Review Of Low/Zero Carbon Design Technology And Implementation Of Net Zero Energy Homes

Selection of Construction Materials that are Low in Carbon

A Net-Zero Energy house is referred to as a house that produces as much energy as it uses from the grid by utilizing renewable energy sources. Many countries around the world have started to adopt this kind of a technology so as to improve energy efficiency in the residential houses. For a building or a house to be considered as zero energy there have to be no emissions of carbon from the processes that are taking place inside the building (Alhorr, Eliskandarani, & Elsarrag, 2014). Carbon emission nowadays is always be considered as a threat to the environment and therefore every precaution should be taken to ensure that carbon emission to the environment is minimized.

This paper mainly focuses on the upgrade of a house that is not zero-energy into a redesigned house that fulfills the requirements of a Net zero energy home and to achieve this serious consideration should be given to the materials, water consumption and using on-site renewable energy wastes. Therefore while designing a net zero carbon emission house the whole life cycle should focus on the environment to ensure that little or no carbon is emitted.

For the purposes of achieving a Net Zero building, the focus should be directed to the selection of building materials. The materials may include cement, building blocks, steel and many others. The materials delivered to the construction site should be checked for carbon emissions. This should be done both in the production areas and during the delivery of the materials at the construction site (Giesekam, Barrett, & Taylor, 2015). The designer of the building should select only the materials that have got little or no emissions of carbon. The materials selected should also be checked whether they can be recycled. The materials should not have a negative impact on human health.

There are several requirements that must be met when selecting the materials used for the construction of the net zero energy buildings. These requirements include;

1. The process of production should be as simple as possible because complex processes will eventually consume a lot of energy hence the carbon emission will be more.
2. Minimum waste of the materials during construction.
3. Mechanical properties for structural materials such as stiffness, strength in case there is a seismic action
4. The distance between the production site and the construction should be as minimum as possible to ensure there is less carbon emission.
5. The material should be recyclable and should be from a renewable source.

There are various materials that have been known to emit low carbon during their production. These include;

1. Timber or wood- Timber emits very low carbon and consumes low energy during its production. Timber is also light to handle and is comprised of several layers therefore making it more stable. Due to these factors, timber is ideal for constructing buildings that are Net zero energy (Brady, 2016).
2. Rock wool; This is an insulation product that is preferred because of its durability, thermal performance and fire protection. The rock wool is produced from mineral wool and contains fine fiber. It is produced from renewable rocks from volcanic and it saves a lot of energy. Changes in temperature and humidity do not affect the rock wool because it doesn’t corrode.
3. Aerated concrete- These are porous materials which are light in weight. Its light weight makes it resistant to high temperatures.

There have been numerous advanced and innovative construction techniques that have been developed to reduce the amount of carbon emitted during construction of buildings. These techniques have been developed with an idea of net-zero energy buildings in mind. Some of these techniques include;

1. Thermal insulation materials- According to Attia et al., (2015), better materials have been developed which are able to minimize the heating and cooling of the house. Double glazed and triple glazed windows have now replaced the single glazed windows. This helps to save energy consumption by use of active ventilation and heat recovery process.
2. Precast construction methods- This has been done by reducing the onsite construction waste and carbon emissions. The waste is casted and later relocated
3. Passive solar and radiant heating- This involves diverting the sunlight in the different areas of a building to increase the temperature in the winter season and in the summer season the breeze is diverted into internal areas so as to lower the internal temperature.
4. Installation of solar energy- This involves the installation of solar energy by installing the solar panels and solar water heaters (“Net zero energy building design fundamentals,” 2017).

Other approaches include lowering the demand for building energy through enabling the sealing and insulation capabilities by incorporating the use of enhanced construction materials such as shading and thermal insulation among others. During the sustainable passive designing, the aspect of site and layout planning, natural ventilation and lighting should be considered and incorporated. These reduce the energy consumption (Attia, 2018).

