Assurance Report

To the stakeholders of n.v. Nuon

Engagement and objective

We have been engaged by the Management Board of n.v. Nuon to perform the following procedures on the 2006 Sustainability Report, the Report, as set out below.

  1. To audit the data as included in the report and marked by reference with a triangle ():
    • the fuel mix of electricity supplied to consumers;
    • the "NatuurStroom" accounts;
    • the sustainable energy production;
    • de CO2 emissions of the electricity- and heat generation plants;
    • the quantity of electricity generated from fossil and sustainable energy sources;
    • the employee profile with respect to the number of FTEs and the number of employees engaged;
    • the level of subsidies and investments relating to sustainable energy production;
    • the key financial data.
  2. To review:
    • the other elements included in the Report.

Audit procedures focus on obtaining reasonable assurance, supported by sufficient evidence. Review procedures focus on obtaining limited assurance to support our conclusions. The detail and level of review procedures performed are significantly less than for an audit engagement. Consequently, the level of assurance provided is lower than would be obtained in an audit engagement. In our opinion, the present combined engagement meets a rational objective.

The Report has been prepared under the responsibility of the Management Board of n.v. Nuon.

Reporting criteria

The reporting criteria of n.v. Nuon are based on the Sustainability Reporting Guidelines of the Global Reporting Initiative (GRI) 2006, G3, published in October 2006, as described in the chapter titled "About the Report". We consider these reporting criteria ('the n.v. Nuon reporting principles') to be relevant and sufficient for our engagement.

Work performed

The work has been performed by a multidisciplinary team consisting of professional auditors and environmental and social experts. We conducted our procedures in accordance with Dutch law, including Assurance Standard 3410N "Assurance Engagements relating to Social Responsibility Reports", drawn up by the professional body of Dutch auditors ("NIVRA").

Audit procedures
With respect to the audit part of the Report, we focused on:

  • Testing of the relevant internal control measures for their effectiveness during the reporting period;
  • Analytical review, overall reconciling controls and detailed controls directly focussed to the data reported. The detailed controls have been carried out by means of detailed sample testing, using internal and external information sources, such as documents and third party confirmations;
  • Reconciliation of the key financial data set out in the Report to the consolidated annual accounts of n.v. Nuon for the year ended 31 December 2006, on which an unqualified auditors? report dated 9 March 2007 was issued.

Review procedures
Our main review activities consisted of:

  • Performing a background analysis and obtaining insight into the market sector, relevant social issues, relevant laws and regulations, and the characteristics of n.v. Nuon;
  • Assessing the reasonableness of the reporting policies, also in light of the information requirements of the intended stakeholder groups;
  • Review of the stakeholder review conducted;
  • Conducting interviews with responsible staff members, primarily focussed on:
    • Recognizing risks in the external environment and the organisation itself, and analysing to what extent these risks are sufficiently addressed by internal control measures in place;
    • Evaluating the plausibility of the qualitative and quantitative information presented through the Report;
  • Reviewing the quantitative data, mainly by performing analytical review;
  • Reviewing the data collection and recording procedures, including the aggregation process of data to the information as presented through the Report;
  • Reviewing the information provided by the various divisions of n.v. Nuon and analysing, by means on a test base checking the underlying systems and/or source documents;
  • Evaluating the overall presentation of the Report, also by reviewing the consistency of the information, based on the above-mentioned reporting criteria.

Conclusions

With respect to the audit activities
We conclude that the information with respect to the fuel mix of electricity supplied to consumers, the "NatuurStroom" accounts, the sustainable energy production, the production figures of the plants, the CO2 emissions of the electricity- and heat generation plants, the quantity of electricity generated from fossil and sustainable energy sources, the employee profile with respect to the number of FTEs and the number of employees engaged, the level of subsidies and investments relating to sustainable energy production, and the key financial data, is presented reliably and sufficiently. The audited data are marked for reference with a triangle ().

With respect to the review activities
With respect to the other elements presented through the Report based on our review procedures performed, nothing has come to our attention which causes us to believe that the Report does not, in all material aspects, reliably and sufficiently presents the n.v. Nuon policies relating to sustainability, and to the management, events and results in that area during the year under review, in accordance with the n.v. Nuon reporting principles.

Amsterdam, 11 april 2007
PricewaterhouseCoopers Accountants NV
drs. J. van Hoof RA