evidence from national and international programmes shows that while efficient components might yield minor gains systems optimization can yield much larger gains percent with payback periods of less than two years eclac garcia et al energy management systems can help firms develop an energy use baseline actively manage energy costs and document savings for internal and external use such as greenhouse gas emission credits a good energy management system is vital for identifying opportunities for sustainable energy savings worrell a successful energy management system starts with a strong organizational commitment a study of turkey s textile sector suggests that implementing an energy management system companywide is the best approach ozturk energy management systems involve costs in wages consultancy and other fees so their cost effectiveness varies with the firm s size and energy intensity