Sustainable Power Isn't working

Science & Environment Science & Environment: Chat / Discussions
41

I completely agree. We have been building our own nuclear reactors (and associated systems utilising their power output) for our submarines for many years now. It cannot be an enormous leap forward to utlilise the same units for local power generation.

How many? Well, I have heard it claimed that one nuclear powered submarine could provide enough electrical power sufficient for a large town or city. Obviously, this would require quite a few to be build around the country, although it is possible that the basic design could be expanded to an extent sufficient to cover a wider area. Being a well established design, it shouldn’t take a great length of time to produce these power stations and get them into full working order. Probably not helped by our traditional dawdling by politicians and civil servants, of course.

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42

Yes I was disappointed that the first part of his argument was about the death of birds, very weak, but the bloke is a tree hugger and we should make allowances. I almost stopped watching at that point, but he did go on to make some very valid (to me anyway) points about unreliability. The USA is very large and frequently has different weather systems acting on different states, so it would be just a case of diverting energy production from a windy or sunny state, to a cloudy or windless one. No such benefit here in the UK butterscotch, when it’s cloudy, rainy, or windless, it’s usually nation wide.

There is a light at the end of the tunnel for sustainable power generation however, there is work progressing on what are called ‘Gravity Batteries’ in times of peak energy production from solar and wind, it is being used to lift heavy weights to extreme heights. At peak times of demand, the weights are then slowly released to turn alternators and turn the energy back to electrical energy for consumption. Very similar to the hydro electric plants where water is pumped to the top of a hill to be released when demand is greatest.

However, it makes the whole idea of sustained energy production and storage very expensive so I can’t see it catching on, especially when one nuclear power station will probably out produce these methods by at least hundred to one.

43

Why?
We have been making our own nuclear power systems in our submarines for years.
Why do we need foreign-made units?
I understand that it is Rolls-Royce who have come up with these SMRs anyway and, although I think RR is now owned by some foreign company(?), I believe that we have the technology here.
Or is it our glorious leaders who think they can make some sort of saving by farming out the work to foreign countries - like they do?

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44

Of course, both are much warmer and sunnier countries than the UK.

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45

@Bruce , Thanks for explaining all that Brucy, but from what you say you
are describing conventional large generating systems which drive
large heavy rotors, for instance, the rotor of one generator at the French
built atomic power station outside Cape Town SA weighed almost
300;tons, this took about 3 days to spin up after bring shut down for
fueling and maintenance !
Now the generators l am talking about can be fitted in a submarine , so
obviously are much smaller, why can’t multiples of these be used ?to power
the grid? Or even be used locally and do away with the grid alltogether ??
The required flexibility could be achieved by keeping some running and
some on standby and some being serviced at any one time ??After all, if
Thousands of solar cells can be connected to an existing system then it
should be simple to connect multiple generators as l have just described ??
Can you explain what the snags would be if it was decided to follow this route?
Donkeyman! :+1::+1:

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46

Tidal is an option Swimmy, but I think there is a long way to go yet before we can dismantle all our coal and gas power stations. There were very few occasions last year that we could supply our demands of electricity from ‘Sustained’ means only, and we are going to need a hundred times more wind turbines and solar panels to even come close. Imagine the amount of land that is going to take up. We moan now about the number of new houses being built. Are we destroying the environment we are trying to save? A Nuclear power station hardly takes up any land and produces the same output as 300 wind turbines at least.

47

Perhaps not Bruce, but he makes some very valid points that people like me (who are also not qualified) to comment on and perhaps learn something from the people who are. Where would we be in the world if people didn’t ask questions?

48

The units in submarines can power up very quickly, when needed. If the same concept is to be used in SMRs, then that should also be the case.

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49

Not quite sure what you mean


50

Good point Donkeyman
 :+1:
Although I’m not an authority on nuclear subs, I’m sure they can fire up their reactors in less than half a day and face the enemy. So if they can do it, why not use the same technology for generating electricity?

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51

I’m not sure that there is as much waste from a nuclear reactor as you think there is Mr Fraggle. :017:
I agree mostly about it been radio active for lots of years, but the amount of exposure depends on how long it will remain radio active. Some of the rods and surrounding areas will be contaminated for hundreds of years, but most of the waste will not.

