Here’s the lowdown on the ‘HEMS’
Home energy management systems (HEMS) are rapidly gaining popularity around the world as the technology behind them improves and as small-scale solar power and battery storage become more viable.
But what exactly constitutes a home energy management system? We’ve seen some conflicting descriptions; with this article we aim to bring some clarity to the discussion.
Definition of HEMS
Like anything, the definition of ‘home energy management system’ varies a little bit, especially depending on who you ask! will differ slightly from source to source, but we believe the below neatly encapsulates the concept without being too broad.
‘A home energy management system is a technology platform comprised of both hardware and software that allows the user to monitor energy usage and production and to manually control and/or automate the use of energy within a household.’ (Source: Sustainable Now)
Hardware
A home energy management system’s hardware usually consists of a ‘hub’ device which relays communications between the goings on inside the house, the user and in some cases the local utility or electricity retailer.
This hub is usually installed on the home’s electrical board, but may also be installed ‘virtually’ in cases where the HEMS operates purely on a wireless network. Other, less essential components may include ‘smart plugs‘, light & temperature sensors, and smart devices within the home.
Software
The software used in a HEMS is what moderates the ingoing and outgoing data and communications. From a user’s perspective, the software is the interface that allows access to monitoring data and control functions of the system. The interface usually takes the form of an app or web portal.
The software for some HEMS has the express goal of increasing the energy effectiveness or efficiency of the household, while the focus of others is simply to control devices remotely or automatically for convenience or security purposes.
As for monitoring, the sophistication of the way in which the data is displayed will vary, but will usually include some variation of the below:
- Device & appliance data – Which devices are on and off? How much energy is each one using?
- Granularity of time data – What is the smallest time increment that the system keeps track of – or that it displays to the viewer?
- Insights delivered – Does the system send notifications to tip off the user to trends and issues that they may not pick up on without parsing through the data themselves?
