**3.2. Electricity**

**Figure 4** analyzed the potential of total energy demand and produce by this building. Monthly electricity consumption varies between 123.8 and 137.1 kWh.

**Figure 2.** *Monthly indoor air temperature in the new building distributed on three periods (current, 2030 and 2050).*

**9**

**Figure 5.**

**Figure 4.**

*Scenario of Net Zero Energy of building.*

*Application of wind turbine and photovoltaic panel on the building.*

*Net Zero Energy Buildings and Low Carbon Emission, a Case of Study of Madagascar Island*

We can see under basic of this scenario electricity generated by this building corresponds net to electricity consumption; with zero cooling energy building during the different seasons. In the specific case of this scenario, which simply recommends an application of solar panels covering a total area of 182 m2

Energy Building objectives are achieved for this building(energy produce = energy consumption). Electricity generated was estimated to be around of 0.49 kWh/m2

In the second scenario which some results are showed on **Figure 5**, it was applied

It is noticed that in this case, the electricity generated by the building is equal to 13 times the average electricity consumed by the building. At this precise moment of operation of the building, the new building can be considered as a building with positive energy, that is to say it produces more than it consumes (energy consumption < energy produced). The annual total electricity that can be sold to individual consumers is estimated to 18946.86 kWh per year; it allows to save 4550\$. The frequency of comfort and total energy consumption is showed on **Figure 6**.

simultaneously wind turbine and photovoltaic panel on the building.

, Net Zero

.

*DOI: http://dx.doi.org/10.5772/intechopen.90854*

**Figure 3.** *Monthly relative humidity in the new building during three periods (present, 2030 and 2050).*

*Net Zero Energy Buildings and Low Carbon Emission, a Case of Study of Madagascar Island DOI: http://dx.doi.org/10.5772/intechopen.90854*

We can see under basic of this scenario electricity generated by this building corresponds net to electricity consumption; with zero cooling energy building during the different seasons. In the specific case of this scenario, which simply recommends an application of solar panels covering a total area of 182 m2 , Net Zero Energy Building objectives are achieved for this building(energy produce = energy consumption). Electricity generated was estimated to be around of 0.49 kWh/m2 . In the second scenario which some results are showed on **Figure 5**, it was applied simultaneously wind turbine and photovoltaic panel on the building.

It is noticed that in this case, the electricity generated by the building is equal to 13 times the average electricity consumed by the building. At this precise moment of operation of the building, the new building can be considered as a building with positive energy, that is to say it produces more than it consumes (energy consumption < energy produced). The annual total electricity that can be sold to individual consumers is estimated to 18946.86 kWh per year; it allows to save 4550\$. The frequency of comfort and total energy consumption is showed on **Figure 6**.

**Figure 4.** *Scenario of Net Zero Energy of building.*

**Figure 5.** *Application of wind turbine and photovoltaic panel on the building.*

*Zero-Energy Buildings - New Approaches and Technologies*

indoor air temperature is expected to be between 19.96 and 22.82°C; in 2050, in the same condition, indoor air temperature will be between 20.41 and 23.10°C. Globally, indoor air will increase to 0.30°C in 2030, and 0.52°C in 2050; compare to current air temperature. In addition, it is seen in **Figure 3** that presently, relative humidity varies between 59.57 and 75.41%. In the future, it will vary between 58.77 and 76.03% in 2030, and, from 59.82 and 77.25% in 2050. The analysis showed that relative humidity will increase to 1.51% in 2030, and 2.73% in 2050; compare to 2017. The ASHRAE 55 ranges of comfort suggested indoor air temperature of 23–26°C; and relative humidity of 30–60% [25]. These different values are outside the ASHRAE ranges. Antananarivo is dominated by several mountains which affect the climate of this city. This interval is low compare to that found by Nematchoua et al. [26], in

traditional buildings in Madagascar, which were between 24.6 and 28.4°C.

**Figure 4** analyzed the potential of total energy demand and produce by this building. Monthly electricity consumption varies between 123.8 and 137.1 kWh.

*Monthly indoor air temperature in the new building distributed on three periods (current, 2030 and 2050).*

**8**

**Figure 3.**

**Figure 2.**

**3.2. Electricity**

*Monthly relative humidity in the new building during three periods (present, 2030 and 2050).*

**Figure 6.** *Comfort potential and building energy consumption.*

Discomfort potential was estimated to 71.2% (current); 74.4% (2030), and 76.8% (2050). These results show that in 2050, indoor air of the building will be 5.6% more uncomfortable than currently.

It is very important to notice that in specific case of scenario1, energy demand is found at zero. This does not mean that the building does not consume energy, it is just to explain that at this point the energy production is equal to the consumption of the building. The different energy values assigned a sign (−), explain that at this moment there is overproduction. These results are very interesting, and can be used by the building specialists. The electrification rate in Madagascar is one of the lowest in Africa: only 15% of the inhabitants are connected to an electricity grid. This figure rises to 58% in urban areas and drops to 4.7% in rural areas, which nevertheless accounts for 70% of the country's population. It would be recommended to the Malagasy government to create favorable conditions to encourage the population to design new buildings more ecological and comfortable. One of the limitations of this research is that the type of building proposed costs up to 40% more expensive than the more conventional buildings found in the big island. But today, it is revealed in the literature that only 2% of the Malagasy population would be able to build this kind of building. We are well aware of this, but we think that the ideal for a more sustainable solution is to build new buildings in the big island by respecting the criteria mentioned in this study.

#### **4. Conclusion**

In this research, we analyzed and suggested a model allowing to reach net zero energy building and in certain measure created a building with positive energy in Antananarivo. Operational carbon was estimated to be around 3.7 kgCO2/m2 . The operative temperature was between 19 and 23°C, in this period, the comfort potential was from 30%. The results found in this study showed it is possible to reach objective "Net Zero energy building" in Madagascar island by respecting the way detailed in this research. The degree of vulnerability in climate change is very high in Madagascar. The Malagasy government should propose more reliable control and adaptation strategies, for example the case of the extension of ecological buildings is very interesting. In a future study, we will study the case of implementation of the concept Net zero energy neighborhood.

**11**

**Author details**

Fellowships, Paris, France

Modeste Kameni Nematchoua1,2\* and Sigrid Reiter2

2 Management and Analysis (LEMA), Liège, Belgium

provided the original work is properly cited.

1 Beneficiary of an AXA Research Fund Postdoctoral Grant, Research Leaders

\*Address all correspondence to: kameni.modeste@yahoo.fr; mkameni@uliege.be

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

*Net Zero Energy Buildings and Low Carbon Emission, a Case of Study of Madagascar Island*

*DOI: http://dx.doi.org/10.5772/intechopen.90854*

*Net Zero Energy Buildings and Low Carbon Emission, a Case of Study of Madagascar Island DOI: http://dx.doi.org/10.5772/intechopen.90854*
