The performance investigation of a grid connected solar photovoltaic system in a passive energy designed dwelling at the foothills of the Western Himalayas

Abstract

The unpredictability of the fossil fuel energy market and the noticeable growing understanding of its impact on the environment, research in reducing energy consumption in buildings, has gained significant traction. The UNEP (United Nation Environment Program) in its 2020 Buildings Global Status Report, suggests the level of CO2 emissions from the building sector is 38% of the total CO2 energy related emission worldwide. This is important in the subtropical regions where the CO2 emission percentage is likely to be higher due to the pattern and nature of energy consumption. The energy portion consumed in the residential sector on comfort cooling is the highest, and the main contributor of other than CO2 GHG (Greenhouse Gases), due to the use of refrigerants, while electricity needed to drive the power-hungry compressor motors is mostly generated from burning fossil fuels. In Southwest Asia, including the Gulf Region, which is the area chosen in this research, up to 70% of the electricity consumption during the long summer months, and approximately 50% annual average, is attributed to air conditioning. This energy consumption will continue to rise due to the unabating population growth, persistent demand for houses, and the growing impoverished neighbourhoods in many metropolises. Energy saving guidelines have become mandatory, particularly, for commercial, institutional, governmental and industrial sectors. However, this is to a lesser extent in the private residential sector. This is further compounded by the inability to enforce these guidelines. In addition, the heavily subsidized electricity tariff in comparison with other sectors. In some of the GCC (Gulf Cooperation Council) countries, the residential tariffs can be up to 13 times lower than other sectors and 20 to 25 times lower than the cost of electricity production. In Kuwait, which holds 7% of the global oil reserves, experiences electricity blackout during the long summer months due to the difficulty of keeping up with the growing demand for electricity. In this research a number of measures to reduce electricity consumption has been reviewed. • The house performance throughout the various stages of construction and occupancy has been examined using the wealth of data available, which extends over a period of 12 years - during construction (2012 to 2015), before the installation of a grid connected 12.18 KWp Solar PV (2016to 2020), and after the installation of the Solar PV system (2021 to 2023). TRNSYS used to simulate the Solar PV installed system, with a cross reference using PVGIS. 12 simulation cases at different tilt and azimuth angles and tracking on one, and two axes were conducted. This including the actual case of exported monthly electricity units. TRNSYS and PVGIS results exhibited acceptable margin of error in the annual total for each case when comparing with actual, from -2% to +7%. Accounting for the number of electricity blackout hours was quite challenging, otherwise the difference between actual and simulated would have been even less. The analysis proved that up to 50% more KWH can be generated by the same system when tracking on 2 axes, and approximately 40% when tracking on the Azimuth only. Tracking on two axes is commercially prohibitive, but on one axis only is feasible.