Is nuclear power really green?

[saveasteading]

I know it makes radiation and is dangerous but I've just twigged something. Boffins comments sought.

 

 

Wind, sun and water all provide a fairly closed loop of extracting energy from current nature and releasing it as heat almost in real time. Effect on the planet fairly small.(?)

 

But can a boffin confirm that nuclear does not have this benefit?

 

Oil coal and gas are energy stored over millions of years , being released over tens. Bad.

 

Burning timber from commercial forests is the sun's resources collected over a few decades.

 

But Nuclear energy was created in the Big Bang, quite a whike ago, so is adding to heat gain in a sudden manner and is not "renewable". Bad.

 

 

 

So we should only use sun, wind, hydro and tides, but perhaps some timber from waste, and from rubbish.

[-rick-]

12 minutes ago, saveasteading said:

But Nuclear energy was created in the Big Bang, quite a whike ago, so is adding to heat gain in a sudden manner and is not "renewable". Bad.

 

Firstly, I think we are talking about renewable in the sense of 'planet earth has limited supplies'. Once we go off planet the resources available are vast (but the technology required to access them are also a long way off).

 

If we are just worried about planet earth then the available resources for nuclear is more than enough to keep us going for a very long time without worrying about depletion. If nuclear was cheap and we had well developed end-of-life plans I don't see much issue with it given current safety standards. But it's not cheap and we don't have well developed end of life plans so I'm not a huge fan based on that. Having said that, if the safety aspect can be dealt with putting small nuclear on very big ships would eliminate a lot of emissions and potentially lower costs for everyone.

 

Using nuclear generation produces heat and some have questioned whether that heat output is a negative given global warming. My understanding is that the amount of energy used/heat produced by human activity is absolutely tiny compared to the amount of heat/energy output into planet earth from the sun and it's therefore not remotely a concern. Maybe a concern in local areas (heating seawater locally, producing fog in local valleys, etc). But these are the same as any other steam using power source (gas, coal, wood, etc).

[jack]

8 minutes ago, -rick- said:

Using nuclear generation produces heat and some have questioned whether that heat output is a negative given global warming. My understanding is that the amount of energy used/heat produced by human activity is absolutely tiny compared to the amount of heat/energy output into planet earth from the sun and it's therefore not remotely a concern. Maybe a concern in local areas (heating seawater locally, producing fog in local valleys, etc). But these are the same as any other steam using power source (gas, coal, wood, etc).

 

100% agree.

[saveasteading]

30 minutes ago, -rick- said:

renewable in the sense of 'planet earth has limited supplies'.

I'm not really . I'm being perhaps being lazy and vague. I mean readily renewable, not laid down millions of years ago.

 

32 minutes ago, -rick- said:

not remotely a concern.

Not my understanding. Unless the climate change is all down to pollution rather than energy release.

 

Small nuclear sounds worrying. If VW, Dacia (and some others) start putting it in cars we have to worry a lot about the quality control and back-lot mechanics. (Easier to express for cars than with ships)

[LnP]

2 minutes ago, saveasteading said:

 

Not my understanding. Unless the climate change is all down to pollution rather than energy release.

 

Climate change is due to the changing chemical composition of the atmosphere, which causes heat from the sun to be trapped and the planet to heat up. It's not due to the heat which is released from human activity.

[JohnMo]

35 minutes ago, -rick- said:

we don't have well developed end of life plans so I'm not a huge fan

Not sure there are any long term plans except concrete and lead lining of fuel waste, components removed during the plant life treated in a similar manner. Then decommissioning taken several lifetimes.

 

Impact on the planet ignoring the above is pretty small, you use the heat to make steam that drives a steam turbine or two. There is no combustion by product that leads to global warming - just super heated water, used in the turbines.

 

Renewable - no, radiation is from a fuel source it gets depleted and converted to a waste product. It happens the waste product is very dangerous to all life.

[JohnMo]

6 minutes ago, saveasteading said:

Small nuclear sounds worrying. If VW, Dacia (and some others) start putting it in cars

It's not that small as you need a steam plant to go with it. So would be a car a 10 Tonne trailer.

[-rick-]

3 minutes ago, saveasteading said:

Not my understanding. Unless the climate change is all down to pollution rather than energy release.

 

Solar is 1000W/m2. Work out how many m2 of the planet there is and calculate the total amount of energy (obv not all planet is exposed to sun at same times). I'm sure an AI will help do this.

 

Then calulate the amount of energy we put out. It's a very very tiny fraction of total energy.

 

3 minutes ago, saveasteading said:

Small nuclear sounds worrying. If VW, Dacia (and some others) start putting it in cars we have to worry a lot about the quality control and back-lot mechanics. (Easier to express for cars than with ships)

 

Haha here comes the jetsons!

 

No, not gonna be in cars any time soon (or trucks). Batteries are perfectly fine for those. Ships, and only very big ships, there are are really two options to power them that don't burn vast quantities of fuel.

 

1. Sail

2. Nuclear

 

Some ships are trying out sail and modern systems are aimed at reducing fuel burn not eliminating it. A useful contribution but not game changing. Ships have a schedule to keep so can't be waiting around for the right wind conditions. Nuclear on those ships is not crazy. They already have largeish crews with dedicated specialist engineers on board. The type of nuclear talked about for those ships is the 60-100MW range, so tiny comparitively. Likely to be an inherently safe design that is packaged as a module and craned on/off for maintenance, etc.

[SteamyTea]

Shame I am work at the moment.

When I studied RE we looked at all firms of electricity production. Nuclear, when generating is very low CO₂ generation. The long term storage is a problem, mainly political, latest idea is to bury it in the Irish Sea mudstone. It may happen.

There is a question mark over the security of uranium supplies, processing, transport and storage.

 

Regarding the excess thermal energy heating the atmosphere, not really. But local heating is a problem, as is excess air temperature. A French reactor was on reduced power because it could not get enough cooling. All large thermal plants cab suffer from that.

 

The main thing is to reduce the CO_2e gasses and particulates. These are the main problems.

CO_2e gasses do not act like a blanket, depending on which model used to calculate, it really just allows more energy to be stored kinetically (temperature is the mean free path speed of molecules after all).