World Energy Resources | 2016

WORLD ENERGY COUNCIL | WORLD ENERGY RESO URCES 2016
where there is a significant phase difference between the tides that flow on either side of
large islands’ 7 .
It is difficult to identify reliable estimates for global tidal stream energy potential but Charlier
& Justus (1993) estimate total tidal energy potential (i.e. tidal range and tidal stream) at 3
TW, with 1 TW located in relatively shallow waters. However, due to geographical, technical
and environmental constraints only a fraction of this could be captured in practical terms. In
practice, suitable locations need mean spring peak tidal currents that are faster than 2-2.5
m/s to offer an energy density that allows for an economically viable project, 8 accounting for
the fact that as the tide changes there will be little or no horizontal flow of water. 9
Importantly, ‘major tidal streams have been identified along the coastlines of every
continent, making it a global, albeit site specific, resource’ 10 . For example, at the European
level 106 locations with a strong tidal stream potential were identified, together offering 48
TWh/yr (0.17 EJ/yr) of potential resource 11 . A similar study examined Europe’s tidal stream
potential identifying that it was predominantly concentrated around the British Isles and
English Channel 12 (Figure 2).
FIGURE 2: EUROPEAN TIDAL STREAM RESOURCE DISTRIBUTION (AQUA-
RET 2012)
Source: Aqua-RET (2012)
7
Aqua-RET (2012)
8
Aqua-RET (2012)
9
Mofor et al. (2014)
10
Mofor et al. (2014) p.4
11
CEC (1996)
12
Aqua-RET (2012)
9