Sandia's Tests demonstrate Superior Control Performance of EPC's Grid Connect Systems
In 2013, the HES-RESCU was tested By Sandia National Labs, achieving best-of-field performance.
The full report on the HES-RESCU can be found here:
Five other systems were also evaluated, the results of which demonstrated the superior performance of the HES-RESCU. The as-tested system was fitted with lead-acid batteries for cost reasons, however HES-RESCU is available with various cell configurations, chemistries, and is therefore available with additional stored energy and power ratings.
The full set of Sandia's test reports are available on their web site.