Aim of the case study
The aim of the study is to find the direction of potential development of the site in terms of renovation of existing buildings, construction of new buildings and way of energy needs cover in accordance with the principles of energy efficient and sustainable construction.
Emissions of carbon dioxide (or achieving a state that is known as ZERO-CARBON) was chosen as an indicator of sustainable development, in line with the European project, which is part of the study.
Scale of the study
As a pilot phase, part of the area known as Brno Bronx, has been selected. During this phase a computer model was created and solutions were found. It is a very diverse, densely built-up urban area in the city. The location is suitable as a model case because it includes many ways of building usage and types of energy consumption.
In the initial phase of the study current energy consumption of area and its structures was calculated with regard to the building usage profiles – housing, administration, production, etc. The calculating process was not based on measured values, which are not suitable for this purpose, but the so-called typical usage of buildings.
Existing energy consumption is not exceptional in terms of energy performance where exists large dispersion from neglected, brick, not insulated buildings to nearly new building or building insulation after complete reconstruction. In the area there are no buildings that would have low energy or passive standard with premium thermal and technical characteristics and advanced technologies.
The area contains production buildings (bakeries), with significantly different pattern of consumption – high heat consumption in technology.
The area also includes a large historical building, which is used limited and it´s connected to project Creative Centre Brno.
The area is connected to system of district heating but coverage is not too high –app 27 % of total consumption. The boiler room or house local heaters to natural gas are most present.
The calculation of the initial phase also took into account the parameters of the district heating system – distribution losses, source production efficiency, etc. Sources of district heating predominantly burn natural gas, with a certain percentage covered from municipal waste incineration.
A considerable reduction in energy consumption was achieved thanks to both structural measures such as building insulation and increasing the efficiency of energy production and distribution. As part of the study, specific measures were proposed leading to energy savings and expected benefits were calculated for individual consumption rates – heating, water heating, cooling, lighting, etc.
Possibilities for supplying the site with renewable energy sources with low or no carbon dioxide emissions were addressed. The primary preference was producing energy locally through renewable resources – solar collectors and panels were proposed for heating water and producing electricity. The possibilities for producing energy from renewable resources in the area are relatively limited.
The solution chosen was connecting the remaining buildings to the district heating system, which in the future will allow for a greater volume of burning wood chips or straw and simultaneous combined production of electricity and heat.
A ZERO-CARBON state was achieved by offsetting the residual CO2 production in the heating plant sources via the electricity produced in co-generation. The result is a zero carbon balance for the area as a whole from the perspective of all energy needs (see accompanying graph).