Control of combined heat and power plant (CHP)

What is service E-5?

Service E-5 is part of the Electricity domain within the Smart Readiness Indicator (SRI). This service assesses how intelligently a building controls its combined heat and power installation. A combined heat and power installation, also called CHP, produces electricity and heat simultaneously.

The SRI is a European measurement method that expresses a building's smart capacity as a score. This score is built from 54 smart-ready services across 9 domains. E-5 does not count toward the shortened method A, only toward the full method B.

What functionality levels does E-5 have?

This service has three levels, numbered 0 through 2. Each level describes one step in how the CHP installation is controlled.

• Level 0: the CHP operates according to a fixed schedule or responds to current heat demand in the building.
• Level 1: operating hours are adjusted to changing availability of renewable energy sources. Excess production flows back to the electricity grid.
• Level 2: control takes into account both renewable energy sources and grid signals. Load and operating hours are managed dynamically to maximize on-site use of renewable energy.

Each level is assessed against seven impact criteria, such as energy efficiency and grid flexibility. These criteria each have their own weighting factor in the class calculation.

Why does this service count toward the SRI score?

The SRI does not look only at installations themselves, but at the intelligence of their control. A building with a CHP installation that responds to grid signals contributes to a more stable electricity grid.

This aligns with the broader objective of the EPBD, the European Energy Performance of Buildings Directive. Building automation is being introduced stepwise in that Directive: first above 290 kW, later also above 70 kW of HVAC capacity.