International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 03 Issue: 05 | May-2016 www.irjet.net p-ISSN: 2395-0072 © 2016, IRJET | Impact Factor value: 4.45 | ISO 9001:2008 Certified Journal | Page 38 Design features of Energy storage systems for Green buildings: An economic comparison with off-grid and on grid solutions Tapas Ch. Singh 1 , G.R.K.D. Satya Prasad 2 ,Chetana Samantaray 3 , Chinmaya Sahu 4 , Anamika Kumari 5 , Saswat Mohapatra 6 , 1 Assistant Professor , Department of Electrical Engineering, GIET, Gunupur, Orissa, INDIA 2 Associate Professor, Department of Electrical Engineering, GIET, Gunupur, Orissa, INDIA 3,4,5,6 Final Year UG student, Dept. of Electrical Engineering, GIET, Gunupur, Orissa, INDIA ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract: The present power crisis and global scenario trend is favoring renewable energy sources. Where renewable energy sources are available – solar, small hydro, biomass, wind – they can often provide remote communities and businesses with the most reliable and affordable source of electrical energy. But, most of the Renewable energy technologies depend on Battery backup. Batteries can supply power as needed at levels much higher than that generated and during times of low demand the excess can be stored. If enough energy is available from the renewable energies such as PV systems, wind energy, micro hydro powers etc., are key part in Green buildings. In this paper, an analysis has been done with various strategies for energy storage technologies for Solar PV assisted Green buildings. The work further will be extended for practical implementation in Green building which is going to be constructed in GIET campus. Key Words: Battery storage, Simulation, Homer, Green buildings, autonomy 1. INTRODUCTION Today’s world is at a critical point due to resource unavailability, increased pollution, changing climate the upcoming generation is going to face problems. To address these unsecured energy security there is a need to shift towards renewable energy sources. But, the main disadvantages of renewable energy sources are they are non-conventional. There is a technical barrier to generate the energy continuously, hence That is why we are in a hurry to find the alternatives that will ensure our acquired wealth and further growth on a long term basis. As demand of electricity throughout the world is high, so here comes the use of energy storage which will partly eliminate these problems. With the rapid development in the field of renewable energy resources, scientists and engineers have already integrated different energy storage technologies with these budding resources. Implementation of different energy storage technologies along with green building is one of the real time examples of this. This energy stored can also be retrieved at the time of high demand which means less chance of grid became overloaded and interrupting the power supply. 1.1 Energy storage systems and Green buildings A green building is defined as one which optimises energy efficiency as compared to normal conventional building. It also helps us in saving money up to 50% in the form of energy cost. There are several approaches found that can be implemented along with the green building to store energy efficiently. These technologies are broadly divided into six main categories such as fly wheel, batteries, Thermal energy storage (TES), Compressed air energy storage (CAES), Pumped hydro energy storage (PHS), fuel cells. These energy storage technologies has different uses at different stages like PHS, CAES, large-scale batteries, flow batteries, fuel cells, solar fuel and TES can be used for efficient energy management, whereas capacitors/super capacitors, flywheels and batteries are in the group of power quality and reliability. Advancement in technologies has made these more reliable and also helped in reducing its cost by making these more economical. Moreover flywheel, compressed air energy storage,, hydrogen storage, thermal energy storage are large scale methods of energy storage whereas small scale specific storage comprises of flywheel, capacitor, super capacitor, battery bank. If we install banks of energy storage battery into electricity grid the electricity provider can easily add in wind and solar energy. The batteries store the renewable energy and when needed the energy can be easily released to the grid which ultimately makes the system more reliable and smoother. Green building can lessen energy consumption in various ways. Firstly we can reduce the embodied energy of the building through efficient design. Specific strategy should be adopted for placing windows and skylights so that we can minimize the use of electrical lighting during daytime. High Quality insulation diminishes the temperature regulation cost during summer and winter. Moreover house can increase passive heating and cooling. Energy efficiency is the most sensitive issue and essential component of green building. It also plays a key role in its success. A green building is always equipped with a solution that increases the electrical energy management, reduce consumption and help in sustaining quality energy. In these buildings capacitor bank increases the efficiency of the installation and