52

Renewables met 97% of Scotland’s electricity demand in 2020strong text

53

Scotland is mostly mountains and Lochs Besoeker?

54

@Bruce ,Regarding SA Brucy, they have been experiencing rolling blackouts
for decades now, they even have to stop the mines operating at times
The reason for the high % of renewables there is due to the very low %
of low base load production caused by mis management and poor
workmanship in building coal fired power stations!
Politics also plays a big part in this !!
Donkeyman! :thinking::thinking:

55

What is nuclear waste and what do we do with it? - World Nuclear Association.

Quote:-
The generation of electricity from a typical 1,000-megawatt nuclear power station, which would supply the needs of more than a million people, produces only three cubic metres of vitrified high-level waste per year, if the used fuel is recycled. In comparison, a 1,000-megawatt coal-fired power station produces approximately 300,000 tonnes of ash and more than 6 million tonnes of carbon dioxide, every year.

56

@OldGreyFox BUT, the coal ash can make 20 zillion building blocks which
can be used to build 5million houses which will cover 5million acres
of greenfields !!
What a complicated web we’ve wove ??
Donkeyman!

57

Yes Donkeyman, every cloud

:sunglasses:

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58

A mixture but the renewable energy is mostly from The North Sea which doesn’t have mountains


59

The reason it takes so long is not the time it takes to spin it up you could do that in a few minutes were it not for other matters that have to be taken into account.

The boilers take a long time to heat up because of factors including, for example, that the superheater tubes would melt if done quickly (no steam, no cooling) and you also have to take into account the thermal expansion of things lke the drum of water which would be many inches thick yet only the bottom half is being heated and therefore expanding before any steam is produced. One of the restrictions on firing rate is keeping the top and bottom of this drum within a certain temperature of each other.

The same applies to the the turbine shaft, it is relatively light so heats very quickly but the casing is heavy , much thicker and takes longer to heat up. imagine the problems caused by the shaft suddenly becoming a foot longer than the casing.

It is not the spinning that takes time it is ensuring that all the parts expand together that takes the time.

I don’t know much about nuclear power plants but submarine nuclear power plants produce about 50MW each according to something I read about the French submarines. The units I worked on at Pyrmont Power Station (built in the 1950s) were air cooled 50MW sets which still took several hours to fire up each morning even though they had only been shut down less than 8 hours previously.

Just for your information steam powered turbo alternators produce AC power so require synchronising to the mains frequency by varying their speed (usually about 3000rpm on 50hz systems) whereas solar panels are DC and use inverters to connect to the mains these sync automatically to their output.

Assman, blackouts are caused purely by supply not meeting demand, it has nothing to do with renewables or base load merely insufficient investment in infrastructure. As you say this is a political thing not a failure of technology.

60

Hi

Back to the fray.

SMRs, small modular reactors.

They are not as small as you think, each one is the size of two football pitches, with the necessary ancillary buildings and parking etc, that moves up to 10 football pitches.

Small refers to their generating capacity, about a 25th of the new Nuclear Stations we are building.

They each generate about the same amount of electricity as 150 land wind turbines.

The advertising says they will each power around a million homes.

They will, providing the homes are well insulated.

What they will not power is the other bits and pieces we rely on, like sewage, industries, shops and traffic lights etc.

They are not similar to submarine nuclear power units, these generate a 10th of the power of a SMR and only work if they are surrounded by vast amounts of water.

SMRs also need lots of water for cooling, there is not going to be one in every town.

They also have costs to connect to the national grid.

They are also a security issue.

Our existing nuclear power stations are built to withstand serious attacks and a plane crashing into them.

SMRs are not, they are built in a factory, transportable by road and slotted together on site.

We have a small number of Nuclear Power Stations at the moment, one recycling plant and a limited number of transport movements of radioactive material.

These are protected by the British Nuclear Police.

These people are armed, they have very different rules of engagement, very different to those of Armed Police Officers and the Military.

Their job is to protect nuclear sites and materials during transport from attack.

They have instructions and permission to shoot to kill, no need to refer to a senior officer, an on the spot decision.

With the new announced Nuclear Power Stations the 1600 existing staff are going up to 5000, they will need an awful lot more if we go down the SMR route.

We will also need to protect them against Arial attack.

Possible, but expensive.

Having hammered SMRs, I think they are the way forward provided we build and operate them ourselves.