Power System Optimization

A method set point determining device and computer program product for determining set points of machines, energy storage units, wind generators and/or solar panels in a power system. The set point determining device includes an efficiency curve determining unit configured to determine, during operation of the power system, current individual efficiency curves of machines, energy storage units, wind generators and/or solar panels, each curve defining the efficiency of the corresponding machine, energy storage unit, wind generator and/or solar panel, where a current efficiency curve is obtained as a real-time estimation using current and historic power system data, and an optimization handling unit configured to, at a point in time of power system control, form a function including a first expression, which is a sum of products, each product including the power of a machine, energy storage unit, wind generator and/or solar panel times the individual efficiency of the machine, energy storage unit, wind generator and/or solar panel obtained from the corresponding current individual efficiency curve, determine a power demand of the system, optimize the function subject to the condition that the sum of powers of the machines, energy storage units, wind generators and/or solar panels reach the power demand, determine desired set points of the machines, energy storage units, wind generators and/or solar panels based on the optimization and supply the set point to the machines, energy storage units, wind generators and/or solar panels.