An ecological feasibility study for developing sustainable street lighting system Khurram Shahzad a, * , Lidija  Cu  cek b , Muhammad Sagir c , Nadeem Ali a , Muhammad Imtiaz Rashid a, d , Ruqia Nazir e , Abdul Sattar Nizami a , Hamad A. Al-Turaif f , Iqbal Mohammad Ibrahim Ismail a a Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, P.O Box: 80216, Jeddah 21589, Saudi Arabia b Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor, Slovenia c Department of Chemical Engineering, University of Gujrat, Pakistan d Department of Environmental Sciences, COMSATS Institute of InformationTechnology, 61100, Vehari, Pakistan e Department of Chemistry, Kohat University of Science and Technology, Kohat, Khyberpakhtunkhwa, Pakistan f Department of Chemical Engineering, King Abdulaziz University, Jeddah 21589, Saudi Arabia article info Article history: Received 28 December 2016 Received in revised form 13 November 2017 Accepted 8 December 2017 Available online 22 December 2017 Keywords: Ecological evaluation Street lighting Outdoor lighting Sustainable Process Index Carbon footprint abstract The recognition of the humans, vehicles or any other objects in the outdoor environment, such as roads, streets, pedestrian ways, car parking and public parks, is only possible with illumination after dark. The outdoor lighting consumes significant amounts of electricity. The best short-term payout period for reduction in energy consumption is implementation of energy efficiency solutions. A shift from tradi- tional illumination technology to the advanced lighting solutions has the ability for significant energy savings. The main focus of this study is to find out the most suitable, environmentally friendly and “green” solution(s) to fulfill the outdoor lighting requirements. It includes ecological impact assessment of commonly available lighting technologies for outdoor illumination, such as high pressure sodium, compact fluorescent and light emitting diode, by using Sustainable Process Index methodology. The effects of different alternative energy resources and the impacts of geographical locations due to vari- ations in energy provision system (i.e. energy mix) are also considered in this study. The obtained results show that Sustainable Process Index ranges from 258 km 2 to 7760 km 2 and carbon footprint from 930 t CO 2 eq. to 48,496 t CO 2 eq. to fulfill lighting requirement for 100,000 h of lighting. These results are compared with Sustainable Process Index and Carbon Footprint caused by high pressure sodium and light emitting diode luminaires providing electricity from Saudi Arabian electricity network. © 2017 Elsevier Ltd. All rights reserved. 1. Introduction The Kingdom of Saudi Arabia (KSA) having plentiful hydrocar- bon resources is one of the world's leading oil producer and exporter (Gelil, 2015). At the same time, KSA was also the 12th largest primary energy consumer in 2013. The energy statistics of KSA over the last years reveal that electricity demand has increased at the rate of 5.8% from 2006 to 2010 (Zafar, 2014). Currently, about 60% of energy is provided by the petroleum, while natural gas fulfills the remaining energy provision requirements. The KSA has 55 GW installed capacity of electricity generation, which is planned to be increased to 120 GW by 2032 (KACARE, 2012). The per capita energy consumption in KSA is more than twice the global average, although it is lower than in other Gulf States. This high energy demand is putting immense load on economy as well as on envi- ronment. It is necessary to adopt advanced energy conservation methodologies to minimize the impact of high energy consumption in KSA (OECD/IEA, 2015). In KSA almost 80% of the total energy production is consumed by the buildings sector. This energy is mainly consumed for air conditioning, illumination and operation of other electrical and electronic devices (SEEC, 2013). The main consumer of electricity having 50% electricity consumption is air conditioning (Waide et al., 2006). The energy consumption for illumination purposes covers about 23%e40% of the total energy consumption in the world (ICAEN, 2016). In accordance to the assumption that 19% of world's * Corresponding author. E-mail addresses: shahzadkhu@gmail.com, kramzan@kau.edu.sa (K. Shahzad). Contents lists available at ScienceDirect Journal of Cleaner Production journal homepage: www.elsevier.com/locate/jclepro https://doi.org/10.1016/j.jclepro.2017.12.057 0959-6526/© 2017 Elsevier Ltd. All rights reserved. Journal of Cleaner Production 175 (2018) 683e695