In the management of energy consumption, the main aim is to reduce the energy consumed and at the same time improve energy efficiency. This will involve checking regularly and controlling the energy consumption. This is normally done by recording and implementing policies that meet the energy efficiency goals in the construction sector. Considerable administration of policies needs to employ tactics that will lower the amount of energy consumed so as to make the environment efficient (Gram-Hanssen, 2012). In the construction sector, the materials requiring high capital should be used last. Renewable sources of energy should be used and the equipment used should be energy efficient.

Innovative Process during Construction

There are other ways that can be used to manage energy consumption such as designing a house with enough natural lighting during the day. There should be some trees surrounding the building because they can absorb the carbon dioxide that is emitted when appliances are used inside the buildings.

Renewable energy is obtained from sources which are replenished naturally. The energy sources are explained below;

During construction, the solar energy is converted into heat energy by use of a solar water heater. This heat energy then converts into electric energy by using photo voltaic cells. The cells acquire the sunlight transferring electrons and finally forming a charge which is stored as electricity. This technology is efficient because it doesn’t involve the burning of the fuel. Solar energy is until now the biggest form of renewable energy and its use is all over the world (Newton, 2017).

Wind energy is converted into electrical energy through the use of wind turbines and batteries which store the energy produced. Turbines get rotated by the wind energy which is converted into a torque on rotor blades. In farming, wind energy is used for water pumping and in residential areas it is used to charge batteries.

Biomass is the mixer of organic material that is obtained from animals and plants. This produces a bio-fuel known as biogas and the waste is dry or wet and can be utilized as fertilizer for the plants.

This is the energy that is produced by the warmth of the earth. The sources for this energy include hot water and hot rocks located down the earth’s surface (McNabb, 2013). It is known to produce electrical energy.

Flow of water is used to produce the hydro energy which then produces electricity.

Natural resources are normally recycled to limit contamination, reduce usage of water and energy and decrease temperature modification. Some of the materials that are recycled include;

Timber recovered from demolition waste can be re-utilized and be of much help in another construction site or to manufacture some other products

In cases of buildings demolitions, used metals are produced and can be reused and it has been discovered that the reused steel generates less carbon compared to new manufacturing of steel.

We have debated the benefits achieved by converting our traditional home into a “Net Zero Energy” home.  The procedure is easy to implement as it lowers the carbon emissions as well and the home will be energy efficient (Fong & Lee, 2012).The same procedure should be used for the construction of all new building structures so that they will be energy efficient, cost effective and sustainable to the environment as well.

The process of implementing low carbon emission materials and net zero energy process has a high initial investment and people tend to avoid the high initial cost processes.

Conclusion

In order to lower the energy consumption, changes are made in the selection of materials and appliances used and adopt the use of materials and construction process that are emitting carbon (Albadry, Sewilam, & Tarabieh, 2016). The net-zero energy homes usually combine the construction design that is efficient, appliances that are energy efficient, passive solar energy that is integrated with commercially available renewable energy systems with the goal of achieving a net-zero energy use on an annual basis. The RH that incorporate net-zero energy use considerably reduce the greenhouse gas production (Loftness, 2013). By using the energy efficient concept integrated with renewable energy technology, homeowners are therefore able to reduce their energy costs and requirements. They are therefore able to bring a sustainable solution for the long-run towards the reduction of greenhouse gas and other emissions that are responsible for global warming.

References

Albadry, S., Sewilam, H. and Tarabieh, K. 2016. Feasibility of Converting Existing Residential Buildings to Net Zero-Energy Buildings in Egypt.

Alhorr, Y., Eliskandarani, E. & Elsarrag, E. 2014. Approaches to reducing carbon dioxide emissions in the built environment: Low carbon cities. International Journal of Sustainable Built Environment, 3(2), 167-178.

Attia, S., 2018. Net Zero Energy Buildings Performance Indicators and Thresholds. Net Zero Energy Buildings (NZEB), 53-85.

Attia, S., Hamdy, M., Carlucci, S., Pagliano, L., Bucking, S., & Hasan, A. 2015. Building performance optimization of net zero-energy buildings. Modeling, Design, and Optimization of Net-Zero Energy Buildings, 175-206.

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