GENERAL

          Sustainable Properties are homes which are designed with the principle of "sustainability" and "energy conservation" to become more energy and cost efficient as they provide a return on those capital gains of construction. Properties that would be both modern and environmentally friendly.

          Bioclimatic design, ecological and environmentally friendly building materials, new green technologies and renewable energy use are the hallmarks of such residence.

Energy efficiency in buildings

            The type and amount of energy used by households varies from country to country depending on the level of income, physical assets and available infrastructure to supply and generation. In the U.S., for example, the residential sector consumes around 21% (38% with the commercial sector) of the total energy consumption in the country, according to 2004 figures, while this percentage was 42% for the EU in 1999 .

           The lion's share of energy consumption in houses owned by the heating and cooling of space. Illustration, in the U.S. according to data from the Department of Energy, air conditioning consumes 44% of total energy, water heating 13% lighting 12%, cooling to 8%, etc. These figures are of course averages and apparently are not the same everywhere since it is inextricably linked to local climatic conditions and the availability of techniques and technologies (US Dept. of Energy, "Buildings Energy Data Book" (August 2005), sec. 1.2.3).

           To prove this, an example is Great Britain, where the rate of heating of the interior is 60% for water heating 25% Etc. (UK Department of Trade & Industry).

           Besides the energy consumption is quite large as the share of homes on the emissions of carbon dioxide in the air. To this figure is 21% of total carbon dioxide emissions from activities related to energy in the U.S. in the year 2005 (Emissions of Greenhouse Gases in the United States 2005, EIA).

           In Great Britain, houses are responsible for 30% of global emissions of carbon dioxide in the atmosphere according to figures from the Environment Committee of the British Parliament for the year 2004 (United Kingdom Parliament - Environmental Audit Committee - Housing Construction-http://www.publications.parliament.uk/pa/cm200405/cmselect/cmenvaud/135/13 507.htm # a23).

           In 2002, emissions of carbon dioxide from the residential sector and services represent 14% of total global emissions, while the rate for countries belonging to Organization for Economic Cooperation and Development (OECD) is at 37% as is clear from the review of world energy 2004 (World Energy Outlook 2004).

          Energy efficiency is therefore perhaps the most important aspect, but both environmentally and economically, which should be considered in the construction and use of a dwelling. Apart from the fact that energy production and use contribute to air pollution and global climate change data, additional energy costs are a major household expenditure, particularly those on low incomes. The rational use of energy is therefore not only improves the environment but can also contribute to greater economic prosperity of the owners or occupants. At the national level and beyond, energy efficiency and renewable energy are perhaps the best practices for energy self-sufficiency and independence from foreign energy sources in unstable parts of the world and to reduce air quality impacts (City of Los Angeles Environmental Affairs Department).

          In energy-efficient buildings, design for energy efficiency starts with a methodological reduce heating and cooling loads of the building, namely those imposed by climate and those produced by human activities and equipment, operating through physical capacity of the building and microclimate. With all the loads are minimized, the mechanical systems are selected on the basis of maximum efficiency can be achieved with less fuel consumption. The energy efficiency of buildings, defined as optimizing the performance of each part and system of the building, both individually and in combination with other systems that are energy intensive, such as air conditioning, lighting, hot water, etc. The integrated design is can be combined with the use of renewable energy, which, as noted above, help to reduce dependence on fossil fuels and reducing emissions of greenhouse gases (New York City Department of Design and Construction).

             The energy efficiency of a building should be taken into account at all stages of design. The orientation of the building is one of the essential factors in energy efficiency in order to be able to make maximum use of solar energy and for heating and lighting. Moreover, depending on the orientation of the building is the design of interior spaces of which should favor the use of unconventional techniques to meet the energy needs of the building. Good insulation of the building and the use of natural ventilation techniques can significantly reduce the load of mechanical air conditioning and heating, thus reducing requirements for conventional fuels.

Potential energy savings from specific measures

Bioclimatic Design

Passive and active solar systems, bioclimatic design, natural lighting and natural cooling can reduce energy consumption by 60%.

Green generation

Locally available renewable energy, cogeneration / heat, district heating and heat pumps have an additional energy savings potential.

Lighting

Lighting consumes 14% of the total energy in the building industry. Using more efficient components and control systems and integrating daylighting techniques can achieve savings of 30-50%.

Air conditioning

Expected doubling of energy use for air conditioning by 2020. A saving of around 25% can be achieved by air conditioning systems to ensure minimum efficiency requirements.

Boilers

n the EU 10 million domestic boilers are more than 20 years. Replacing them can save 5% energy for heating.

Elias Plastiras

Mechanical Engineer - Mechanical

Energy Consultant