Archive for category Sustainable Design
Eco House Design | Conclusion | Part 10
Posted by BenzuJK in Architecture, Design Guide, House Design, Sustainable Design on June 4, 2017
Eco House Design | Conclusion
The project has been designed using an integrated system of Passivhaus technique developed in Germany in 1990 and Active thermal insulation which is the most recent invention by BT & Sons, Hungary in 2011.
The thermal specifications for all the components of the building that have been recommended meet the Passivhaus standards. The entire structure after having built to the recommended specifications will be a zero carbon building.
Something that remains unexplored is the cost factor. The cost of sustainable buildings is higher as compared to the standard construction which has always been an obstacle in the way of sustainable development (Halliday, 2008).
How important is the cost factor?
‘It is unwise to pay too much, but it is worse to pay too little. When you pay too much, you lose a little money – that is all. When you pay too little, you sometimes lose everything, because the thing you bought is incapable of doing the thing it was bought to do. The common law of business balance prohibits paying a little and getting a lot.’
(John Ruskin, 1860 cited in Sandy Halliday 2008)
Annual Energy Balance Calculations | Eco House Design | Part 9
Posted by BenzuJK in Architecture, Design Guide, House Design, Sustainable Design on June 4, 2017
Annual Energy Balance | Renewable Energy Sources
In this article, we will calculate the total energy produced with the help of solar panels, energy used and total energy returned back to the grid.
Since the waste house has been designed using Passivhaus technique, it requires 4.47 kWh per day. As per the calculations in the section “Solar Electricity Generation” in the report, following results were obtained.
For 1kW capacity of solar PV array and considering 4.8 sunshine hours per day on average, total electricity produced would be 4.8 kWh of electricity per day whereas the requirement is 1630/365 = 4.47 kWh per day.
This indicates that adequate energy is being produced to cope with the calculated requirement.
The roof however offers a larger space and 4kW capacity solar PV can be installed as a result of which 4 x 4.8 = 19.2 kWh per day of electricity would be produced.
Total annual energy produced with the help of solar panels = 7008 kWh per annum
Mechanical Ventilation and Rainwater Harvesting | Eco House Design – Part 8
Posted by BenzuJK in Architecture, Design Guide, House Design, Sustainable Design on June 4, 2017
Mechanical Ventilation with Heat Recovery (MVHR)
The Waste House building is highly energy efficient, and to achieve that it has very high levels of air-tightness to prevent heat transfer between the house and surrounding environment. Hence, to provide adequate ventilation to the house along with maintaining energy efficiency, a mechanical ventilation system with heat recovery could be used. A heat recovery system with 92% heat recovery efficiency will be used which would be Passivhaus Institute certified.
Mechanical Ventilation. Source: www.homeventilation.co.uk
This system works by extracting heat from areas of a dwelling which generate heat and moisture, like the kitchen and bathroom, and then distributing that heat to other areas of the house. Living room and Bedrooms have air ducting installed to supply pre-heated fresh air into them.
Fresh air is drawn into the house with the help of a suction pump through the supply air ducting which is generally installed on the roof. Stale air is expelled from the house through another ducting, away from supply air ducting. The stale air is passed through the heat recovery unit before it is exhausted. Fresh air is also passed through the heat recovery unit, where it is heated and filtered before pumping it into the house.
Some systems have a feature so that when it’s warm outside, the air can bypass the heat exchanger to help keep the house cool. This system can potentially reduce heating costs and also keep the home environment fresh. It is a low-energy and highly efficient ventilation process.
The Waste House is built to Passivhaus standards, and hence a heat recovery ventilation system is necessary to satisfy efficiency requirements. This system can also be combined with ground source heat pump to improve efficiency of the process.
Solar Electricity Generation Calculations | Eco House Design | Part 7
Posted by BenzuJK in Architecture, Design Guide, House Design, Sustainable Design on June 4, 2017
Solar Electricity Generation | Renewable Energy Sources
Solar Panels (Photovoltaic Cells) can be used to convert solar energy into DC current, which is then fed into an inverter to convert it into usable AC current to power a dwelling. A generation meter unit shows how much power is being generated by the solar panels. Power generated by PV cells varies with the time of day and weather. In this waste house project, the architect has provided an excellent location on the south side to install solar panels.
Calculations:
Energy generated with the help of solar panels
In the southeast UK, the average sunshine hours per day is 4.8 hours. For a passive house design, the average energy required is 15 kWh per square meter per year. In this project, the waste house has a total area of 108.64 square meters, which puts the total electricity required in a year of about 1630 kWh. If we calculate electricity required per day, we come to 1630/365 = 4.47 kWh per day.