OpenEMS
OpenEMS: A free, open-source platform for monitoring and controlling distributed energy assets. Ranked #17 of 25 in Energy Management Software by our editors (7.2/10); pricing: Free plan; best for open-source energy asset control.
At a glance
- Editor score7.2 / 10
- PricingFree plan
- Best forOpen-source energy asset control
- Free planYes
- Paid fromFree
- Energy monitoringPortfolio
- Founded2016
- Facts checked22 Sep 2026
Where it wins
- Free and open source with self-hosted deployment
- Real-time monitoring and on-site device control
- Broad protocol support with storage, renewables and EV charging
Where it doesn't
- Self-hosting places deployment responsibility on the operator
- The platform spans many systems and may require technical integration work
- Commercial products based on OpenEMS may have separate pricing
Our verdict on OpenEMS
OpenEMS is a modular, open-source energy management platform for monitoring, controlling and integrating energy storage with renewable generation and other devices. It is suited to private, commercial, industrial, research and energy-transition applications, including batteries, electric-vehicle charging, heat pumps and electrolysers. The stack combines OpenEMS Edge for on-site device communication and control, a web UI for live and historical views, and an optional Backend for connecting and aggregating decentralized Edge systems.
OpenEMS is presented as free and open source, with self-hosted deployment across web and API environments. Its published capabilities cover portfolio energy monitoring, forecasting, automated utility data import and API access. The platform also supports time-of-use electricity tariffs, which helps address systems where operating decisions depend on changing electricity costs. There are no separate paid tiers described here; commercial products based on OpenEMS may have their own pricing. This structure fits teams that want control over deployment and the ability to adapt the platform rather than buy a packaged subscription.
Integration breadth is a central strength. OpenEMS supports REST, WebSocket, MQTT, Modbus and JSON interfaces, alongside integrations such as InfluxDB, OCPP, M-Bus and 1-Wire. Its device- and protocol-independent control algorithms are designed to connect varied energy assets, while storage, renewable generation and EV charging can be coordinated in one system. That breadth makes OpenEMS a strong choice for technically capable operators managing diverse or decentralized assets. Organizations seeking a fully managed product with a simpler operational model should consider alternatives, while teams prioritizing open-source control, local operation and extensibility are its clearest audience.
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OpenEMS pricing
OpenEMS fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Free |
| Energy monitoring | Portfolio |
| Energy forecasting | Yes |
| Carbon tracking | Not verified |
| Utility data import | Automated |
| Data retention | Not verified |
| API access | Yes |
| Deployment | Cloud, Self-hosted, Browser extension |
| Platforms | Web |
| Support | Email, Community, Docs |
| Built for | Small business, Mid-market, Enterprise (editorial estimate) |
| Integrations | 9 integrations: InfluxDB, MQTT, Modbus/TCP, Modbus/RTU, JSON/REST, JSON/WebSocket … See all → |
| Pricing | Free plan |
| Website | openems.io |
| Facts checked | 22 Sep 2026 |
OpenEMS integrations
OpenEMS lists 9 integrations on its own site.
- InfluxDB
- MQTT
- Modbus/TCP
- Modbus/RTU
- JSON/REST
- JSON/WebSocket
- OCPP
- M-Bus
- 1-Wire
See all OpenEMS integrations →
Alternatives to OpenEMS
- ABB NsightA portfolio-focused platform for monitoring, reporting, forecasting, and energy optimization.9.2
- Johnson Controls OpenBlue Net ZeroA broad portfolio platform for utility data, emissions tracking, forecasting, and reporting.9.1
- Siemens Industrial Energy ManagementA broad industrial portfolio for monitoring, benchmarking, and optimizing energy across complex sites.9.0
See all OpenEMS alternatives →
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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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