January 29, 2024

Home Energy Management System (HEMS)

A Home Energy Management System, or HEMS, is a digital system that monitors and controls energy generation, storage and consumption within a household. HEMS usually optimizes for a goal such as cost reduction, self-sufficiency maximization or emissions minimization. With the increasing adoption of electric mobility and heating, residential PV, and dynamic tariffs HEMS are becoming more popular as the saving potential increases.

Typical assets

  • Photovoltaic (PV) - A PV system, or rooftop solar, is often the first step to a HEMS as it allows households to become independent from the grid (and increasingly volatile electricity prices) and use locally-generated electricity to power the energy-consuming assets in their home. These usually include an inverter to convert the solar power into usable energy that powers household devices.
  • Battery - a storage system can store surplus solar power when the sun is shining and allows it to be used later when it is needed. 
  • Heat pump - a heat pump is a highly efficient heating device powered by electricity that extracts heat from an external source rather than producing it. It can be powered by local PV and is therefore becoming an increasingly common part of HEMS.
  • Electric vehicle (EV) -  EVs are another flexible energy-consuming asset. Because they usually sit for a long period of time, their charging can be shifted to periods when either solar generation is high or electricity prices are low. The car must be linked to the HEMS via a wallbox or other smart EV charger. 
  • Smart meter - a smart meter is an important element in a HEMS as it provides real-time information on household consumption
  • White goods - household devices such as washing machines or fridges can also be controlled intelligently to optimize their electricity consumption.
different types of assets for home energy management system

Technical requirements

To implement a HEMS, there are certain technical requirements that must be met, to ensure seamless and consistent functioning of different distributed energy resources (DERs);

  • A stable and reliable internet connection securing proper communication between the energy management system (EMS),server and each energy device would be beneficial but a local network would suffice
  • A local gateway typically in the form of a central control unit, like our gridBox, that optimizes energy flows on site. Cloud-based energy management is also possible without a local gateway, however, this is less prevalent and has increased latency.
  • Software and applications compatible with the hardware to control, monitor and access the DERs in a household.


The goal of a home energy management system is to cover the energy demand of a household while minimizing costs and/or emissions. Typically, a HEMS reduces costs and emissions by maximizing the utilization of renewable energy  as it aligns consumption with times when renewable energy is available.

what is the goal of home energy management system.png

Use cases

Every household has its individual needs. Thus the use cases and applications may vary to fit specific demands. Home Energy Management Systems can start with a basic setup involving a few assets and then become more complex to enable more savings.

  • Monitoring – gaining real-time data and visualization of the operational behavior, site-specific details and status of all connected assets.
  • Self-sufficiency optimization – maximizing the amount of self-generated power that is used to power the remaining assets in a home to minimize costs and emissions.
  • Time-of-use tariffs (ToUT) – shifting the electricity consumption of  connected DERs, such as heat pumps and electric vehicles, to times of low prices.
  • Flexibility Marketing – monetizing the flexibility of assets by feeding energy back into the grid if there is excess power, for example stored in the battery, according to varying electricity prices and grid capacity.
  • Larger use cases - HEMS is the building block that enables larger-scale future energy use cases such as smart districts (energy is connected and optimized across a larger area), virtual power plant (the flexibility of multiple energy assets is aggregated and monetized by participating in wholesale markets) or energy communities (energy is shared via peer-to-peer trading).