Can energy monitoring be retrofitted into a commercial building? Learn the best solutions, wiring methods and energy-saving strategies.
Commercial buildings are under increasing pressure to reduce energy consumption, lower operating costs and demonstrate measurable sustainability improvements. Yet many facilities managers still lack visibility into where energy is actually being used.
The good news is that modern energy monitoring systems can now be installed in almost any commercial property without major rewiring or disruptive refurbishment work.
Using DIN-rail mounted energy meters, current transformers (CT clamps) and smart monitoring platforms, electrical contractors can deliver real-time visibility into energy consumption across offices, retail spaces, schools, warehouses, healthcare facilities and hospitality venues.
While energy monitoring does not directly reduce consumption, it provides the data needed to identify inefficiencies, support energy retrofit projects and measure the impact of energy-saving improvements over time.
Can energy monitoring be installed in an existing commercial building?
Yes.
Modern energy monitoring solutions are specifically designed for installation in existing buildings and distribution boards. Devices such as the Shelly PRO EM-50 and Shelly PRO 3EM can be installed using CT clamps that fit around conductors without cutting, disconnecting or modifying existing wiring.
This allows contractors to monitor energy consumption at circuit level while minimising disruption to building operations.
For many projects, installation can be completed during routine maintenance periods without affecting day-to-day business activities.
Why install energy monitoring in a commercial property?
Most commercial buildings only have visibility of total energy consumption through utility bills or a main incoming meter.
This makes it difficult to understand:
Which systems consume the most energy
When peak demand occurs
Whether energy-saving measures are working
Which equipment is operating inefficiently
How different areas of a building compare for energy use
By introducing circuit-level monitoring, businesses can:
Reduce energy waste
Improve operational efficiency
Support ESG and sustainability reporting
Identify equipment faults earlier
Verify return on investment from energy-saving projects
Enable automated energy management strategies
Energy monitoring provides the data needed to make informed decisions about building performance. When combined with automation and control, it becomes a powerful tool for identifying opportunities to reduce energy consumption and operating costs.
How does energy monitoring support energy retrofit projects?
Energy monitoring is often the first step in a successful energy retrofit programme.
While monitoring devices do not directly improve energy efficiency, they provide the visibility needed to identify where improvements can be made and which systems should be prioritised.
For example, energy monitoring can help identify:
Lighting circuits consuming excessive energy
HVAC systems operating outside business hours
Equipment with unusually high power demand
Peak demand periods driving energy costs
Opportunities for automation and load management
Once retrofit measures have been implemented, the same monitoring platform can be used to verify savings, demonstrate return on investment and measure long-term performance improvements.
For building owners and facilities managers, this creates a clear link between energy data and measurable business outcomes.
What equipment is needed to install energy monitoring?
The exact solution depends on the building and application, but most commercial installations consist of:
Energy monitoring devices
Current transformers (CT clamps)
DIN-rail installation within the distribution board
Network connectivity
Energy management software
Shelly's professional energy monitoring range provides solutions for everything from individual circuits through to complete three-phase commercial installations.
Shelly PRO EM-50
The PRO EM-50 is designed for accurate single-phase and smaller commercial monitoring applications.
Ideal for:
Retail units
Restaurants
Small offices
HVAC equipment
Individual distribution circuits
The device delivers real-time power measurement, consumption monitoring and historical reporting through the Shelly app, allowing facilities teams to monitor energy use remotely and identify opportunities for improvement.
Shelly PRO 3EM
For larger commercial and industrial environments, the PRO 3EM provides advanced three-phase energy monitoring.
Typical applications include:
Office buildings
Warehouses
Manufacturing facilities
Hospitality venues
EV charging infrastructure
Renewable energy systems
The device enables businesses to monitor consumption across multiple phases while providing detailed data on power quality, import and export energy flows and overall building performance.
Shelly PRO 3EM Switch Add-on
Monitoring alone identifies opportunities. The PRO 3EM Switch Add-on enables contractors to turn those insights into automated actions.
By combining monitoring with load control, businesses can:
Disconnect non-essential loads during peak demand
Prevent overload conditions
Automate load shedding
Optimise energy usage based on real-time consumption
Shelly PRO 4PM
The PRO 4PM combines monitoring and control across four independent channels from a single DIN-rail device.
