Structural Design of the mCCHP-RES System - Design for Micro-Combined Cooling, Heating and Power Systems - page 162

In the next steps, these structural models will be concretized and comparatively
analyzed. The ultimate goal of analysis is to obtain an optimal trade-off between the
performance indicators and investment cost. Finally, one of these models will be
selected to be applied practically.

5 Consumption Estimation

Consumption means the form and quantity of energy consumed in a time unit.
Depending on the time unit, the consumption may be annual, monthly, or daily.
Firstly, the consumption may be estimated either at consumer (end-use) level, or
at residence level.
At residence level, consumption may be global or speci

c. Consumption is
global when it refers to the whole residence. If the global consumption is divided to
the total c.

Moreover, the consumption is estimated for each form of energy consumed and
each function of the residence covered. For example, the forms of energy considered
could be heat and power, while the residence functions covered could be heating, air
conditioning, hot water, and domestic facilities. Evaluating of the residence con-
sumption based on the energy form is called consumption aggregating.
Understanding energy uses in the buildings sector is complex because of lack of
reliable data on the energy consumption by end-use (e.g., heating, cooling, lighting,
IT equipment and appliances), and because of the large variety of building cate-
gories in this sector. Subdivision of energy consumption can be particularly dif

floor area (TFA) of the residence building, then it becomes speci

cult
in the cases of electricity, where air-conditioners, appliances, lights, pumps, and
heating installations all draw electricity and often from the same metering. In
residential buildings, the installed equipment and appliances require electrical
energy, as do removable devices like mobile phone chargers, laptops, and electric
cars in the future. However, identi cation of xed and fluctuating demand for

electrical energy rarely appears in a building s consumption metric, as single

measurement consider only the total amount consumed by the whole building.
Natural gas, too, can serve several end uses at once, including heating, cooking, and
the provision of domestic hot water. The typically amount of energy required in the
residential buildings and the percent of total energy need is illustrated in Fig. 10 .
Given the dif

'

energy requirements and the use of
different fuel types, most analysis examines energy use in building as de

culty in subdividing buildings '

ned by
end-use: space heating, cooling, cooking, etc. The split in use of energy will be less
accurate due to uncertainties, and it will vary with different types of buildings and
also with the age and use of the buildings.
The importance of consumption for space heating and cooling varies by country
and region depending on climate. Most energy in the building sector is used for
space and water heating, while the energy consumption for cooling is generally
modest. In hot countries, with little or no space heating needs, cooling is much more
important.