The Remarkable Progress of Renewable Energy

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Continuous Swing Adsorption Reactor (CSAR)

New technology makes carbon capture easier - SINTEF

A recent innovation has the potential to accelerate the introduction of essential carbon capture processes in a range of industries. The technology has recently been demonstrated at a waste combustion plant in Bergen, with excellent results.

www.sintef.no

 

[ZiprHead]

By installing several gigawatt-hours of battery capacity.

...which requires several giga-tonnes of carbon dioxide emissions to manufacture, and which extends solar electricity availability "into the evening", which is not quite "until the next morning".

Not an attack, just a question.

How many giga-tons of carbon dioxide emissions to build a nuclear power plant?

 

[bilby]

By installing several gigawatt-hours of battery capacity.

...which requires several giga-tonnes of carbon dioxide emissions to manufacture, and which extends solar electricity availability "into the evening", which is not quite "until the next morning".

Not an attack, just a question.

How many giga-tons of carbon dioxide emissions to build a nuclear power plant?

According to this paper:

The results show that the total emissions resulting from vegetation loss, equipment manufacturing and labor input during construction and operation are 1232.91 Gg CO2 with a carbon intensity of 1.31 g CO2/kWh
...
The average carbon emissions at the front end, construction and operation and the back end were 11.45, 7.82 and 3.07 g CO2/kWh, respectively.

1232.91 Giga-grams (Gg) is 0.00123291 Giga-Tonnes; If that's equivalent to 1.31g.CO₂/kWh, and construction of the plant contributes 11.45g.CO₂/kWh, then that gives a construction emissions total of about 0.0107 Giga-Tonnes.

The important measure for comparing power systems is the g.CO₂/kWh. How much carbon dioxide is produced per unit of energy supplied to end users? For the Nuclear plant in the study quoted above, that figure is 11.45+7.82+3.07=22.34g.CO₂/kWh.

This figure must, to be useful, include all emmissions, from the whole system; If you are looking at Solar power, for example, you need to include emissions from panel manufacturing and eventual disposal; From transporting the panels from factory to installation site; From manufacturing of any inverters and transformers required; And from whatever system you use to obtain power when it is needed but the sun isn't shining - in this case, the batteries.

It's that last one that often gets ignored (and it applies to any generation technology - even nuclear plants don't have a 100% availability, so we must include emissions from whatever we use to generate electricity when the plant is not running; But it's generally only significant for intermittent generation, ie Wind and Solar); In my home state, the last one is coal fired power plants, which make the system emissions FAR higher than the solar advicates want to admit. Batteries might be less awful, but that's very difficult to determine, not least because batteries practically don't exist at the scale of national power grids - they are an utterly minuscule contributor to generation balancing, almost all of which is still done by pumped-storage Hydro.

A hundred nuclear plants produce about a Giga-Tonne of carbon dioxide in their construction; But it makes in the order of a million kWh (1GWh) for every hour of operation, and can operate for sixty years at 90-95% availability. A million kWh of battery storage is an astonishingly large amount of batteries; And they will need replacing several times in sixty years.

Lithium ion batteries generate about 2 tonnes of CO₂ per kWh in their manufacture; A gigatonne of carbon dioxide would "buy" you about 500GWh of storage (you still need generation!), and maybe last ten years; 100 nuclear plants get you about 500GWh of electricity every five hours for sixty years, from the same tonnage of emissions.

At the end of the day (or more importantly, the year), all that matters is the total systemwide g.CO₂/kWh. We need to cut that, sharply and rapidly.

Here's Europe in 2023:



We need to all do what the countries mostly showing in green (like Sweden, Norway and France) are doing, and to avoid doing what the countries mostly showing in brown (like Poland, Germany, and Italy) are doing.

Based on the goal of reducing carbon emissions overall and system wide, two conclusions are obvious:

What we need to do more of is Hydro, Geothermal, and Nuclear.

What we need to do less of is Coal, Gas, and Intermittent Renewables.

But that's only if we care more about actual outcomes, and not so much about feeling as though we are "in touch with nature".

 

[ZiprHead]

Thanks, Bilby.

 

[Loren Pechtel]

A hundred nuclear plants produce about a Giga-Tonne of carbon dioxide in their construction; But it makes in the order of a million kWh (1GWh) for every hour of operation, and can operate for sixty years at 90-95% availability. A million kWh of battery storage is an astonishingly large amount of batteries; And they will need replacing several times in sixty years.

That high????

What we need to do more of is Hydro, Geothermal, and Nuclear.

Hydro has the effect of messing up the river ecology. It's nowhere near as benign as people think.

 

[bilby]

A hundred nuclear plants produce about a Giga-Tonne of carbon dioxide in their construction; But it makes in the order of a million kWh (1GWh) for every hour of operation, and can operate for sixty years at 90-95% availability. A million kWh of battery storage is an astonishingly large amount of batteries; And they will need replacing several times in sixty years.

That high????

For a hundred plants? Sure. There's a lot of concrete in 100 nuclear power plants.

What we need to do more of is Hydro, Geothermal, and Nuclear.

