Comment by jillesvangurp
6 days ago
Base load is one of those terms that nuclear power proponents love because it turns a negative in a positive. Nuclear plants are very expensive to turn off and on. Nuclear plants leave you no choice but to leave them running 24x7, even when power that is an order of magnitude cheaper is available most of the time. Proponents call this base load. But technically it's just very expensive power that you can't turn off when it's completely redundant.
Flexible load is where the action is these days because renewables sometimes push energy prices into the negative whenever there's too much of it. Having to expend fuel during such times is a negative thing.
The big benefit gas plants have over coal and nuclear plants is that you can turn them off and on quicker. So you don't have to run them 24x7. Newer coal plants are similarly cheaper to use for backup power generation. A common mistake with assumptions about Chinese coal plants is that yes they build lots of them. And no, they mostly aren't running a lot. Their coal use actually is starting to decline. The new plants are more flexible and they use them to replace the older ones.
Renewables are plenty and cheaper most of the time. Batteries can deal with short term fluctuations and help time shift renewable power to cover peak loads in the morning and evenings.
And if you can bring online some gas/coal power when it's actually needed, there is no need for base load.
In practice this is still quite often but not most of the time and gradually declining. With dirt cheap renewables + batteries coming online by the hundreds of gw per year, the ability to turn the rest off is the most important feature with backup power generation.
Nuclear plants remain stupidly expensive and lack this feature.
Civilian nuclear plants can be easily regulated between 50% - 100% of maximal output, with power gradients of up to 2% / min. (Submarine nuclear reactors are designed for even faster gradients). In France, because nuclear power plants are the dominating source of electricity, nuclear power plants have to ramp up and down the output on daily basis.
https://snetp.eu/wp-content/uploads/2020/05/SNETP-Factsheet-...
When possible you want to run nuclear power plant at 100%, because there are almost no savings in operating costs (because nuclear fuel is so cheap) in comparison to a nuclear power plant running at 50%.
The current Chinese electricity strategy is to minimize the costs of electricity, get as much electricity from hydro, wind, solar as cheaply possible and fill the rest with cheap coal power. China currently doesn't use batteries for renewables backup in any significant amount (in comparison the size of the Chinese electricity grid).
China currently doesn't have access to cheap natural gas, in contrast to US. The amount of electricity produced from natural gas is very small in China.
https://ourworldindata.org/profile/energy/china
Nuclear power in China is still very small, in comparison with coal power.
Will China build more and more renewables? Yes, but only if the costs of the whole electricity mix will stay low. They will not overbuild renewables. They will not build very large amounts of battery storage, if coal power will be cheaper.
China's coal use alone is more than all energy sources in the USA combined. Something like 70% of all energy, then oil, then about 10% renewable. USA is also near 90% fossil fuel but morally natural gas and oil, coal on the way out while China still opening gigawatts of plants yearly.
"Base load is one of those terms that nuclear power proponents love because it turns a negative in a positive."
I love how anti-nuclear types argue against such a basic concept as base load just because it helps THEIR argument. Base load is simply the lowest wattage the grid needs in a time period and does vary a lot but NEVER goes to zero. Wind and solar are a very poor fit for this due to their variability. Batteries can help but are expensive and wind and solar variability is offset using gas turbines.
Data centers always want to run 24/7 and significantly increase base load, which is why the big hyperscalers are all making deals for nuclear power. A nuclear reactor generating power for a data center that needs its entire output 100% of the time is an ideal scenario.
batteries are expensive? relative to what?
To natural gas turbines
> Nuclear plants remain stupidly expensive and lack this feature.
Combining nuclear with some secondary application that can run only at energy surplus times, such as desalination or pumped hydro, might help with the economics.
Desalination and pumping desalinated seawater through long distances might actually be a nice idea to reduce desertification or to increase agricultural output.
Nuclear powered desalination was demonstrated using BN-350 reactor.
https://en.wikipedia.org/wiki/BN-350_reactor
The question is always: costs. In the Middle East and North Africa dominating source of power for desalination is natural gas.
https://www.iea.org/data-and-statistics/charts/energy-consum...
Cost of the energy input is less important if it uses the energy surplus the grid isn’t paying for.
That would require an energy market with spot prices that incentivize the buildout.
this gets repeated over and over again but its false:
> Nuclear power plants are routinely used in load following mode on a large scale in France, although "it is generally accepted that this is not an ideal economic situation for nuclear stations".[42] Unit A at the now decommissioned German Biblis Nuclear Power Plant was designed to modulate its output 15% per minute between 40% and 100% of its nominal power.
from https://en.wikipedia.org/wiki/Nuclear_power_plant#Flexibilit...