Orkneys is a tiny (20k) region, that is connected to the national grid. That's how they solve their intermittency. That they produce excess energy during peak, is fine and dandy, but that's not what we're trying to solve here.
>Add whatever pumped storage and battery the grid might require.
Woah woah woah woah. You just yadda-yadda over the MOST important part. You know, the thing that makes solar/wind unworkable. Pumped storage requires very specific geography and huge land-use. It is not a general purpose answer. And there is no battery technology to power a modern city (much less a nation) for even minutes, much less weeks.
Now what?
>I suspect it's only vested interests stopping us.
I specifically called out their being tiny. Which is why we need a larger scale example. Nevertheless, despite having the interconnect they are a nett exporter each year, and at the export capacity of that interconnect. Being tiny there is nowhere to put pumped storage, yet they are already using a smart grid managing household, and I think EV batteries. So yeah, they use the grid as storage.
Of course pumped storage, and other storage is a general purpose answer. You don't need 100% capacity to power a nation for weeks. Chances of no sun at all, no rain and empty rivers, and no wind across the whole British Isles, or Europe, including offshore? Nil. So now it needs an appropriate balance of sources, and storage. I don't know what that is in TWh, but I know with certainty it is not "running a nation for weeks".
In reasonable terms, some mix of new projects like Dinorwig, that can run for about 6 hours at max power, battery, managed battery and the more exotic like power to hydrogen - already in use in Orkney, and molten salt that can cover some period far less than weeks will be the right answer.
No, it really isn't. They are inseparable in building a smart grid of intermittent sources.
A house that is an overall exporter still needs coverage for the night time. Maybe household battery, maybe import from the grid. It does not need a battery capable of weeks or even an entire day.
A city needs some TWh capacity when solar is not functioning, some other capacity when wind is not functioning, etc. It's perfectly reasonable to import some of that from other parts of the country or region which aren't currently cloudy or wind-free, and export when there is excess. Storage needs to cover any shortfall, and some excess to cover growth and the unforeseen. It doesn't need to run for weeks assuming zero replacement for a period of dead calm, or assuming country or continent wide dead calm.
If you want every house or city a self contained island without grid interconnect, then your storage requirements ramp up markedly.
Sure, the covariance between solar and wind production at one site isn't 1; and the covariance between all the contributing sites for wind isn't 1. So it does smooth out to some extent. (To some extent-- there are practical limits on grid size).
However, it's inescapable that you need a whole lot of storage. As we conceptualize it now, the grid has to remain available during 1% and 0.1% events.
Again, your point is orthogonal to what was said. If someone grouses about storage, mentioning a net exporter provides zero information. Mentioning that my house is a net exporter does nothing to inform them.
Orkneys is a tiny (20k) region, that is connected to the national grid. That's how they solve their intermittency. That they produce excess energy during peak, is fine and dandy, but that's not what we're trying to solve here.
>Add whatever pumped storage and battery the grid might require.
Woah woah woah woah. You just yadda-yadda over the MOST important part. You know, the thing that makes solar/wind unworkable. Pumped storage requires very specific geography and huge land-use. It is not a general purpose answer. And there is no battery technology to power a modern city (much less a nation) for even minutes, much less weeks.
Now what?
>I suspect it's only vested interests stopping us.
No. It's not. It really isn't.