The practically extractable tidal stream resource available in UK waters (including the Channel Islands) is between 20 and 30TWh per year. This is roughly the equivalent of the energy used annually by approximately 7 million households equating to between 6% and 8% of UK's electricity demand!
Much of the UK coal fired capacity is expected to be withdrawn from service over the next two decades. Since no fossil fuels are consumed directly by power production from tidal energy plants, replacing coal fired capacity with tidal stream capacity will reduce carbon dioxide emissions.
DECC figures indicate that coal fired plants supply 30% of the 368 TWh of electricity generated in the UK annually and in the process released 335 million tonnes of CO2.
So, harnessing the UK tidal stream resource could supply 8% of UK electricity demand. If we managed to do that we could replace the equivalent coal fired generation, which would avoid 88 million tonnes of CO2 emissions per year
Why tidal? It just makes sense!