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Building efficiency
buildinr efficiencgy
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The built environment has a long lifecycle, during which it traditionally contributes to continuous CO2 emissions and inefficient use of energy. Building efficiency aims at reducing the negative impacts of these two phenomena, as well as adding the production of renewable energy to the mix. In order to accomplish these ambitious goals, a thorough integration of engineering, materials science and novel building concepts is needed.
Over the last few years the market for low-energy houses in Norway has experienced a rapid development. The demand for passive houses, i.e. houses with an energy loss of less than 25% of normal standard, is also growing rapidly, both in Norway and in Europe. This has led to an incipient development of new Norwegian products for this market. During the last 2-3 years zero-emission buildings have been planned, and the first ones will be completed in 2014. These buildings do not contribute to greenhouse gas emissions over their lifetime.
Technology status
Approximately 40 percent (87TWh) of the energy used in mainland Norway goes to lighting, heating and electrical equipment in homes and commercial buildings. 80 percent of this is electricity. In the building regulations scheduled for 2015, Passive House standard is expected to be the requirement for all new buildings. Further, two White Papers from the government to Stortinget: ‘Gode bygg for eit betre samfunn – Ein framtidsretta bygningspolitikk’ [Good buildings for a better society – building policy for the future] and ‘Norsk klimapolitikk’ [Norwegian Climate Policy] points toward stricter requirements. Both White Papers stresses that within 2020 the energy use in buildings should be nearly zero. This is also in accordance to the Energy Performance of Buildings Directive 2010/31/EU (EPBD). On 19 May 2010, the EU adopted the EPBD which is the main legislative instrument to reduce the energy consumption of buildings. Under this Directive, Member States must establish and apply minimum energy performance requirements for new and existing buildings. Moreover, the Directive requires Member States to ensure that by 2021 all new buildings are ‘nearly zero-energy buildings’. There will also be stricter guidelines on renovation of buildings. 80% of the buildings that exist today will also be available in 2050, but with reduced emission levels.
The greatest potential for increasing energy efficiency resides in the upgrading of existing buildings. The development of products, solutions and operational and management systems are central to achieving greater energy efficiency in the repair, remodeling and refurbishment.
Challenges
The solution to the high energy use and related emissions on the building sector is to develop buildings that do not contribute with greenhouse gas emissions during their life cycle, zero emission buildings (ZEBs). This can be done by harvesting more renewables energy than is used for construction and operation of buildings and for production of the materials used. The new requirements will result in the need for new and improved materials and technologies that will make it possible to reduce energy consumption and environmental impact of buildings
in a sustainable manner. The focus will be on reducing energy requirements in the operational phase using improved technologies for thermal insulation, glass and window technology, energy efficient ventilation systems, energy efficient systems for heating and cooling, energy efficient electrical equipment, control systems etc. Improved technologies for renewable energy are also important, such as building integrated solar (PV), solar thermal, biomass heating and heat pumps. The material’s and technologies’ environmental footprint must also be reduced where possible, because CO2 emissions from materials used in a building can be greater than the CO2 emissions from the operational phase of a zero emission building. In addition, it is equally important to ensure that individual technologies interact well together, for example, that systems for heating, ventilation and air conditioning work well with the building envelope materials and solutions, and that the indoor air quality and resource efficiency are maintained throughout the life cycle of the building. Outlook
The objective related to building energy efficiency will have to include the development of materials, products and solutions for existing and new buildings, commercial as well as residential. With enough critical mass, a market breakthrough can be effectuated, leading to acceleration in implementing the construction and operation of zero emission buildings. With the rise of ICT, new engineering concepts and models can be developed to design and operate the buildings. Examples here are controls for light, ventilation, heating/cooling, and monitoring of the indoor climate. With the availability of newer, more environmentally friendly and more cost effective materials, it is necessary to update our understanding of the behaviour these materials and the consequences this has for the performance of the built environment.
The solutions must be implemented both at an industrial scale (primarily for large buildings, major renovation projects and serial production of smaller buildings) and at a smaller scale (individual projects and renovation projects).
