Energy saving is one of the main global problems and trends of the 21st century. Today, humanity has two options for energy saving: to minimize the consumption of non-renewable energy carriers or to use energy resources as efficiently as possible. So, for example, to optimize energy consumption in buildings, energy-saving materials and structures are widely used today. Ksenia Pashkevich, Lead Architect at Metropolis, told the Energy to People magazine (No. 8/93, 2019) about the ways in which it is possible to reduce the energy consumption of buildings today.
“Currently, the issue of energy saving is the most relevant in the construction industry. This is due to both environmental and economic aspects. Environmental degradation due to excessive emissions of various gases, limited reserves of natural resources, oil crises and increased tariffs for heat and electricity are just a few of the reasons for the development of energy efficient technologies,” explains Ksenia.
“The construction sector is one of the main consumers of energy. Heating, ventilation and air conditioning of buildings consumes two thirds of the total energy consumed by buildings. In total, buildings use about 40% of the world's energy consumption.
Heat losses in buildings vary depending on the number of storeys, the type of building envelope, the quality of construction work, and so on. For example, the heat loss of a typical nine-storey building is as follows: 45% of the heat leaves through the building envelope (it means it serves as a fence or separation of rooms inside the building); through windows - 35%; through roofing, attic and basement floors - an average of 10-15%. Therefore, systems of energy-efficient technologies aimed at the rational use and replenishment of consumed energy are actively used in construction. After the global oil crisis of 1974, the world community first thought about the construction of energy efficient buildings, which are a combination of architectural and engineering solutions that minimize energy consumption while providing a microclimate in the premises. “In Russia, energy saving technologies began to be thought about since 1996 after the adoption of federal law No. 28-F3 “On Energy Saving”. Later, a new SNiP 23-02-2003 “Thermal protection of buildings” was introduced. The energy efficiency classes of buildings were also formulated, and the requirements for heat transfer of enclosing structures were tightened,” notes Ksenia Pashkevich.
“Many projects in Western Europe, Scandinavia, America prove that the use of energy efficient technologies is not utopia. The fundamental factor is the decision to build an energy-efficient building at the early stages of design, using an integrated approach,” notes Ksenia Pashkevich. Today, builders have at their disposal a significant number of design and engineering solutions that reduce the overall level of energy consumption of the building. Many of them are aimed primarily at improving the thermal efficiency of building structures. “Unfortunately, in Russia, an integrated approach to the design of energy efficient buildings is often not used. I believe this is due to the fact that the construction of energy efficient facilities requires significant investment in the initial stages of construction. The most common technique in our country is the use of various energy-efficient materials for building envelopes. The market has a huge variety of new, modern and heat-efficient building materials and technologies. Energy-efficient materials and technologies are applicable to various types of construction and various climatic zones. Which material is better to use depends on the specific case and the tasks set,” notes Ksenia Pashkevich.
These energy-efficient materials can be divided into two typical groups: thermally homogeneous enclosing structure and thermally inhomogeneous enclosing structure. Homogeneous structures, in turn, are divided into solid and hollow materials. This category includes materials from lightweight concrete, such as polystyrene concrete, foam concrete, wood concrete, gas silicate, expanded clay concrete and so on. Non-homogeneous materials include multi-layer, self-supporting and hinged energy-efficient materials, such as building blocks made of silicon granite, sandwich panels. The most widely used system of insulation of enclosing structures today is the system of ventilated and non-ventilated facades. Together with the thermal insulation of walls, as a rule, insulation is also carried out at the junction of the roof, taking into account the subsequent shrinkage of the building and changes in the properties of a number of materials under the influence of temperature. The same materials as for walls are often used for thermal insulation of roofs, floors and foundations. As already noted, the windows of buildings also become the cause of significant heat losses. Although most modern double-glazed windows insulate a room better than old wooden windows, it can be difficult to achieve a drastic reduction in heat loss with them. To this end, various types of energy-efficient glass are produced today. There are I-glass, IM-glass, K-glass types. Such selective glasses, which work on the principle of the Earth's atmosphere, are capable of retaining up to 90% of heat. The fact is that they let short-wave heat rays into the room and reflect long-wave ones towards their emitter (in winter - towards the room with heating devices, and in summer - towards the street heated by the sun), respectively, reducing heating and air conditioning costs. In addition, they reduce the likelihood of condensation on the glass and prevent fading of wallpaper, furniture upholstery and interior items.
Read the full material in Energy to People magazine.