Energy Monitoring + Submetering (e.g. EDM Toolbox)

Building an energy capture system with sub-meters per consumer or zone and continuous monitoring — the data foundation for every further measure.

How does energy monitoring with sub-metering work?

Energy monitoring records a building's energy flows continuously rather than only once a year via the utility bill. Its foundation is sub-metering: in addition to the main meter, sub-meters are installed for individual consumption circuits, such as heating, cooling, ventilation, lighting, processes or individual tenant areas. Electricity, heat, gas and water are recorded via meters with M-Bus, Modbus or S0 interfaces. A gateway collects the readings, usually at 15-minute intervals, and transmits them via the data network or mobile network to an analysis platform. There, load profiles, period comparisons, key figures per area or use, and alarms for deviations are generated. The principle is simple: no measurement, no optimisation. Only the breakdown by consumption circuit reveals where base loads run at night, which plant draws energy outside occupancy hours and whether an implemented measure is actually working.

Which buildings benefit from energy monitoring?

The measure is suitable for all larger buildings and estates, from office buildings and production sites to branch networks and municipal portfolios. The prerequisites are meter-side interfaces (M-Bus, Modbus or S0) and a data connection; there are no exclusion criteria. The benefit is particularly high in buildings without active facility management, because that is where most unnoticed consumption occurs. For companies with an energy management system to ISO 50001, monitoring is a mandatory component anyway: savings must be demonstrated by measurement, not merely estimated. Energy audits to EN 16247-2 also rely on robust consumption data.

What does energy monitoring actually deliver?

Consumption transparency alone typically leads to 5 to 15 % savings, because faulty operation, unfavourable time schedules and creeping excess consumption become visible and can be corrected on an ongoing basis. The saving factor is around 3 % for well-managed buildings and up to 15 % for buildings without facility management. An office building with 750,000 kWh/a total consumption saves around 60,000 kWh/a with the standard factor of 0.08. Investment for a gateway and 5 to 10 sub-meters is €3,000 to €12,000, plus platform costs of €50 to €300 per month. Payback is 1 to 3 years. The real value goes beyond that: every further measure, from building automation to a PV system, only becomes plannable and verifiable with measured data.

Energy carrier

Erdgas, Heizöl, Fernwärme, Strom → Erdgas, Heizöl, Fernwärme, Strom

Savings potential

5-15 % allein durch Transparenz; ermöglicht weitere Maßnahmen

Worked example

An office building with 4,000 m² of usable floor area consumes 750,000 kWh of energy per year across all energy carriers, so far measured only via the utility's main meters. The operator installs a gateway and sub-meters for heating, ventilation, cooling, lighting and the server rooms, making every consumption circuit visible at 15-minute resolution. To estimate the saving, the standard monitoring factor of 0.08 is applied, which corresponds to an averagely managed building. The calculation is: 750,000 × 0.08 = 60,000 kWh/a. These roughly 60,000 kWh/a result purely from transparency and ongoing correction of faulty operation, such as ventilation outside occupancy hours or night-time base loads. In addition, all follow-up measures can be verified against the measured data, which is decisive for audits and ISO 50001.

Investment & payback

Gateway + 5-10 Subzähler: 3.000-12.000 €; Plattform-SaaS (EDM Toolbox) 50-300 €/Monat · Service life: 12 a · Payback: 1-3 a

Applicability

Requirements

Typical buildings

Frequently asked questions

What is the difference between energy monitoring and sub-metering?

Sub-metering refers to the installation of sub-meters that record the consumption of individual areas or plant separately from the main meter. Energy monitoring is the continuous evaluation of these readings in software: load profiles, key figures, comparisons and alarms. Sub-metering provides the data; monitoring turns it into insights. Together, they form the basis for energy management to ISO 50001.

How much does energy monitoring save in a building?

Consumption transparency alone typically yields 5 to 15 % savings. For a well-managed building the factor is around 3 %, for a building without facility management up to 15 %. An office building with 750,000 kWh/a total consumption saves around 60,000 kWh/a with the standard factor of 8 %. The saving comes from identifying and eliminating faulty operation and unnecessary base loads.

How much does an energy monitoring system cost for a commercial building?

A gateway with 5 to 10 sub-meters costs €3,000 to €12,000 to purchase. On top comes the analysis platform as a software subscription at €50 to €300 per month, depending on the number of meters and the feature set. With a payback of 1 to 3 years and a service life of 12 years, energy monitoring is one of the most economical efficiency measures of all.

Is energy monitoring mandatory for ISO 50001?

Yes, an energy management system to ISO 50001 requires systematic recording and monitoring of energy consumption and measurement-based verification of savings via energy performance indicators (EnPIs). Without sub-metering and continuous monitoring this cannot be achieved. Energy audits to EN 16247-2 also rely on robust consumption data per consumption circuit.

Which meters do you need for sub-metering?

Meters with a digital interface are suitable for sub-metering: M-Bus and Modbus for electricity, heat, gas and water meters, or an S0 pulse output on simple meters. Many existing meters can be retrofitted with reading modules. A gateway for data collection and a data connection via network or mobile network are also required. A dedicated meter per consumption circuit, such as heating, ventilation or lighting, is advisable.

Related measures

Standards & sources

Metering points in the EDM Toolbox

Das ist DIE Kernanwendung der EDM Toolbox. Hier lässt sich der Wert von LineMetrics direkt argumentieren: aufwandsarme Sensorik, Mobile App, Plattform für Visualisierung und Energiebuchhaltung.

All measures