Page 168 - Fundamentals of Ocean Renewable Energy Generating Electricity From The Sea

Chapter 7

In Situ and Remote Methods for

Resource Characterization

Although wave and tidal energy resources can be either simulated or esti-
mated from various products (e.g. tidal atlases), the resource can only truly
be characterized by direct observation. Whilst observational campaigns are
costly and logistically challenging, such direct measurements can accurately
quantify the resource at high spatial and temporal resolution, and without the
assumptions that are necessary when parameterizing numerical simulations.
In addition, observations are essential for validating numerical simulations
(Chapter 8), which can then be applied to understand processes over longer
timescales or hypothetical scenarios such as sea-level rise or assessing impacts
(preconstruction) of large engineering projects, in addition to investigating
neighbouring regions of interest that have not been directly observed.
In this chapter, we introduce various methods of measuring wave and tidal
resources both in situ and remotely. We describe the principal of some of the
main instruments used to quantify waves and tides, particularly acoustic Doppler
current profilers (ADCPs) and directional wave buoys. We also discuss ship-
based sampling techniques (e.g. sea-bed sediment grabs and water column pro-
filing), and remote-sensing technologies, including X-band and high-frequency
(HF) radar.

7.1 TIDAL ENERGY RESOURCE CHARACTERIZATION
Desk-based studies can provide useful information about the tidal energy
resource of a region. Tidal atlases, such as the ABPmer Atlas of UK Marine
Renewable Energy Resources [1], and the NREL Atlas of Marine Renewable
Resources in the US, provide information on the spatial distribution of depth-
averaged spring tidal currents, albeit at relatively coarse resolution. More
detailed regional studies in the peer-reviewed academic literature provide ad-
ditional information on tidal streams (e.g. [2]), and articles that are open access
are particularly useful to those working outside academia (e.g. [3]). Examination
of Admiralty Charts provides further, detailed, site-specific information, such as
the distribution of bathymetric contours, tidal range, and spring and neap current
speeds (and directions) in more detail than tidal atlases, at specific points known
as tidal diamonds (e.g. Table 7.1).
Fundamentals of Ocean Renewable Energy. https://doi.org/10.1016/B978-0-12-810448-4.00007-0
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