1
Grid surplus electricity
When the grid has more power than it needs, prices fall and the system is paid to absorb that surplus as stored heat.
2
Rooftop solar surplus
Midday solar peaks your building can't use are captured on site and stored, instead of exported for almost nothing.
3
Electricity to heat
That surplus electricity is converted into heat and charged into the borehole store in the bedrock beneath the building.
4
Seasonal heat store
The bedrock holds the summer's heat for months, then returns most of it in winter, around 80% of what was stored.
5
Winter heat, summer cooling
Months later the store heats the building right through winter and cools it in summer, one asset for the whole year.