As of 2020 costs for offshore wind power stations is the lowest cost of any other UK electricity generation, less than 50% of the cost of Nuclear Power (before balancing/storage costs). Three reports on the wind variability in the United Kingdom issued in 2009, generally agree that variability of the wind does not make the grid unmanageable; and the additional costs, which are modest, can be quantified. For wind power market penetration of up to 20% studies in the UK show a cost of £3-5/MWh. In the United Kingdom, demand for electricity is higher in winter than in summer and so are wind speeds.