Net metering

"A net metering scheme is provided in the Renewable Energy Law, giving capable consumers the option to generate their own power, which in turn will give them the possibility of being paid by their power distributor or given discounts for the power they give back to the grid.
Net metering uses a special electricity meter, which is bi-directional — meaning the meter spins forward if more electricity is used than provided back to the grid, and backward if there is more electricity provided than used." - Ava Kashima K. Austria, Businessworld