**Exhibit 12.1**

 

**302CERTIFICATION**

 

I, Rafael Mateo A., certify that:

 

1.              Ihave reviewed this annual report on Form 20-F of Empresa Nacional deElectricidad S.A. (“Endesa Chile”);

 

2.              Basedon my knowledge, this report does not contain any untrue statement of amaterial fact or omit to state a material fact necessary to make the statementsmade, in light of the circumstances under which such statements were made, notmisleading with respect to the period covered by this report;

 

3.              Basedon my knowledge, the financial statements, and other financial informationincluded in this report, fairly present in all material respects the financialcondition, results of operations and cash flows of the company as of, and for,the periods presented in this report;

 

4.              Thecompany’s other certifying officer and I are responsible for establishing andmaintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e) and internal control over financial reporting (as defined inExchange Act Rules 13a-15(f) and 15d-15(f)) for the company and have:

 

(a)         designed such disclosurecontrols and procedures, or caused such disclosure controls and procedures tobe designed under our supervision, to ensure that material information relatingto the company, including its consolidated subsidiaries, is made known to us byothers within those entities, particularly during the period in which thisreport is being prepared;

 

(b)         designed such internalcontrol over financial reporting, or caused such internal control overfinancial reporting to be designed under our supervision, to provide reasonableassurance regarding the reliability of financial reporting and the preparationof financial statements for external purposes in accordance with generally acceptedaccounting principles;

 

(c)          evaluated theeffectiveness of the company’s disclosure controls and procedures and presentedin this report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by this reportbased on such evaluation; and

 

(d)         disclosed in this reportany change in the company’s internal control over financial reporting thatoccurred during the period covered by the annual report that has materiallyaffected, or is reasonably likely to materially affect, the company’s internalcontrol over financial reporting; and

 

5.              Thecompany’s other certifying officer and I have disclosed, based on our mostrecent evaluation of internal control over financial reporting, to the company’sauditors and the audit committee of the company’s board of directors (orpersons performing the equivalent functions):

 

(a)         all significantdeficiencies and material weaknesses in the design or operation of internalcontrol over financial reporting which are reasonably likely to adverselyaffect the company’s ability to record, process, summarize and report financialinformation; and

 

(b)         any fraud, whether or notmaterial, that involves management or other employees who have a significantrole in the company’s internal control over financial reporting.

 
| Date: March 16,  2006 |
|----------------------------|
|                       |
|                       | /s/ Rafael Mateo A. |   |
|                       | Rafael Mateo A. |
|                       | Chief Executive Officer |

 

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