what are the problems with tidal electricity generation?

Answer 1

The French seem to have been most successful with a barrage across an estuary - that generates power as the tide comes in and out. Obviously, it's not generating all the time and so the power needs to be stored. The costs of building the system are high too. New ideas include floating generators on the sea that take advantage of the currents and tide. With a turbine under water - but getting the power back to shore isn't easy. Platforms like oil rigs at sea are also being experimented with and even wave power and linear type alternators. The generation of power using nuclear 24/7 and then using the power off peak to pump water up to a high reservoir - then using that water to drive turbines at peak times seems more economical until the problems can be sorted out. But the amount of energy available in the sea is enormous and renewable.

Answer 2

Peter Bungard CEO of Glos CC held a seminar on renewables at Stonehouse which included tidal power, specifically dealing with the Severn Estuary and Bristol channel, the 2nd greatest Tidal range in the world at 40 feet.
the french Barrage was mentioned, but it is silting up as is one in Canada, It is not sustainable.
Off shore water turbines seem a better bet, placed at intervals along the southe coast they could be arranged to provide power in sequence as the tides move round one at Dover would be at full power as one at plymouth was stalled as the tide turns, The Severn Estuary itself would silt up if a barrage were built, the ecology of the Severn would be seriously damaged, and there would be dead periods at high and Low tide when no power would be generated and Electricity is very hard to store, and forms of generation which can be quickly started and stopped such as Gas Turbine and Diesel are the worst in terms of pollution and CO2 emisions per KwH, Small scale river power with water mills are nt capable of producing much power and the old desilting methods used by 18th century miller would not be acceptable in the 21st century.
Offshore Wind Turbines mounted above tide turbines have been mooted but the promising tide turbine off the coast near Lynmouth has never been connected to the mains, despite green pretensions the Government has no interest in renewables.and ther are no funds for cabling.
Many Wind Turbines will not pay their energy or Co2 costs in their lifetime, even in Wale, windiest place in Europe the 36 % efficiency ( like if they were 1 Mw they would produce 365 Mw days per year if the wind bkew hard enough yet they actually priduce 130 Mw days) is a fiddle factor as the turbines are only rated at 75% of max outrput so efficiency is down around 27% and many German and Belgian ones only achieve 5 % these took more Co2 to make and install than they will save over their lifespan, they will make fat profits but do harm to the visual environment and increase global warming.
Iidal power has limited use but Nuclear Power is clearly the safest sustainable answer as Co 2 emissions are negligable,

Answer 3

Let me be frank.....

Don't mind all this bollox about people saying that it will affect the earth in this way and that, and how it would take too much work input to actually make the energy useful!The fact of the matter is that whilst engineers and scientist's can research to their blue in the face the powers that be can't think outside the box and beyond the cash factor. Burning of fossil fuels will kill us one million times over before a slowing of the earths rotation would come close to affecting us....The sad fact of the matter is that fossil fuels are the done thing, capital is majorly invested in this business and the investors have their hands in the pockets of the people with the power to make this happen......That my friend is the only problem with Tidal elec generation and the same goes for wind and solar alike......

Answer 4

nobody wants to invest?