Maggie's Farm

Read about the weeks long power outage in Broken Hill Australia in November 24.

Population @30,000, typical peak electrical demand @36MW, typical average demand @25MW.

They have a 53MW (nominal) solar farm and a 200MW (Nominal) wind farm. Also many individual houses have solar panels.

They also have a 50, 75 or 100MWH battery (reports differ) which should power the town for 4-5 hours before it needs recharging.

A windstorm blew down transmission lines connecting the town to the power grid.

None of the solar, wind or battery could be used without being connected to the grid.

So with, nominally, 5-10 times the generating capacity they needed for the town, 30m people sat in the dark for weeks.

Whenever I talk about wind and solar capacity, I always include "Nominal". Most articles are misleading because they talk about a 2MW windmill or solar fieldas if it has the same capacity as a 2MW diesel or other ICE.

The 2MW diesel will run continuously and reliably at 2MW output for weeks or months at a time. It can be shut down, run full power or throttled as needed. "Dispatchable" as it is called.

So when you say 2MW capacity, it really means 2MW.

A 2MW (nominal) windmill or solar will generate 2MW when conditions are just right. But on average, they generate about 20-25% of the nominal rating. How much they generate also varies depending on the vagaries of wind and clouds.

So saying a windmill is 2MW, just as one might say a diesel is 2MW is not just disingenuous, it is a lie.

And then there is the whole issue of the type of power generated, fluctuating DC inverted to AC. This is not the same as power from a rotating generator. It is similar but it requires all sorts of electrical gymnastics to integrate the 2.

As as we learn from Broken Hill, Spain and other outages, if you do not have substantial rotating base generation, your renewables are so much junk.