Stagnation and Solar Fraction Analysis on Solar Thermal Integration in Southeast Asia

The depletion and negative impacts of using fossil fuels have caused rapid technological growth in renewable energy sources. Southeast Asia is rich in solar resources, which makes generating thermal energy from a solar thermal system highly attractive. The objective of this article is to propose a new method for estimating solar fraction and possible occurrences of fluid stagnation based on a daily heat storage profile, reduce the possible stagnation by adjusting the storage volume, and comparing the economic performance of the proposed system among different countries in Southeast Asia. Given a solar heat system specification and irradiance data, the method involves four steps: the establishment of a daily heat storage profile, system performance analysis, reduction of the stagnation by adjusting the ratio of the storage volume to solar collector area, r(sto/coll) and the target heat storage percentage for night cooling, F-nc and techno-economic analysis. As a result, the proposed solar thermal system integration located in Naypyidaw, Myanmar, gives the lowest LCoH (levelised cost of heat) of 0.194 $/kWh, followed by Kuala Lumpur in Malaysia and Banyuwangi in Indonesia. As a comparison, the LCoH of a gas-fuelled heating system with a higher amount of heat demand encountered is 0.15 $/kWh (Wahed et al. UPM Alam Cipta, Vol. 8, No. 3, pp. 32-43,2015).