Assessment of Hotel Hot Water Systems and Viability of Solar Water Heating: Case Study of Sarova Hotel Nairobi

Abstract

Hotel systems especially water heating consume significant amount of energy leading to high operational costs. High cost of electricity and fuel price volatility coupled with tighter environmental regulations on emissions have motivated hotels to invest in sustainable energy such as solar water heating (SWH). Studies have shown that the design and sizing of a SWH system is unique to every hotel depending on the hot water consumption patterns, climatic conditions and site location. This research focused on statistical analysis of recorded water-heating data in a case study hotel located in Kenya’s capital city to determine average daily hot water requirements, fuel consumption and system efficiency. The analyzed data together with solar resource data obtained from online renewable energy software – RETscreen was used to size and optimize a SWH system to meet up to 60% of the hotel’s hot water demand load. The results indicated that the hotel’s average hot water requirement was 48.06m3 and the corresponding energy demand load was 1955kWh/day. The designed solar hot water system was sized at 284.6m2 collector area and the system performance was evaluated to be 314.4MWh per year. The system cost was estimated at around 83,508.28 USD and the annual financial savings were around 29,756.55 USD. The results of this study were validated through a site visit to a hotel with an already installed SWH system which concurred that the sized SWH system for the case study hotel was reasonable. In conclusion, the use of solar water heating to meet hotel hot water demand load was found to be a viable undertaking based on the evaluated financial indicators.