost and unbalanced ratio of energy prices have
the greatest influence on selection of optimal energy
system and absence of energy savings.
Use of this model gives optimal investment in building
energy system and steps, which Serbian society must take
over to yield energy savings.