Analysts often divide wind power projects into two categories: onshore and offshore. A third category recently emerged: nearshore projects, built on the intertidal flats. We observe a quasi cross-sectional sample of Vietnam's wind power projects, exhaustive regarding projects at the operating and building stages, comprising projects in the three categories. The median investment for onshore wind power projects in Vietnam is 1 680 USD/kW. It is 2 174 USD/kW for nearshore projects. We computed the relative extra investment distribution for intertidal projects compared to onshore projects in our sample. On average, a MW of generation capacity requires about 50% more investment nearshore than onshore. But variation is considerable, the interquartile range 20%-70% represents the extra cost better. It does not follow that electricity from nearshore stations costs more. Annual generation depends on the capacity factor. Projects developers are paying extra for better wind nearshore.