Nuclear is not intermittent and can maintain very stable turbine rotation though, which is great if you want to have a stable grid.
Wind energy requires either a very stable high-power backup (not only due to intermittency, but also variable output frequency), or losses to AC-DC-AC conversion and issues associated with inverters and sensitive motor-based devices.
Solar is intermittent and needs inverters, too.
So, all have their place. Some solutions do emerge, like pumped hydro storage, which both buffers intermittency and allows to directly obtain AC power with desired characteristics, but they’re not universally applicable and can fail through long no-power streaks.
Main issue is that voltage transformation in DC comes with massive losses, and so does power transfer at 100-200V.
AC allows you to easily and efficiently scale voltage up and down. Transmission lines are typically at 10.000-500.000V, allowing them to move massive amounts of energy with low amperage. As energy losses are dictated by amperage, keeping it low means your grid is very efficient.
Also, while there’s a growing requirement for various kinds of AC to DC converters to charge various batteries and use electronic devices, switching grid to DC will come with a giant reverse problem, as everything with a motor would need to convert from DC to AC. There are plenty of electric motors out there, some of them very sensitive to the imperfect output of most converters.
So, yeah, as much as I love the simplicity and low-scale efficiency of DC, it just won’t work too well when scaled.
Nuclear is not intermittent and can maintain very stable turbine rotation though, which is great if you want to have a stable grid.
Wind energy requires either a very stable high-power backup (not only due to intermittency, but also variable output frequency), or losses to AC-DC-AC conversion and issues associated with inverters and sensitive motor-based devices.
Solar is intermittent and needs inverters, too.
So, all have their place. Some solutions do emerge, like pumped hydro storage, which both buffers intermittency and allows to directly obtain AC power with desired characteristics, but they’re not universally applicable and can fail through long no-power streaks.
What about building DC nets, then?
Totally not viable for a grid-scale installation.
Main issue is that voltage transformation in DC comes with massive losses, and so does power transfer at 100-200V.
AC allows you to easily and efficiently scale voltage up and down. Transmission lines are typically at 10.000-500.000V, allowing them to move massive amounts of energy with low amperage. As energy losses are dictated by amperage, keeping it low means your grid is very efficient.
Also, while there’s a growing requirement for various kinds of AC to DC converters to charge various batteries and use electronic devices, switching grid to DC will come with a giant reverse problem, as everything with a motor would need to convert from DC to AC. There are plenty of electric motors out there, some of them very sensitive to the imperfect output of most converters.
So, yeah, as much as I love the simplicity and low-scale efficiency of DC, it just won’t work too well when scaled.