Identifying Efficiency Gaps in Heat Pumps: Sensaru Enables Monitoring of COP and SPF

Karlsruhe, May 14, 2025 – Heat pumps have become standard in new residential buildings: according to HVAC planners, around 81% of newly approved residential buildings in 2024 relied on this technology. The share is even higher in single- and two-family homes, at over 83%. But heat pumps are also becoming increasingly important for property owners of existing buildings.

However, installing a heat pump is just the beginning. Without proper system design and ongoing efficiency monitoring, a heat pump can quickly turn into a cost trap. Mistakes such as incorrect heat load calculations, oversized systems, or lack of hydraulic balancing often lead to inefficient operation—and unnecessarily high electricity bills. Without precise monitoring, these issues often go unnoticed.

"The key question isn’t whether a heat pump is installed—but how efficiently it’s running," says Matthias Zeh, CEO of Sensaru. "Our system makes key indicators like COP and SPF visible and usable during actual operation."

Making Efficiency Visible – Real-Time COP and SPF Monitoring

This is exactly where Sensaru comes in: with a new sensor-based measurement system, the company offers detailed efficiency monitoring during live operation—including the two most important metrics for evaluating heat pumps: COP and SPF

The COP (Coefficient of Performance) indicates the ratio of electrical input to heat output. Sensaru measures this value dynamically across an operating cycle—from compressor start-up to shutdown—providing a realistic performance benchmark. This helps optimize heat curves, hybrid operation modes, and pump settings.

In addition, Sensaru determines the seasonal performance factor (SPF), which reflects the system’s actual efficiency over the course of a full year. Although an SPF of at least 3.5 to 4 is required for public funding applications (e.g. BAFA), this value is usually calculated only in theory. In practice, many systems fail to reach it. While this has no impact on the funding approval, it can significantly increase operating costs. Sensaru not only measures the real SPF—it also helps improve system efficiency and supports continuous monitoring.

How the New Monitoring System Works

Sensaru’s sensor-based system combines the “Heatmeter” (for measuring thermal energy output) with the “S1 Electric Meter” (for monitoring electricity consumption). Together, they enable real-time calculation of key efficiency indicators such as COP and SPF—during actual operation.

This gives property managers valuable insight not just into current performance, but also into the long-term cost-efficiency of their heat pump systems. They can also verify whether the system was correctly designed and detect operational inefficiencies early—before they lead to excessive costs.

The system can automatically detect inefficient conditions such as frequent compressor cycling, electric heater usage, or a drop in performance due to external unit contamination or aging.

Quick Retrofit – No Repeated Inspections Required

Sensaru’s sensors can be retrofitted to nearly all heat pump systems with minimal effort. Both the S1 Electric Meter and Heatmeter are available directly through Sensaru and are designed for easy self-installation—without interfering with existing control technology.

For property managers, technical service providers, or operators of larger portfolios, the system offers a scalable way to digitize and optimize energy performance across their assets. Commissioning takes only a few steps—and can optionally include a legally compliant initial inspection in accordance with § 60a of the German Building Energy Act (GEG).

Another major benefit: the solution meets remote monitoring requirements under current legislation, making repeat inspections unnecessary.

About Sensaru

Sensaru GmbH, headquartered in Karlsruhe, develops intelligent sensor-based measurement systems for the digitalization of heating systems. With easy-to-install solutions and AI-powered data analytics, Sensaru helps real estate companies reduce energy consumption, cut operating costs, and lower CO₂ emissions.

More information: www.sensaru.com

Press contact:

Sensaru GmbH
Natascha Koch
E-mail: Presse@sensaru.com
Phone: +49 7231 123456