# Unit 5: Heating vs consumption of electrical energy. Energy saving.

Let us analyze more closely how big is the part of electrical energy (and heat energy) consumption from the total energy consumption. For this we analyze the energy consumption of a household during one week. We try to find out how big is a part of a heating, and how big is a part consumed by electrical appliances. As one can see from Problem 4.2, this is different for different months. Also, for different countries. In the summer there is no need for heating in Estonia. But in southern Europe, e.g. in Italy, Greece and Spain in the summer the conditioners are needed. Therefore also the house construction principles are different, and materials, also.

In the following problem we try to analyze the energy consumption by energy types and try to estimate how to find possibilities for energy saving. These options depend on the type of the household (apartment or private house), the number of rooms and area of the walls, etc. To find more possibilities, we assume that the household is a private house, and we consider the energy consumption during one week.

# Problem 5.1

Estimate the energy consumption of a one store private house with 100 m^{2} surface area during 1 week in November, and analyze the energy saving options in your group. You can assume that average interior temperature is 22^{o}C.

For this:

- Find the average air temperature in November (you can use data from Problem 4.1).
- Using the experience from Problems 2.1, 4.1, and 4.2 find: a) total energy consumed by electrical appliances during 1 week; b) heating energy consumed during 1 week. You can copy and use the 2. sheet from the spreadsheet.
- Discuss and analyze in your group how big could be the energy saving if you use the solar panels with 25 m
^{2}area, and for what this electrical energy could be used. - Use the desmos program to find out how to decrease the energy consumption of the household by 10% (e.g. adding a layer of rock wool to the walls, changing the windows, etc).