# Smart Meter Privacy with Renewable Energy and an Energy Storage Device

## TL;DR

This paper investigates how renewable energy sources and rechargeable batteries can enhance smart meter privacy by reducing information leakage, with theoretical analysis and numerical results demonstrating privacy gains and the importance of storage capacity.

## Contribution

It provides a novel information-theoretic framework for quantifying smart meter privacy considering renewable energy and storage, including explicit expressions for extreme cases and numerical analysis for finite capacity.

## Key findings

- Privacy improves with more renewable energy availability.
- Larger storage capacity enhances privacy gains.
- Infinite storage capacity achieves minimal information leakage.

## Abstract

A smart meter (SM) measures a consumer's electricity consumption and reports it automatically to a utility provider (UP) in almost real time. Despite many advantages of SMs, their use also leads to serious concerns about consumer privacy. In this paper, SM privacy is studied by considering the presence of a renewable energy source (RES) and a rechargeable battery (RB), which can be used to partially hide the consumer's energy consumption behavior. Privacy is measured by the information leakage rate, which denotes the average mutual information between the user's real energy consumption and the energy requested from the grid, which the SM reads and reports to the UP. The impact of the knowledge of the amount of energy generated by the RES at the UP is also considered. The minimum information leakage rate is characterized as a computable information theoretic single-letter expression in the two extreme cases, that is, when the battery capacity is infinite or zero. Numerical results are presented for the finite battery capacity case to illustrate the potential privacy gains from the existence of an RB. It is shown that, while the information leakage rate decreases with increasing availability of an RES, larger storage capacity is needed to fully exploit the available energy to improve the privacy.