EXHIBIT 15 AWARENESS LETTER OF INDEPENDENT ACCOUNTANTS MidAmerican Energy Holdings Company Des Moines, Iowa We have made a review, in accordance with standards established by the American Institute of Certified Public Accountants, of the unaudited interim financial information of MidAmerican Energy Holdings Company for the three and six month periods ended June 30, 1999 and 1998 as indicated in our report dated July 26, 1999; because we did not perform an audit, we expressed no opinion on that information. We are aware that our report referred to above, which is included in your Quarterly Report on Form 10-Q for the quarter ended June 30, 1999, is incorporated by reference in Registration Statements No. 33-26256, No. 33-38431, No. 33-41152, No. 33-44934, No. 33-52147, No. 33-64897, No. 333-30395 and No. 333-74691 on Form S-8 and Registration Statements No. 333-30537, No. 333-45615 and No. 333-62697 on Form S-3. We also are aware that the aforementioned report, pursuant to Rule 436(c) under the Securities Act of 1933, is not considered a part of a Registration Statement prepared or certified by an accountant or a report prepared or certified by an accountant within the meaning of Sections 7 and 11 of that Act. DELOITTE & TOUCHE LLP Des Moines, Iowa August 11, 1999