Soldato
- Joined
- 21 Oct 2011
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- 22,370
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- ST4
Probably all too busy keeping their AGAs fired up and drinking their soy lattes.
"Just stop oil"
- Thread starter Diddums
- Start date
Hydrogen storage is really not viable for energy storage tbh. It's extremely difficult to keep contained and has an extremely low density, requiring enormous storage tanks to hold any real volume - unless you go cryogenic and store it as LH2, but that is even trickier to handle.
The "real" solution to nuclear power would have been appropriate research into Thorium based reactors so they are self-arresting, which hugely negative temperature coefficients to the point where they will physically self-arrest any potential meltdown long before it actually happens.
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Tides may be predictable but they are far from consistent. The height of the tide, which directly affects both the throughput and speed of a given channel of water can be wildly different one day to the next, so just like with wind, it's very difficult to design a turbine-based system that can handle all those varying ranges.
This is why so often at higher winds turbines are set to "weathervane" and the blades turned 90degrees so they get no rotation, it's to protect the equipment. That's the biggest issue Wind and Tidal has, as the available power increases their ability to withstand it decreases rapidly.
The other issue with estuary-based tidal power is that the tide is only really at "full flow" in or out for a couple hours at most, either side of high / low tide, so you won't get anything close to maximum generating capacity for around 70% of the day.
Tides are totally predictable! They have a spring-neep cycle when the sun and moon combine to increase tide height or reduce it, but you only need to look at tide tables to see how predictable tides are. Atmospheric pressure can influence sea levels, but the tidal flows are predictable. A 10mile tidal barrage in the Severn Estuary could produce 5% of the UKs power needs for example.
You are totally right that very little energy will be produces at slack tides, energy storage is also key, Dinorwig is a great example of large scale storage - or more batteries at a local level. But don't forget tide times vary around the whole UK. For example when Cardiff has a high tide at 19:12 today, John O'Groats has a high tide at 22:14 which would fill in the slack at Cardiff perfectly.
Tidal power is no where near as mature as wind/solar but is a great potential resource. But all are a better option than fossil fuels.
Like I said, they are predictable, but not consistent...
Tide tables tell you nicely when high tide / low tide will be etc.. but even then we still quite regularly get "freak tides" which are higher than expected, or we get an onshore wind pushing the tides further upstream.
Tide tables tell you when it will happen, based upon the lunar cycle, but they in no way account for the day-to-day effects of weather on the actual flow through a given estuary.
That's kind of the point... you would need a large number of huge grid scale hydrogen storage facilities. Nothing like that has ever been built anywhere, and although it's theoretically possible it will cost a huge amount and have many challenges to be solved - it may well be a good solution in the end, but you can't brush it aside as though it doesn't affect the case for 100% renewables. None of the countries which rely on nearly 100% renewable energy have done that because their sources aren't as variable as the sources we have available in the UK, so you can't use them as some kind of example that we could easily follow.
I guess you're arguing against nuclear by talking about damage making a whole region uninhabitable? That's kind of beside the point looking at reliability and environmental impact. However I'd disagree about 'damage' to a modern nuclear plant leading to a whole region being uninhabitable. If you're looking at 'worst case' planning rather than real risk there are plenty of risks associated with hydroelectric schemes going wrong, or huge hydrogen storage facilities catching fire...
The thing is 5% just doesn't solve any of the problems with going 100% renewable. It probably will complement other sources of renewable power, but you're still left with massive energy storage needs to ensure stability. Remember if we transfer things like heating and transport energy demands to electricity too then that 5% will become more like 1-2%... Also, there will only be a very limited number of places where conditions for tidal power are as favourable as the Severn estuary, so unless it can be done so cheaply that it becomes obviously competitive with other forms of unreliable and intermittent power like wind turbines even when built in less than ideal locations I'm not sure its prospects are that good for growing much beyond that.
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There is also the issue with the matter of scale. Both of manufacture and deployment.
Wind Turbines have now (for the most part) been designed in such a way as to be almost "universal" in their design and as such can be deployed in multiple locations with zero redesign or remanufacture.
If the strongest tidal estuary we have can only deliver 5%, then any other estuary we deploy that equipment to is only going to be worse, or have to be redesigned either in part or full for each given application. Bespoke engineering is both expensive and time consuming.
Because it has happened.Oh you're one of those people
I would like to see some numbers for that... nuclear power is essentially one of the safest forms of power in existence. Even if it were marginally true, it has many advantages in how compact it is and how stable the power production is.
You should stop driving a car. I heard a crash happened once.
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Indeed, for energy density it simply cannot be beaten. You can make so much power from a relatively small area of land - and considering how small the UK is compared to many other nations (France, Spain etc..) You'd think we'd be all over that.
*Edit* I mean when you think about it, it's kinda crazy we don't have way more reactors.. We have a complete coastline - even with areas that are the most inhospitable where NOBODY lives. Were geologically stable, so no real risks of any tremors / earthquakes / landslides.
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Is it safer compared to solar/wind/tidal? I doubt it
I stopped as I found a better alternative. Why take the risk when you can avoid it?
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Congratulations that worked for you, does not mean it works for everyone else.
Doesn't have to. Nothing always works for everyone
Soldato
- Joined
- 13 May 2003
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- 8,955
I attended an IMechE lecture on tidal power about 10 years ago and the expert engineers view who had been on the Severn Barrage scheme was that you could unquestionably achieve 7GW of continuous output in the UK from tidal power. Basically between the Severn, Mersey, Clyde, Firth, Humber, Wash and Thames you have a pretty much constant ebb of flow. But the environmental impact is the big issue whilst wildlife upstream of the barrage would increase in an absolute sense you would lose a large amount of tidal wetland that is essential to large numbers of bird speakers.
Caporegime
- Joined
- 22 Oct 2002
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- Boston, Lincolnshire
better to lose a few birds than go into climate change oblivion. Greater good and all that.