This report has two aims. First aim is to evaluate the e_ect of installing a home energy monitoring system on the electrical consumption of inhabitants of a Smart City. Numerous literature urges for the need of more informative energy billing; historic, extra information or comparative feedback. This thesis conducts a further evaluation in scope of further validating these _ndings. Second aim is to compare deployment and performance of Open vs commercial energy monitoring systems. Hence Open Energy Monitor which is as of the date of today the most feature-rich Open option, was chosen and some modi_cations necessary for the research scope added. Testing of both aims was conducted as part of the European CIVIS project in Stockholm. 10 houses in Stockholm's F ardala district were used as a test base. Due to logistical and issues related to Open Energy Monitor, Smappee was used as replacement unit. Data obtained with Smappee over the month of July 2015 is analysed in order to validate the assumption that energy monitoring systems have a positive e ect on consumption. Further test results can be obtained from the ndings of CIVIS. As for the second aim, there were indeed a few complications using Open Energy Monitor. The houses tracked in Stockholm are supplied by a 3-phase network and Open Energy Monitor as such was incapable of o ering correct measurements (1-phase works with no issues). The necessary x as well as few other modi cations to Open Energy Monitor, including a multi-user environment are also presented in this report. From all the experiences throughout this project, the resulting modi ed Open Energy Monitor system is more suitable for deployment in user's homes.