Sound emission measurement and frequency analysis for battery storage systems (BESS)
Sound emission measurement for battery storage: we measure the noise level of your battery system and deliver reliable data for operation.
Battery storage systems are not silent either. Our measurements capture the noise level of your plant reliably. This lets you assess noise emissions objectively at any time, meet legal requirements and plan the operation of your storage efficiently. The main noise source is usually the battery cooling fans. Added to this is the electrical hum of transformers and inverters and, in larger plants, the grid connection transformer. The level can depend on the operating state, for example load and cooling. For this reason, operating conditions and operating modes are part of every measurement, and a reduced operating mode is reported separately. Measurement points, photos and plans should be documented transparently so that authorities and experts can verify the results. With many units, the levels add up. Possible noise control measures include turning the fans towards the side facing away from the residential area, solid noise barriers close to the containers and additional walls between container rows. For modifications to existing plants, the total emission from the existing plant and the modification must be considered, and the insulation values of enclosures must be substantiated with a data sheet or test report.
Frequency analysis complements the overall level with the spectrum. A narrow-band analysis shows whether individual tones such as a hum or a whine stand out from the noise. Tones are perceived as more disturbing than broadband noise of the same loudness, which is why assessment methods provide penalties for them. Octave and third-octave filters are usually too coarse for assessing tonality. If a dominant tone appears, for example at the fan frequency, it can be reduced in a targeted way, for instance with tuned silencers.
In the permitting procedure, the forecast examines the operating states and assessment periods relevant to the site and the permit, and after commissioning an acceptance measurement checks whether the forecast values are met. The immission is assessed under the rules applicable at the site and in the procedure; in Austria, the locally prevailing sound immission may be described by the base level L_A,95, and the core night period may have to be considered separately. To this end, we develop site-specific measurement concepts and measure with up-to-date calibrated equipment in accordance with internationally recognised standards. We record the result in standard-compliant test reports. We coordinate with the manufacturer technically and solution-oriented, on an equal footing, and you receive concrete, practical recommendations for optimisation. If the forecast values are not met, improvements are necessary, for example additional noise barriers.
In Austria, ÖNORM S 5004 describes the measurement of sound immissions, ÖNORM EN ISO 3746 and 3747 the determination of sound power levels, and propagation to the immission point is forecast with ÖNORM ISO 9613-2. The forecast is provided by the operational noise assessment for battery storage, while the sound immission measurement records the existing sound load at the immission point. After construction, the technical acceptance follows. We also offer the measurement for PV plants.
