More than 1,000 customers are now participating in the trial, building on the insights gained from the initial stage.
In the first trial, 386 households engaged in intermittent heat pump shutdowns for two-hour periods, resulting in a total measurable turndown of 10.8MWh.
This demonstrated the potential of heat pump flexibility to contribute to energy savings and ease the strain on the electricity network during peak periods.
Matt Watson, Head of Commercial and Operability at National Grid DSO, said: “The initial results from our EQUINOX trials show that heat pump flexibility can help manage the demand on electricity through the distribution network while simultaneously saving customers money on their energy bills.
“Feedback from participants so far have shown that these kind of flexibility measures do not compromise the comfort of households and that the customer experience was positive.”