German wind power output is expected to drop by 2.7 gigawatts (GW) to 6.2 GW on Thursday, while solar power supply is forecast to fall by 1.5 GW to 5 GW, Thomson Reuters data showed. In France, solar power output is expected to decline by 230 megawatts (MW) to 940 MW.
German baseload power for Thursday delivery rose 5.15 euros, or 20.8 percent, to 29.90 euros ($33.16) per megawatt-hour (MWh), with the equivalent French contract gaining 0.05 euros, or 0.17 percent, to 30.30 euros/MWh.
The data showed that Germany will import 6.5 GW of additional power on Thursday as temperatures rise by 0.5 degrees Celsius and power demand edges 100 MW higher to 68 GW.
In conventional power supply, French nuclear capacity is seen rising by 1.4 GW on Thursday as several reactors ramp up production after a strike on Tuesday reduced output by 2.3 GW.
Power prices along the forward curve fell slightly on Wednesday, tracking coal and carbon prices despite oil gains.
Oil prices rose as traders moved money back into markets hit by the initial shock of Britain's vote to leave the European Union, while a potential oil workers' strike in Norway and a crisis in Venezuela's oil sector also provided support.
German baseload power for next year, the Cal '17, fell 0.06 euros, or 0.23 percent, to 25.85 euros/MWh. The equivalent French contract was down 0.05 euros, or 0.15 percent, at 32.70 euros/MWh.
European coal prices for 2017 fell $0.70, or 1.29 percent, to $53.55 a tonne. Front-year EU carbon allowances dropped by 0.15 euros, or 3.2 percent, to 4.54 euros a tonne.
In eastern European power, the Czech year-ahead position was down nearly 1.5 percent at 26.60 euros/MWh, while the day-ahead price gained 0.3 percent to 33.80 euros.