Internal audits of an EnMS can be performed by workers of the company, or by outsourced professionals appointed by the company and their work on its behalf. Auditor independence can be demonstrated by an auditor being free from responsibility for the activity being audited. An energy audit or energy assessment is not the same concept as an internal audit of an EnMS. The clause - 9.2 is related to Internal audit, it has two sub-clauses.
As per clause - 9.2.1, the organization needs to perform internal audits of the EnMS at designated and designed intervals to offer the following important information on the EnMS:• The EnMS Enhances energy performance• The EnMS Conforms to:    • the company's own requirements for its EnMS;    • the energy policy (check clause - 5.2), objectives and energy targets (check clause - 6.2) developed by the company.    • the requirements of ISO 50001:2018 standard• The EnMS is robustly applied and maintained.