Marine energy converters will require the implementation of control strategies to achieve viability in some cases and maximise profitability in most. These control strategies may require distributed information on the wave field in which the device resides. A novel method of obtaining this data is investigated using a lattice of treated optical fibres constrained on a flexible substrate and fitted with floatation aids. By measuring the intensity of light lost at bends along its length the patented device, Shape TapeTM, can sense its position in three dimensions. Preliminary tests involving JONSWAP spectra, generated in a 20 metre long, 0.7 metre deep two-dimensional wave flume, show the flexible ribbon predicts Hm0 and Tm01 with errors less than 16% and 9% respectively when compared to wave gauge measurements. Repeatability tests using regular wavetrains provide standard deviations away from the results of wave gauges of 5% in wave height and 1% in wave period.