Group 32



            ENERGY EFFICIENT SOLUTIONS IN MODERN BUILDING

Saving energy is one of the most important topic for today. In the present days, all over the world is paying huge attention to the problem of resource conservation about heating buildings and its efficient use. Modern buildings has huge reserves to increase their thermal efficiency.

In the past, energy efficient buildings did not take a considerable significant. But today modern buildings pay unique attention for energy efficient solutions.

Efficient energy use, which is called energy efficiency, is the goal to decrease the amount of energy required to supply products and services. As example, insulting a home allows a building to unusable heating and cooling energy to achieve and maintain comfortable temperature. Install of LED lights, fluorescent lights or natural skylights decreases the amount of required energy to reach the same level of lighting compared with the using traditional incandescent light bulbs. Not only have that but great efficiency windows and insulation in walls, ceilings, and floors increased the efficiency of building envelope also. Alternative strategy, passive solar building design, is often applied in low-energy homes.

There are number of motivations to increase energy efficiency. Reducing energy use reduces energy costs and may result in an economic cost saving to users if the energy savings offset any additional costs of implementing an energy efficient technology.

     Usually, there are following strategies for the design of energy efficient buildings,

• ·       Minimization of losses
• ·       Maximization of solar gains –Heating case
• ·       Minimization of solar gains-Cooling case
• ·       Minimization of electricity demand for artificial lighting

 1.   Minimization of losses-Compactness

Heat losses are taken an important role for the energy performance of buildings. Reliant to the building type (housing, office, schools, commercials etc.) transmission losses can have the highest percentage of all losses. Therefore the main design related measure should be the decrease of heating losses by minimization of the shape/volume ratio. Specially for an cost-effective realization of passive houses or zero and plus energy houses compactness is of maximum importance, as worse compactness means higher construction costs.

            2. Maximization of solar gains- Heating case

During the heating period a maximization of passive solar gains should be the main target to reduce the heating energy demand. Optimized interaction of location, sizes of windows and one-use thermal mass are the key elements. Superior design of windows and a special sunblind with reflector (reflecting sunlight to the ceilings) supports a maximization of solar energy gains for the rooms. Massive floors, walls and special designed ceilings (beamed concrete slabs with large surface area) are used for the storage solar energy.

            3. Minimization of solar gains- Cooling case

⏩Transparent building elements (windows)

Orientation and dimension of transparent building elements (windows) have important effect on the cooling demand. Intellectual shading elements with different orientation are additional measures for the reduction of solar gains.

⏩Natural cooling with passive night ventilation

The office buildings up to 2/3 of the total cooling load can be managed by passive cooling, not using with mechanical energy. Night temperature in summer around 15celcios suitable thermal building mass and the possibility of natural stack ventilation are requirements for this cooling kinds.

⏩Natural ventilation by wind

Innovational mechanical ventilation systems are used for high rise buildings natural ventilation concepts of wind. The new office of the European Central Bank in Frankfurt is the first office building using only natural ventilation. The building design is based on wind and ascending forces around and in the building.

       4.  Minimization of electricity demand for artificial lighting

In addition to heating and cooling the energy demand for artificial lighting is of significance for the energetic performance of buildings. Huge overall width buildings like office buildings, tend to have substantial energy demand for artificial lighting. Innovative daylight concepts development is the most important strategy to decrease the energy demand for lighting. Daylight concepts always pay attention for the combination with aspects for heating and cooling.

             5. Active solar energy

Active use of solar energy (thermal and photovoltaic solar collectors) on one hand has strong input on the design of the building and on the other hand the use of solar energy also has strong effect on the environmental performance of the building, compared to other HVAC systems. Requires. A comprehensive integration of solar panels in the architectural design concept and influences the design of building strongly are required by the intensive use of solar energy. Solar panels can be attached on walls and roofs, although in urban context roofs with better conditions.