Previous research has revealed industry differences in respect of environmental reporting in South Africa. However, these studies concentrated on particular types of environmental reporting and therefore precluded many other types of environmental reporting in the annual reports surveyed. Past surveys also awarded equal credit to any reference to a particular type of environmental information, whether it comprised a single sentence or several pages.
The annual reports of the top 100 companies, in terms of market capitalisation, were analysed and a sentence count of environmental disclosure was done with the use of the Hackston & Milne (1996) methodology. The group of energy companies was defined as comprising companies in energy-intensive industries or companies that are producers of energy carriers. The survey revealed that these companies disclosed significantly more environmental information than other companies, in total and in each category
These findings are consistent with the notion of legitimacy, which holds that companies cannot prosper if their aims and methods are not perceived to be in line with that of society. For this reason, companies that have the most obvious environmental impact tend to disclose more environmental information than other companies in an effort to legitimise their aims and methods in the eyes of society.