Hydro has the effect of messing up the river ecology. It's nowhere near as benign as people think.

Indeed; And the number of suitable sites not already in use is small. But I am only talking about catbon dioxide emissions, and am ignoring other environmental issues.

Nuclear is excellent on those, because of its relatively tiny land-use footprint.

 

[Loren Pechtel]

A hundred nuclear plants produce about a Giga-Tonne of carbon dioxide in their construction; But it makes in the order of a million kWh (1GWh) for every hour of operation, and can operate for sixty years at 90-95% availability. A million kWh of battery storage is an astonishingly large amount of batteries; And they will need replacing several times in sixty years.

That high????

For a hundred plants? Sure. There's a lot of concrete in 100 nuclear power plants.

What I was questioning was the up time. Unless they build a reactor that can do fuel changes while in operation I can't see that kind of uptime. AFIAK nobody has built such a reactor. I see how one could be made, though: Adjoining the reactor you build an airlock big enough that fuel rods can be pulled from the reactor to the airlock. Flood the airlock, the rods to be changed out are pulled into the airlock, the hatches closed and the coolant pumped out. Extract the rods, replace them with fresh rods. Flood, insert the new rods and pull out others. The system can be slow, it only needs to be able to cycle fast enough to change out all the rods in whatever interval the reactor requires. Everything has to be robotic anyway, the difference in this case is that the robotics need to be able to operate while bathed in whatever the reactor uses in it's primary loop.

 

[bilby]

A hundred nuclear plants produce about a Giga-Tonne of carbon dioxide in their construction; But it makes in the order of a million kWh (1GWh) for every hour of operation, and can operate for sixty years at 90-95% availability. A million kWh of battery storage is an astonishingly large amount of batteries; And they will need replacing several times in sixty years.

That high????

For a hundred plants? Sure. There's a lot of concrete in 100 nuclear power plants.

What I was questioning was the up time. Unless they build a reactor that can do fuel changes while in operation I can't see that kind of uptime. AFIAK nobody has built such a reactor. I see how one could be made, though: Adjoining the reactor you build an airlock big enough that fuel rods can be pulled from the reactor to the airlock. Flood the airlock, the rods to be changed out are pulled into the airlock, the hatches closed and the coolant pumped out. Extract the rods, replace them with fresh rods. Flood, insert the new rods and pull out others. The system can be slow, it only needs to be able to cycle fast enough to change out all the rods in whatever interval the reactor requires. Everything has to be robotic anyway, the difference in this case is that the robotics need to be able to operate while bathed in whatever the reactor uses in it's primary loop.

The average capacity factor for existing nuclear power plants in the US is around 92%. (2021 data from: https://www.energy.gov/ne/articles/what-generation-capacity). Over the longer run from 2006-2012, US nuclear plants averaged 88.7% capacity factor. There have been continuous improvements in fuelling times and reductions in maintenance shutdowns between 2012 and the present; Plant owners have a significant financial incentive to reduce the shutdown times as far as possible.

Many plants routinely exceed 100% of their rated summer capacity, due to the larger temperature gradient available in cold weather leading to electricity output above the nameplate power rating of the facility.

The Kaiga Nuclear Plant in India holds the world record of 962 days of continuous operation between shutdowns.

When your reactor only needs fuelling every two years, you can get a 99% capacity factor even if fuelling requires a whole week - and with sensible planning, a week is a very long time, for pulling a few fuel bundles out and putting new ones in their place.

Capacity factors of 90-95% are now routine in the nuclear industry.

 

[Tharmas]

The right-wing governor of the state of Texas, Greg Abbott, announced yesterday that he intends to introduce a bill to the legislature creating a state atomic commission, with the goal of making Texas the leader in U.S. atomic power.

 

[bilby]

The right-wing governor of the state of Texas, Greg Abbott, announced yesterday that he intends to introduce a bill to the legislature creating a state atomic commission, with the goal of making Texas the leader in U.S. atomic power.

Yeah, the thing the nuclear power industry is crying out for is more government regulation and interference.

Or is this a precursor to Texan seccession from the Union, taking their nuclear industry out of the jurisdiction of the NRC? I gan see lots of positives there, not least that Texas provides the GOP with a big chunk of their power in both Federal executive and legislature. But I doubt that any Republicans would agree that these would be positives.

 

[Jimmy Higgins]

The right-wing governor of the state of Texas, Greg Abbott, announced yesterday that he intends to introduce a bill to the legislature creating a state atomic commission, with the goal of making Texas the leader in U.S. atomic power.

Odd... I thought becoming a leader in atomic power would imply building out nuclear power plants and getting lots of your energy, to most of your energy from nuclear power.

I suppose this is better than him announcing fourteen new coal power plants. Until we find out the head of the Commission runs Massey Coal.

Of course, the other issue is what good is being a leader of atomic power, if you are cut off from the remainder of the US power grid?

 

[Loren Pechtel]

The right-wing governor of the state of Texas, Greg Abbott, announced yesterday that he intends to introduce a bill to the legislature creating a state atomic commission, with the goal of making Texas the leader in U.S. atomic power.

The reactors need to be in blue states.