Smart Metering is an important component of Smart Grids. Detailed load profiles are available through smart metering at a high resolution. Load profiles allow inferring detailed information on the end user by non-intrusive load monitoring. Therefore, these load profiles need to be regarded as sensitive data, and treated with security and privacy in mind. We propose a method that allows conditional access to different resolution levels of the load data, allowing access on a "need-to-know" basis only. For this purpose, a multiresolution representation of the load data is created using the simple Haar wavelet transform. Securing the portions of the wavelet representation pertaining to each resolution with a unique key allows to implement conditional access for smart meter data.