Optimizing economic benefit of rooftop photovoltaic (PV) systems through lowering energy demand of industrial halls

Industrial halls are characterized with their relatively high roof-to-floor ratio, which facilitates ready deployment of photovoltaic (PV) systems on the rooftop. To promote deployment of PV systems, feed-in tariff (FIT) higher than the electricity rate is available in many countries to subsidize the capital investment. FIT comes in different forms. If net FIT is the case, surplus electricity generation at the high FIT at each of the hours is desirable. However, increasing generation capacity also implies higher capital investment. Industrial halls are usually subject to high energy demand due to the many manufacturing processes, lighting, and the corresponding amount spent on space conditioning to remove the excess heat gain. Therefore, rather than increasing generation capacity, surplus electricity generation can also be achieved by lowering the energy demand of the building. Building energy performance simulation tools can be used to explore the different building design options that could lower the demand. In this paper, single-objective optimization on investment return will be deployed to study the cost effectiveness among different options in lowering energy demand. The idea will be demonstrated with a case study of a warehouse.