Cleaning innovative daylighting systems: Economic assessment

The economic feasibility of innovative daylighting systems (IDS) is usually estimated without considering the impact of cleaning costs. This study determines the most sensitive parameters affecting the cost of cleaning, whether the process is manual or automated. The net present value method was used to estimate the payback period of investments in automated cleaning systems. This study recommends that the development and implementation of automated cleaning systems not exceed the cost of $10/m(2) of the served area. Auto-cleaned IDS are expected to require 32% more time than normal IDS to return the investment. This work generated two matrices for predicting the economic performances of cleaning systems prior to their implementation. The first parametrically presents the payback periods of automated cleaning systems in a wide range of configurations. The second parametrically presents the annual manual cleaning cost as a percentage of the monetary value of the energy savings gained due to utilization of the IDS. For the IDS to achieve peak economic performance, the annual manual cleaning cost must be less than the annual energy savings, which can be expected for a wide range of operating circumstances using the generated matrix. (C) 2017 Elsevier B.V. All rights reserved.