This makes it particularly effective for:
Lighting circuits
HVAC zones
Commercial plant equipment
Load management projects
By providing both energy measurement and remote switching, it enables facilities teams to identify waste and take corrective action immediately.
How is commercial energy monitoring installed?
Most projects follow four straightforward steps.
Step 1: Identify critical loads
The highest-value monitoring opportunities are typically:
HVAC systems
Lighting circuits
Refrigeration equipment
Pumps and motors
EV charging infrastructure
Tenant sub-metering applications
Step 2: Install monitoring devices and CT clamps
Energy monitoring devices are installed within the distribution board while CT clamps are positioned around conductors to measure current flow.
Because the conductors remain intact, installation is considerably less disruptive than traditional metering solutions and is well suited to occupied commercial environments.
Step 3: Connect to the monitoring platform
Once installed, energy data can be visualised through the Shelly app and cloud platform.
The platform enables users to:
Monitor live energy consumption
Track historical trends
Compare building performance
Identify abnormal energy usage
Receive alerts and notifications
Generate energy reports
Manage multiple sites from a single dashboard
For organisations managing multiple locations, the Shelly platform provides centralised visibility across entire property portfolios, helping identify inefficiencies and prioritise future energy-saving investments.
Step 4: Create automation and energy-saving strategies
The greatest value comes when monitoring data is used to support energy management.
Examples include:
Switching off equipment outside operating hours
Reducing HVAC demand during peak tariff periods
Load balancing EV charging infrastructure
Automating lighting schedules
Preventing demand spikes
Managing loads based on real-time consumption
This transforms energy monitoring from a reporting tool into a practical energy management solution.
Commercial energy monitoring wiring guides
For contractors looking to deploy commercial energy monitoring solutions, Shelly provides practical installation resources and wiring guides.
Shelly PRO 3EM wiring guide
The Shelly PRO 3EM is designed for three-phase monitoring applications and can provide detailed visibility of energy consumption across commercial premises.
Watch the installation guide:
Shelly PRO EM-50 wiring guide
For smaller monitoring projects and individual circuits, the PRO EM-50 offers a straightforward route to accurate energy measurement.
Watch the installation guide:
Always follow manufacturer instructions and local electrical regulations when installing energy monitoring equipment.
Frequently asked questions
What is the best way to monitor energy usage in a commercial building?
The most effective approach is circuit-level monitoring using dedicated energy meters and CT clamps. This provides detailed visibility into where energy is being consumed rather than relying solely on utility billing data.
Can energy monitoring be installed without rewiring?
Yes. Modern energy monitoring systems use CT clamps that fit around existing conductors, eliminating the need for significant rewiring in most installations.
What is the difference between energy monitoring and an energy retrofit?
Energy monitoring measures and records how energy is being used within a building.
An energy retrofit involves making improvements that reduce energy consumption, such as upgrading lighting, introducing automation, optimising HVAC systems or implementing load management strategies.
Energy monitoring helps identify retrofit opportunities and provides the data needed to measure their effectiveness.
How can businesses reduce energy consumption using monitoring data?
Monitoring identifies inefficiencies such as equipment running outside operating hours, excessive HVAC demand or unnecessary lighting usage. Automation and targeted improvement projects can then be implemented to deliver measurable savings.
How does the Shelly app support commercial energy management?
The Shelly app enables facilities managers, contractors and building owners to monitor, measure and control energy usage from anywhere. Users can view live consumption data, analyse historical trends, receive alerts, generate reports and automate actions based on energy consumption patterns.
Using energy monitoring to support energy retrofit projects
Energy monitoring is often the first step towards a smarter and more efficient commercial building.
Alongside dedicated monitoring devices such as the PRO EM-50 and PRO 3EM, contractors can integrate a wider range of Shelly solutions including smart relays, lighting controls, load management devices and environmental sensors to create a complete energy optimisation strategy.
From monitoring HVAC consumption and controlling lighting schedules to managing peak demand and automating energy-intensive equipment, a connected ecosystem can help identify opportunities for energy savings while improving operational efficiency.
For electrical contractors, energy monitoring represents one of the most accessible routes into smart commercial building projects. For businesses, it provides the visibility required to make informed decisions, prioritise energy retrofit investments and measure the impact of efficiency improvements.
Combined with the Shelly app and wider range of smart monitoring and energy-saving solutions, organisations gain a complete view of their energy usage while unlocking opportunities to reduce waste, lower costs and improve sustainability performance.