The market value of gas storage is to a large extent determined by the summer-winter spread of gas prices. In recent years these spreads have fallen to levels where some storage operators/owners are struggling to cover their annual operating costs. This has contributed to 8 bcm of capacity being closed or mothballed in Europe since 2010, despite overall capacity in the region growing by 18 bcm. Wood Mackenzie has carried out some sensitivity analysis, reducing storage capacity by 25% in north west Europe to see what the impact on price spreads might be. We have also assessed what the price impact of a particularly cold winter might be under these conditions.