CSRD readiness for a mid-size energy group: first ESRS sustainability report

The Challenge

The Corporate Sustainability Reporting Directive (CSRD) requires mid-size European companies to publish sustainability information in accordance with European Sustainability Reporting Standards (ESRS) starting from fiscal year 2025. For an energy group with 150 million euros in revenue and 500 employees operating across three Spanish regions, compliance represented an unprecedented challenge: the company had never published a structured sustainability report, its environmental data was siloed across departments, and none of its senior managers had received specific training on ESG taxonomy.

The risk extended beyond regulatory exposure. Several corporate clients had begun including sustainability reporting requirements in their supply contracts, and two financing institutions had conditioned the renewal of credit facilities on the presentation of verifiable ESG data. Getting CSRD-ready was both a compliance obligation and a business imperative.

Our Approach

The project began with a double materiality assessment, the cornerstone of CSRD compliance. BMC facilitated a structured consultation process with 28 stakeholder groups — employees, clients, suppliers, local communities, and financiers — to identify which sustainability topics are material both in terms of their impact on the business (financial materiality) and the business’s impact on society and the environment (impact materiality). The result was a double materiality matrix with 12 prioritized material topics, including energy transition, water management, supply chain practices, and employee wellbeing.

From that foundation, we designed the ESG data collection framework: 48 quantitative indicators aligned with the applicable ESRS standards (E1, E3, S1, and G1 as priorities), with defined data sources, capture frequency, departmental owners, and internal verification procedures for each indicator. We implemented the framework within a business management tool already in use at the company to minimize adoption friction and avoid introducing additional software complexity.

In parallel, we developed and delivered a 12-hour training program for the 15 area managers most involved in the reporting process, covering ESRS fundamentals, reporting responsibilities, and data quality criteria. We also prepared disclosure templates aligned with the narrative reporting requirements of each applicable ESRS.

Results

Six months before the first mandatory filing deadline, the company had a documented and externally reviewed double materiality assessment, a functioning ESG data collection system with two years of historical data, and a first draft sustainability report structured in accordance with ESRS and ready for external auditor review.

The early completion allowed the team to identify and close data gaps with sufficient lead time, avoiding the risk of presenting incomplete information in the first reporting year — a common issue for companies that begin CSRD preparation too late. Two of the financing institutions have since confirmed their intention to open new green credit lines contingent on the quality of the final report.