Aggregate long-run own-price elasticity -1.64 is the headline result the authors foreground ('electricity is a luxury rather than a necessity') || 'The price elasticity of demand for electricity is significant with a negative sign and is equal to -1.64. This implies that at aggregate level, electricity is a luxury rather than a necessity' (p.86)
Khan, M. A., & Qayyum, A. (2009): "The demand for electricity in Pakistan." OPEC Energy Review, 33(1), 70–96.